Cooling Tower Sizing Rule Of Thumb


Divide your answer by 12,000: 1,950,000 / 12,000 = 162. Potential Flight Hazards. Approach decides or govern the size of the cooling tower to be selected. This rule recommends degrading the tower performance by approximately 1% for every 10,000 ppm of salts in the feed water. A better way is to assess the length of the header and the acceptable pressure drop; and then use the Darcy-Weisbach or other commonly accepted formula. VersaCross ® Fill A good rule of thumb is that the installed cost of a replacement tower is between 2 and 2-1/2 times the cost of the tower alone. Building is underway now on the ITER scientific installation in Saint Paul-lez-Durance, France. Following are some rules of thumb that may be used in general gen set cooling system sizing exercises: For every 304. than the restaurant or bar area … read more. 0 - HVAC Refrigerants. Windage Loss from Cooling Towers (Water Lost from Friction Between Wind and the Surface of the Water in Cooling Towers): Commonly 0. , a full-line, full-service industry leader in the design and manufacture of evaporative cooling towers and air-cooled heat exchangers, announces the release of an informational video that describes the differences in size and capacity between three Marley® NC® cooling tower model platforms: the Marley NC8407. Cooling Water ∙ Reverse Osmosis ∙ Injection Wells Predicting Properties of Blended Waters Presented at the 2008 AWT Annual Convention & Exhibition : Cooling Water Water Treatment Rules of Thumb: Myths or Useful Tools Presented at the 2003 AWT Annual Convention & Exhibition. Substitute the following wording for the requirements in IECC section C403. Techniche TechKewl 6626 Phase Change Cooling Vest with Inserts and Cooler - Blue. Also, if you're interested in learning even more, here's a free download for you: Standardized EMCS Energy Savings Calculations (20. Obtain updated equipment load data matching the usage;. 575 South Glaspie Street Oxford, MI 48371 USA. First, the lower the compression ratio is, the lower the energy consumption. Cooling Tower Basic Calculations. Water-cooled chillers are available in a wide range of sizes— from 20 tons to several thousand tons of cooling capacity. For reference, BTU is simply a designation of cooling power – the higher the BTU the more powerful the cooling. ” EFFICIENT USE OF RESOURCES. 55 Tower fill is of a highly open structure so as to minimize pressure drop, which is in standard practice a maximum of 2 in. For ideal mixtures, relative volatility can be taken as the ratio of pure component vapor pressures. A common rule of thumb is that the design temperature should only be exceeded for 2-3%. Cooling tower calculation (1) (1) 1. Two liquid control valve sizing rules of thumb are 1. 1090 Northchase Pkwy SE. 2 ppm free chlorine residual but want 0. In order to select an appropriate cooling tower, some data points needs to be considered such as: Water flow rate, Temperature variation (Range) & Design wet bulb temperature. North Korea is set to blow up the cooling tower at its nuclear plant on Friday, a symbolic move to show its commitment to a disarmament deal a day after it handed over a long-delayed account of. This amount of heat could theoretically melt 1 ton of ice in 24. Considerable energy savings are available by letting tower water temperature drop, rather than artificially holding it above 75°F (23. The temperature on the hot side into the tower should be about 120 F. Passive Low Energy Cooling of Buildings: Baruch Givoni. 5 Btu/hour of cooling per square foot. xlsx), PDF File (. 2007 Cooling Tower Failure at Vermont Yankee The above pictures are just part of the incredible story which is the Vermont Yankee saga. Please contact Opti Temp for conditions such as LWT temperatures above or below rating point, 50Hz operation, high altitude, E. The rule-of-thumb design method provides information useful in power plant cycle optimization, including tower dimensions, water consumption rate, exit air temperature, power requirements and construction cost. }, abstractNote = {A survey of wet cooling tower literature was performed to develop a simplified method of cooling tower design and simulation for use in power plant cycle optimization. Take into account different variables. For this I'm estimating the unit to run 14 hours per day which is fairly typical for this size and type of store. All our motors have unique specifications thanks to joint development with our motor suppliers. Air Conditioning Calculations - Rule Of Thumb. 1-800-525-8173. DETERMINATION OF COOLING TOWER AVAILABILITY for Oyster Creek Generating Station Forked River, New Jersey FINAIL REPORT Prepared by: UlRS URS Corporation 335 Commerce Drive Suite 300 Ft. Resubmission shall be required of any disapproved permit. Approach decides or govern the size of the cooling tower to be selected. 1 Component over-sizing Over-sizing of cooling plant can mean that at least some of the following items are over • chillers and cooling towers • pumps, pipes and valves • plant rooms, risers, and ductwork. At Pelonis Technologies, we’re here to make your life easier. Includes 53 different calculations. Using fans in this way greatly reduces energy consumption, compared with air-conditioning. Cleaning the bulbs and glass in your grow room can help you maintain the maximum light output at all times. Accident Cause Factors. The equivalent ton on the cooling tower side actually rejects about 15000 Btu/h due to the heat-equivalent of the energy needed to drive the chiller's compressor. Sipe, Mechanical Systems Manager, GAI Consultants. The equipment heat load can be obtained by identifying the current requirements for each piece of. 2 Online disinfection means – Dose the cooling tower water system with either a different biocide or a similar biocide at an increased concentration than currently used. This space allocation does not include space requirements for common areas, closets, restrooms, etc. Sun, Wind and Light: Architectural Design Strategies, Third Edition. But to achieve effective water treatment in either of these settings, the precise system volume must be known. Calculating the Pump Head The most common open system is the cooling tower portion of a chilled water system, as significant pressure drop that would not be covered under the equivalent feet of piping rule of thumb. This amount of heat could theoretically melt 1 ton of ice in 24. 1) For a typical recirculating cooling tower water system, approximately 1% of the recirculating rate (R) of the cooling water is evaporated for every 5. Cooling Tower plays a major role in Chemical Process Industry. 's handy, superbly organized data bank follows the CSI MasterFormat. Approximately 1,000 BTU's are required to evaporate. The improper use of this rule can lead to errors of judgment when analyzing the results of changing conditions. Hamon aims at offering the best economical solution for the lifetime of field erected cooling towers. 2) Multiply the results by 0. This temperature differential is normally between 10 and 20 degrees F. 1kW=3412 BTU/Hr Tons = (BTU's / hr) / 12,000. info The dominance of steel in the multi-storey commercial sector is based on tangible client-related benefits including the ability to provide column free floor spans , efficient circulation space, integration of building services , and the influence of the site and local access conditions. They are only typical values, which SHOULD BE VERIFIED for each application. When sizing portable cooling equipment, the rule of thumb is to plan on 3. Washington, PA 19034 March 2, 2006 AMERGEN ENERGY COMPANY, LLC. Conversions. 00 per linear ft. A general rule of thumb accepted by 3D printer users suggest a line width up to 50% bigger than the nozzle. The equipment heat load can be obtained by identifying the current requirements for each piece of equipment and multiplying it by the operating voltage (for all single phase equipment). Phone: (405) 290-7788. Such items as pump design, suction piping design, suction and discharge pipe size and pipe supports must all be carefully considered. Some of the old "rules of thumb" such as five times recirculation rate just are not accurate enough for most applications. A Building Management System (BMS) is a system designed to control, monitor and optimise various building services, including lighting, heating, ventilation, cooling, swimming pool pumps and water use in cooling towers. For example, if a furnace requires a 3" supply, then a 4" return is used. A useful "rule of thumb" is that the vapor pressure of a substance roughly doubles for every increase in 10 °C. In order to establish the basis for comparison the following assumptions were made: 2,100 SF house; finished basement; first … Continue reading "TYPICAL HEATING. the utilization of smart breakers. For ideal mixtures, relative volatility is the ratio of vapor pressures a12 1⁄4 P2 =P1. When the flow is reduced or restricted, it can create undesirable laminar flow (less than 3 feet per second) through the chiller, which can also cause a water treatment program to fail. Power is available at 460Volts, 3 phase, 60Hz. CONDITION OF TEST: 1. Rules of thumb for control valve selection include: 21 • Assume the valve will dissipate, at the maximum controlled flow rate, 10% to 15% of the total pressure drop through the pipeline, or 70 kPa (10 psi), whichever is greater. As a result, plumes emitted by cooling towers, tilt more rapidly under the effect of wind, than those emitted by stacks. The water additives include sulfuric acid, Nalco. now do to new laws and new construction, load calcs are becoming a requirement in some states and localities. As a rule of thumb, the amount of oxygen brought in the pond is twice the power of the turbine. 1) For a typical recirculating cooling tower water system, approximately 1% of the recirculating rate (R) of the cooling water is evaporated for every 5. 8 o C is what manufacturer can guarantee. It's often in the neighborhood of 1 ton of air conditioning capacity for each 600 square feet of conditioned floor area, usually abbreviated 600 sf/ton. Second, their water pressure drops must be accounted for when sizing the circulating pumps. 20(A) and 215. I am an air conditioning contractor and I have something to confess when it comes to air conditioning equipment sizing: As a community, we don't measure. basin of the tower. Tower operating pressure is determined most often by the temperature of the available condensing medium, 100-120 F if cooling water; or by the maximum allowable reboiler temperature, 150 psig steam, 366 F. L (m3/hr) =0. Cooling towers are structures typically found on the roofs of large buildings that enclose large fans used for ventilation and cooling. This water is available from plant wells, municipal supplies, and, increasingly, treated municipal wastewater. All cooling tower discharges must be in accordance with applicable state, local or federal rules and regulations. Almost 1/4 th of makeup water (water added in a cycle to substitute water losses) in a cooling tower is dissipated [25]. The input objects CoolingTower:SingleSpeed and CoolingTower:TwoSpeed provide models for single-speed and two-speed cooling towers that are based on Merkel's theory (Merkel 1925), which is also the basis for the tower model included in ASHRAE's HVAC1 Toolkit for primary HVAC. Four fundamental factors affect tower size: heat load, range, approach, and ambient wet-bulb temperature. Now we will discuss how to evaluate the efficiency of the cooling tower in a simple and practical way. 7 x the cooling load. limit of 300 ppm in Regulation 8, Rule 2. An Evaluation of General "Rules of Thumb" in Amine Sweetening Unit Design and Operation Luke Addington and Chris Ness Bryan Research and Engineering, Inc. cooling tower chemicals shall be furnished with the notification. consumed) depends on the of the cooling tower and on the. What is a cooling tower? A: Under the Legionella regulation, the term "cooling tower" means a cooling tower, evaporative condenser or fluid cooler that is part of a recirculated water system incorporated into a building's cooling, industrial process, refrigeration or energy production system. Vortexing in a cooling tower occurs in the A. Very easy to calculate water evaporation loss, Here is an example. 2The Screener Survey was sent to a sample of the manufacturing facilities that may be impacted by the rule. The performance of the cooling tower depends on various parameters like Range & Approach. The NH-U14S DX-3647 features a larger, custom-designed contact surface and supports both square and narrow type LGA3647 platforms. Nor are the indicated guidelines intended to take the place of direct contact and discussion with a reputable cooling tower manufacturer. Approach decides or govern the size of the cooling tower to be selected. The scale and scope of the ITER Project rank it among the most ambitious science endeavors of our time. Cooling systems rely on evaporator coils through which refrigerant fluid changes from liquid to vapor, cooling the coils in the process. Algae: A low form of plant life which generally requires sunlight and air for existence. A cooling tower is like the outside unit for your air conditioning but instead of transferring energy via convection, it transfers energy via evaporation. Let say we have cooling tower with the following data: Inlet water flow rate = 10 000 gpm. Energy Efficiency. Air Conditioning and Heating Sizing - It is not uncommon for HVAC estimators or HVAC contractors to use various rudimentary techniques, which are generally referred to as rules of thumb. 3MB PDF) General Information Air Movement 6 ACH 1 CFM/ft2 Ventilation Rate 5 CFM/person Fan Energy 1000-1500 CFM/hp Electric Motors 0. A lot of times, your AC contractor would want to size your AC using the rule of thumb. This combined with the foulant in the cooling water make conditions worse with corrosion, scale, and microbiological fouling as a result. Substitute the following wording for the requirements in IECC section C403. CTI STD-201 (09), Standard for Certification of Water-Cooling Tower Thermal Performance : CTI Code ATC-105 (00), Acceptance Test Code for Water-Cooling Towers ATC acceptance test code. Most chilled water systems operate with about 60°F temperature difference between the condenser and the evaporator. Cooling towers are structures typically found on the roofs of large buildings that enclose large fans used for ventilation and cooling. This amount of heat could theoretically melt 1 ton of ice in 24. I ran 15 gallons last night in 2 1/2 hours and the cooling water never got over 113°. Mission EnduraCool Multi-Cool. EGG-GTH-5775 July 1981 "WET COOLING TOWERS: 'RULE-OF-THUMB' DESIGN AND SIMULATION" Stephen A. The extent of cooling tower performance, with the tower's basic function of water heat rejection to the atmosphere, has such vital importance in HVAC, commercial, industrial, and large power facilities. I know the theoretical limit is the dry bulb temperature which appears to be about 75 F during the summer. 1 Key Drivers of the Cost Model 13 3. Obtain updated equipment load data matching the usage;. 5%; 1°F decrease of condensing water temperature improves the chiller efficiency by approximately 1. Injection Moulding – The raw plastic material is taken from a hopper into the extruder and is heated and forced through a nozzle to inject the plastic into the closed mould. through the cooling towers used to cost the towers), and Flow Used for Costing Activities Other Than Cooling Tower (this is the volume of water through the intake structure used to cost intake technologies). Because cooling water is not required for traditional CTs, the rule-of-thumb is that CC plants require about a third of the water that ST plants require because of the general ratio of 2 CTs/1 ST. The material used to protect the sides must be durable and easily cleaned. 's handy, superbly organized data bank follows the CSI MasterFormat. That's what I wrote in my last article. Top Five Warehouse Cooling Problems and Solutions Warehouses are an important element of the modern economy. Optimising these services can result in energy savings. North Korea is set to blow up the cooling tower at its nuclear plant on Friday, a symbolic move to show its commitment to a disarmament deal a day after it handed over a long-delayed account of. Air Flow Drift. Cooling Water ∙ Reverse Osmosis ∙ Injection Wells Predicting Properties of Blended Waters Presented at the 2008 AWT Annual Convention & Exhibition : Cooling Water Water Treatment Rules of Thumb: Myths or Useful Tools Presented at the 2003 AWT Annual Convention & Exhibition. The Tower 900 Introduction Guide Buy Now. one quick ex. The manufacturing facility has a total of four process cooling systems sized for 250 to 300 tons each. Telford & Wrekin Council's Files and documents available for download within the following categories, Public Protection (Environmental Health, Licensing and Trading Standards), Licensing, More licences. The standard rule of thumb is that the recirculataion rate is three times the tonnage of the tower. air intake of a cooling tower, enclosures utilized to hide the tower from public view are of primary concern and will be the subject of the remainder of this paper. 575 South Glaspie Street Oxford, MI 48371 USA. 47 tab gets a $12 tip. The purpose of a cooling tower is to conserve water. Chapter 3 reviews some basics on chillers, cooling towers, pumps, and other plant equipment. Calculating the cooling capacity needed for your room is a complicated process as there are many factors to consider. humidification) or removed (by cooling or dehumidification). Considering. I made a home made cooling tower to cool the water as it returns to the bucket. Our typical rule of thumb for the expense in repair or the full unit replacement is 70% of the cost of a new unit. 575 South Glaspie Street Oxford, MI 48371 USA. Commercial Cooling A more densely populated, cross-ventilated area requires about one ton of cooling (12,000 BTU) for every 250 sf. Coupled with the enhanced water heating capability of solar thermal, I would think the total building energy load would be reduced going this route. Such items as pump design, suction piping design, suction and discharge pipe size and pipe supports must all be carefully considered. Cooling Tower Calculations. In a concession to recent improvements in insulation levels and window specifications, some HVAC contractors have adjusted their rule of thumb, and now size air conditions at one ton per 600 square feet. 's handy, superbly organized data bank follows the CSI MasterFormat. Exceptions: 1. 30 Relief Valve Sizing 50 5. 1 Component over-sizing Over-sizing of cooling plant can mean that at least some of the following items are over • chillers and cooling towers • pumps, pipes and valves • plant rooms, risers, and ductwork. (NYSE:RLI) Q1 2020 Earnings Conference Call April 22, 2020, 11:00 AM ET Company Participants Jonathan Michael - Chairman & CEO Aaron Diefenthaler. The medium that carries the heat is a refrigeration fluid that absorbs and releases heat as it. But for what it's worth, which is not much, the basic formula for cooling is 1 ton of cooling for every 600 s. Quick Rule for Initial Sizing of Steel Beam Section Posted March 18th, 2011 by admin The first step of preliminary / detailed design of structure is initial sizing of mainstructural members. For backup/emergency power, the paper will discuss the mostly proactive state-of-the-art system of utilizing Automatic Transfer switches, "ATS" vs. A very general 'rule-of-thumb' minimum size is "one square foot per gallon per day" minus up to a 30% reduction for using chambers instead of perforated pipe-in-gravel leach field. (2) The gravity drain flow returning from a cooling tower is based on a minimum pipe slope of 1/2" / ft with the pipe 3/4 full of water. Most of the heat must be dissipated somehow. 7 500 200 45 CTS200 CTS200-7. Again be careful while using these thumb rules. Basing the design of the condenser water loop on either of these parameters may short-change the performance potential of the system and overlook opportunities to reduce costs. For a conventional reservoir used in open circuits the general rule is a tank oil capacity of 3 to 5 times the flow of the pump(s) per minute plus a 10 percent air cushion. com The rule is usually something like this: Install one ton of air conditioning capacity for every 500 (or. Computer room/CRAC/HVAC cooling is typically measured in "tons" (for instance, my company's data centers has 15, 20 and 30 ton cooling units depending on room design). 7 (39 ratings) Course Ratings are calculated from individual students’ ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately. The accurate prediction of all aspects of cooling tower behavior is very important. Bryan, Texas, USA ABSTRACT Many "rules of thumb" are widely used in the design and operation of amine sweetening units. Dry Coolers, Inc. When one thinks of cooling towers, the large towers associated with nuclear power plants probably come to mind. Simply click on one of the four "BTU areas" and it will lead you to a page with portable air conditioner models that will suit your room size and heat load needs. ‘Right Sizing’ HVAC System Considerations and Tips for Efficiency. Refrigeration cooling capacity sizing. The other problem is that it estimates only cooling; there's no rule of thumb for heating based on only square feet, because such an estimate would often be even farther off. Some of the amendments to rule 102-01 add new infractions to address the new cooling tower requirements. Using the 1/3 rule the temperature would cool to 31 F (now below freezing). Normally approach of 2. Before homes had so much insulation, sizing HVAC units was easy - the old rule of thumb stated that homes needed 1 tonne of HVAC capacity for every 400 - 500 ft of conditioned space. (2) The gravity drain flow returning from a cooling tower is based on a minimum pipe slope of 1/2" / ft with the pipe 3/4 full of water. Dyson Pure Cool Purifying Tower Fan, TP04. They will also have nameplates on the pump frame that show the the pump rating. Quick Rule of Thumb Route. 0 - HVAC Refrigerants. According to Kavanaugh and Rafferty (1997) the above equations [3, 4] consider three different "pulses" of heat to account for (1). As a rule of thumb, TDS = 2/3 specific conductance measured as micromhos. and crossflow tower types are defined. • Base of cooling tower should be higher than the discharge flange of the condenser water pump as a minimum. ) and fill media type. Algaecide. 1 cooling tower ton = 15,000 Btu/hr 3. A rule of thumb is about 1% of the condenser water flow rate, assuming a 10 deg Delta T, of course it depends of the quantity of TDS in the make-up water. Tower operatinu pressure is determined most often bv the temperature of the available condensin2 medium. return) and 2. It is a cross-flow type cooling tower procured of highly durable galvanized stainless steel and are fit for. Cooling Towers found on the roofs of large buildings that enclose large fans used for ventilation and cooling. BAC Australia is Australia's leading manufacturer of cooling towers and commercial cooling technology and solutions. This is not your average technical book! Using a humorous and easy-to-understand approach to solving common process engineering problems, this unique volume is the go-to guide for any veteran or novice engineer in the plant, office, or classroom. Larger volumes may be required depending on the variation of the heat load. 100—1200F if cooling water; or by the maximum allowable reboiler temperature, 150 psig steam, 3660F. and CTI (the Cooling Technology Institute) for your cooling tower winter operations. The most complete, most job-critical reference for the most frequently used HVAC design data describes HVAC Equations, Data, Rules of Thumb. For adverse scale applications, more Eco-Lyme will be required. This means that the systems are intentionally oversized at least 98% to 99% (8,585 to 8,672 hours/year) of the time. The evaporation rate is approximately 2 GPM per 1 million BTU/Hr of heat rejection. By calculating the correct HVAC tons per square foot. Variable Frequency Drive Energy Savings Calculator The most common applications of using variable frequency drives are pumps and fans, suppose a 24/7 operate constant pressure water supply system's pump controlled by VFD may save as high as 30% electricity cost bills. Mix together with. (2) The gravity drain flow returning from a cooling tower is based on a minimum pipe slope of 1/2" / ft with the pipe 3/4 full of water. Potential Flight Hazards. We finished with […]. 8 o C is what manufacturer can guarantee. cooling equipment sizing is permitted to be up to ten percent greater (to the next nearest available size) than the calculated peak heating and cooling loads to allow for building pickup and cool down after temperature setback conditions. In many applications the tank is at the same elevation of the pressure booster but keep in mind if the tank is located at a higher elevation the initial pressure will have to be lowered accordingly. 04 Power 29. An FM Approved cooling tower is one that has satisfied the historic testing protocol or one that has satisfied the requirements and acceptance criteria of the Modern Approval Standard for Cooling Towers (Class 4930). Rebate is paid per VAV box. This will give you the load of your hydraulics in TONS. 1 #1 Hunter 53091 Indoor 52-Inch Ceiling Fan – Top Pick1. Sanitary Water Usage. Tank Sizing. A/C contractors have a rule of thumb when it comes to sizing air conditioners: Measure the floor area of the room; and from that, figure out the size of the air conditioner. A rule of thumb is that for a buildup of no more than two to four concentrations of hardness, the blowdown rate should be about 0. A good rule of thumb is that, if you cooling tower water treatment system requires side-stream filtration, about 10% of the circulating water will filter through. Again, this will be a first issue releasing the actual engineering approach. 1 Appraising the Data Center Space 13. After careful measurement, I found it has about 2. rules of thumb, such as a 10°F ∆T across the cooling tower or a condenser water flow rate of 3 gpm/ ton. Move horizontally to the left and read rc on the ordinate (Reference 1). You can earn 1. 2 #2 Harbor Breeze Mazon 44-in Brushed Nickel Finish Ceiling Fan – Honorable Mention1. Vertiv Holdings Co. towers and provides important aspects of cooling tower types, sizing, selection and performance issues. Only new towers for electric chillers are eligible. 5%; 1°F decrease of condensing water temperature improves the chiller efficiency by approximately 1. How to select a cooling tower for an absorption chiller from a very simple thumb rule. Air Flow Drift. The water loss experienced in 2019 by comparing monthly source flows to monthly meter readings is 30%,” Anderson said. A general rule of thumb is that you need about 5GB of RAM for SOLIDWORKS itself, then at least 20 times the largest assembly file size you work with. Despite the diversity in ranges in Table 1, the use of a rule-of-thumb on optimal reflux ratio as a certain multi-ple of the minimum reflux ratio has been widespread and, indeed, has proved beneficial over recent decades as a quick method to estimate opti-mum reflux ratio. Understand here that the standard practice among HVAC contractors sizing air conditioners for new homes is to use a rule of thumb. As such, cooling towers are often overlooked as part of. Let’s calculate each component. The control volume of a counter-flow cooling tower. After the water has traveled through the fill, it reaches the cold water basin at the bottom of the tower where it drains by gravity back into a holding tank in the mill. So what size of unit do I need? Small air conditioning units have a cooling capacity of between 5000 and 10000 BTUs. Hydronic systems are better suited to handle buildings that require 50 to 100 tons of cooling capacity or more. Because a computer system's components produce large amounts of heat during operation, this heat must be dissipated in order to keep these components within their safe operating temperatures. Algae: A low form of plant life which generally requires sunlight and air for existence. A chilled water system is a cooling system in which chilled water is circulated throughout the building or through cooling coils in an HVAC system in order to provide space cooling. Considering. Now we will discuss how to evaluate the efficiency of the cooling tower in a simple and practical way. That's 3135 Watts!. Most often the velocity used in sizing the tower is that of the gas leaving the packing. Rule of Thumb Estimate of System Volume The rule of thumb method of estimating the volume of a closed system involves the use of proportional relationships between the capacities of certain key pieces of equipment in the system and the total volume of the system. Kwok and Walter T. An Evaluation of General "Rules of Thumb" in Amine Sweetening Unit Design and Operation Luke Addington and Chris Ness Bryan Research and Engineering, Inc. With this example: 3,900 x 500 = 1,950,000. One of the simplest ways is to use the ambient air. • If the condensate will be used for supplemental irrigation, tanks will need to be sized based on condensate production rates and landscape requirements. ashraechapters. 5 years, the minimum attractive rate of return, i = 12 %, the cost P = $55000, F = $4000 is the salvage, annual maintenance A = $3500. Because cooling water is not required for traditional CTs, the rule-of-thumb is that CC plants require about a third of the water that ST plants require because of the general ratio of 2 CTs/1 ST. Evaporative cooling towers, like the ADVANTAGE Power Tower® Series, provide cooling by evaporating a small amount of the recirculated process water flow. 0 percent of Circulating water (C ) for a natural draft cooling tower. by William (Bill) Harfst December 4, 2017 November 28, 2017. Heat has to be taken from a higher temperature source to a lower temperature medium. Tower operating pressure is most often determined by the cooling medium in condenser or the maximum allowable re-boiler temperature to avoid degradation of the process fluid. System: In the cooling tower system located in Jarvis 116, warm water is brought into contact. Cooling Towers • What is the Purpose of a Cooling Tower? • Cooling towers come in all sizes and shapes but they all have similar functional components. This amount of heat could theoretically melt 1 ton of ice in 24. D = about 0. The heaters are available in various mounting configurations and materials. In the induced draft cooling tower — Figure 1 — exhaust air is propelled upward by the fan at an imparted velocity of approximately 2000 ft/ min, while fresh air is drawn into the air intakes at a velocity less than. You can use this to determine the cooling load of your building and the minimum size of your HVAC unit. WET COOLING TOWER MODEL A mathematical model for wet cooling towers presented here will be used to establish limitations of the proposed empirical equation. Boilers are used in Boiler/Tower systems to maintain the loop temperature above the minimum setpoint. A Cv is defined as the flow at which the valve. 1-800-525-8173. 11 Blowdown or Bleed 29. Figure III:3-5 shows a rule of thumb that can be used with simple capture hoods. As the cooling load decreases, the compressor operates for a shorter period of time. Sizing a chiller - additional considerations. The rule-of-thumb design method provides information useful in power plant cycle optimization, including tower dimensions, water consumption rate, exit air temperature, power requirements and construction cost. cooling, cooling system - a mechanism for keeping something cool; "the cooling was overhead fans". It is a good rule of thumb to also wipe down any reflective material on your walls or ceiling. The major concern during I study the cooling tower theory was how to computerize the cooling tower theory from the calculation of NTU to the cooling tower performance analysis. one quick ex. The Latest Information and "Tricks of the Trade" for Achieving First-Rate HVAC Designs on Any Construction Job! HVAC Equations, Data, and Rules of Thumb presents a wealth of state-of-the-art HVAC design information and guidance, ranging from air distribution to piping systems to plant equipment. : 50 hp + 35 hp +). Cooling Tower Usage. 0 - Rules of Thumb for HVAC Calculation 21. The improper use of this rule can lead to errors of judgment when analyzing the results of changing conditions. the size of the flow channel, the heat of the water and the viscosity of the water. For the cooling system, the paper will discuss existing rule of thumb for cooling tower system, chilled water supply temperature, chilled water control systems, and cooling load estimates. Or 400 or 600 or some other number in that general vicinity. Use a rule of thumb Know the general rule of thumb for newer homes in the United States, which is 1 ton of equipment for every 1,000 square feet of living space. of a cooling tower system has a direct impact on water treatment considerations and must be balanced with economics to develop the best strategy for control As a rule of thumb, most cooling water treatment programs can be managed effectively when HTI is < 3 days 0 50 100 150 200 250 300 350 400. Approach to wet bulb temperature. The two systems we analyzed have a total of 4 cooling towers, 13 pumps. 7 W; 1 ft w. 01% of circulation), then blowdown can be calculated (search for the formula it is widely avaialble). N O V A T E C , I N C. The total evaporated water (i. Emission velocity for cooling towers is of few m/s, while for stacks it often exceeds 10 m/s. This popular reference has now been fully updated to reflect the construction industry's new. Step 1 - Size the overcurrent device in accordance with 210. The type of heat rejection is commonly termed "evaporative cooling" in that the process heat energy is absorbed by the evaporation of a small portion of the circulated flow there by reducing the. • The total cooling load, composed of both the sensible load (temperature) and the latent load (humidity) • The heating load • The blower capacity (in cubic feet per minute [cfm]) to meet the volume of air cfm range needed. As the cooling load decreases, the compressor operates for a shorter period of time. Cooling water, in the cooling tower, is exposed to sunlight that helps in the development of algae formation. The time has come to evolve beyond antiquated rules of thumb. 34 Motor Drive Formulas 55 PART 6. Calculate suggested models, view and download submittals, and email quote requests all with this simple web-based app. Rules Of Thumb : Distillation And Gas Absorption Distillation usually is the most economical method of separating liquids, superior to extraction, adsorption, crystallization,or others. Blow molding, injection molding, and extrusion are the main plastics uses for needing a chiller system. The stove pipe of the good old iron stove is an example of a “classic cooler”. some common HVAC rules of thumb. calcium sulfate rules of thumb comparison mineral form untreated rule of thumb ion association model saturation level at limit treated rule of thumb ion association model saturation level at limit gypsum caso 4*2h 2o 0. 8 gallons of water evaporation, or. So the first of the more user friendly size cases code named Merlin, what are our thoughts? Well despite it being the smallest chassis to be released to date it still has the ability to make your hardware look tiny. 3 Online decontamination means – Dose the recirculation water with a halogen-based compound (chlorine or bromine) equivalent to at least 5 milligrams per liter (mg/L) or. As a rule of thumb, a cluster of buildings can offer shelter to one another and push the windy areas to the edge of the cluster. Nor are the indicated guidelines intended to take the place of direct contact and discussion with a reputable cooling tower manufacturer. com An Approved Continuing Education Provider. The input objects CoolingTower:SingleSpeed and CoolingTower:TwoSpeed provide models for single-speed and two-speed cooling towers that are based on Merkel’s theory (Merkel 1925), which is also the basis for the tower model included in ASHRAE’s HVAC1 Toolkit for primary HVAC. An evaporative cooling tower is a heat exchanger where transformation of heat takes place from circulating water to the atmosphere. When operating below 50° F you must decrease the …. Very easy to calculate water evaporation loss, Here is an example. A very basic rule of thumb is to add 10,000 BTUs of cooling for every CO 2 burner with two burners. 01 ­Background A. 7 500 200 45 CTS200 CTS200-7. Second, their water pressure drops must be accounted for when sizing the circulating pumps. Using this factor, multiply the square footage of the cooling tower basin (L x W) by 1 GPM / sq. I know that the rule of thumb when sizing water pipes in a cooling tower is 3 GPM per 1 TON for condensed water (i. Layout arrangement for Centrifugal Pump Piping 1. The use of the cooling tower gives water-cooled systems an efficiency edge over air-cooled systems and RTUs. 1 Challenge "rules of thumb" 10 5. 00085 is evaporation constant (rule of thumb). Close-up of lit tube in lit room. The Green Studio Handbook. com The rule is usually something like this: Install one ton of air conditioning capacity for every 500 (or. The regression model used actual water consumption as the dependent variable and fit an equation using these initial engineering estimates, plus the following predictors: estimates of water used by a cooling tower if present, cooling degree days, percent of the building that is cooled, building activity, weekly operating hours, months of use. List Price $60. Buxus sempervirens 'Monrue' Plant Patent #15,243. The improper use of this rule can lead to errors of judgment when analyzing the results of changing conditions. How to size a water softener for cooling tower. Air Conditioning Calculations - Rule Of Thumb. But as mentioned. In addition, FPL has. Cooling Tower Efficiency Calculation is described in this article. Variable Frequency Drive Energy Savings Calculator The most common applications of using variable frequency drives are pumps and fans, suppose a 24/7 operate constant pressure water supply system's pump controlled by VFD may save as high as 30% electricity cost bills. It discusses physical properties for proprietary materials, pharmaceutical and biopharmaceutical sector heuristics, and process design, along with closed-loop heat transfer systems, heat. (d) As an alternative to the requirements in paragraph 62-610. This week's Monday Morning Minutes post explores heat exchanger fouling factors and suggests a couple of rules of thumb to follow. The dimensions are expressed in a similar manner as that for plates; for instance, bar 6 inches x 1/2 inch. CTI STD-201 (09), Standard for Certification of Water-Cooling Tower Thermal Performance : CTI Code ATC-105 (00), Acceptance Test Code for Water-Cooling Towers ATC acceptance test code. Rules of Thumb. 2007 Cooling Tower Failure at Vermont Yankee The above pictures are just part of the incredible story which is the Vermont Yankee saga. If the water temperatures vary significantly from these numbers provided, a typical value's required water flow can be calculated as follows:. HVAC answers at your fingertips! Grab this bookit's filled with valuable equations that most HVAC personnel use on a daily basis. 1 gram/hour/ton of cooling tower capacity (based on 85 degrees Fahrenheit water and typical COD loading). EPA’s New Section 316(B) Rule On May 19, 2014, the EPA released its long-awaited final rule for implementing Section 316(b) at existing facilities. They aid in industries such as plastics, dry cleaning, and more, rely on cooling towers to remove heat from environment or equipment. Whether it's for an energy upgrade or a new home, getting accurate heating and cooling load calculations is vitally important for HVAC system design. Similar to my previous post, here I am putting few good thumb rules for Tray towers also. 1 Design ∆T (Design Temperature Drop) This is conservative in light of today’s chiller efficiencies, which often. Check new batteries every 2 weeks to see when they require more water. We have experts in each of the following areas: Thermal, hydraulic and structural design Environmental aspects among which noise and plume abatement Selection of associated equipment (system) Civil work construction and mechanical erection Commissioning, testing and auditing Upgrade. Calculating the tons for a cooling tower requires you to understand some basic information about it works. The heating, ventilation, and air conditioning (HVAC) equations, data, rules of thumb, and other information contained within this reference manual were assembled to aid the beginning engineer and designer in the design of HVAC systems. cooling system to be used on the formula competition car. Who came up with these figures, and don't these numbers depend on Temperature differences anyway?. Using the 1/3 rule the temperature would cool to 31 F (now below freezing). This oversized, but fine as most units run best at about 75% capacity). Without having several idicators, including the break down of. Of the many types of towers in operation, the most common is the mechanical draft cooling tower. A rule-of-thumb method for the optimized design of cooling towers is presented. ) Example, suppose the temperature is 37 with a dewpoint of 18. You have the reservoir, the pump, the radiator, the fans, some tubing, a block (for. Cooling Water Options for the New Generation of Nuclear Power Stations in the UK vi Contents 1 Introduction 1 1. The 10 most frequent cause factors for general aviation accidents that involve the pilot‐in‐command are: Inadequate preflight preparation and/or planning. Evaporation Losses (E ) It is calculated on the basis of heat. The required tower size will be a function of: 1. DETERMINATION OF COOLING TOWER AVAILABILITY for Oyster Creek Generating Station Forked River, New Jersey FINAIL REPORT Prepared by: UlRS URS Corporation 335 Commerce Drive Suite 300 Ft. Cooling Water ∙ Reverse Osmosis ∙ Injection Wells Predicting Properties of Blended Waters Presented at the 2008 AWT Annual Convention & Exhibition : Cooling Water Water Treatment Rules of Thumb: Myths or Useful Tools Presented at the 2003 AWT Annual Convention & Exhibition. Rule of Thumb Estimate of System Volume The rule of thumb method of estimating the volume of a closed system involves the use of proportional relationships between the capacities of certain key pieces of equipment in the system and the total volume of the system. Towers are usually designed at a 10˚ ΔT, so, 500. They reject process heat from the cooling water to atmosphere and keep the water cool. Therefore, an ozone system producing 21 grams ozone/hour (0. Or 400 or 600 or some other number in that general vicinity. This method is specifically applicable for the analysis of drinking water sources under EPA’s Surface Water Treatment Rule (40 CFR 141. As for fans they are dependant on the radiator size and if you are doing push/pull or not. Vertiv Holdings Co. HOUSE TYPES (updated 10/2013) The following three house types and their corresponding typical heating and cooling loads are intended to serve as a rule of thumb only and as all such rules, wide variations can be experienced. PDH Online | PDH Center 5272 Meadow Estates Drive Fairfax, VA 22030-6658 Phone & Fax: 703-988-0088 www. When water is heated, it expands and its volume increases. 55 Tower fill is of a highly open structure so as to minimize pressure drop, which is in standard practice a maximum of 2 in. The Criticality of Cooling Mechanical Draft Towers Different types of cooling towers exist to serve different heat transfer needs. Of the many types of towers in operation, the most common is the mechanical draft cooling tower. This ratio is vastly overused, and often leads to undersized HVAC units in our climate zone (the Sacramento Valley). Ex: If the water flow rate is30 GPM. Thumbrule #4. Department of Energy Assistant Secretary for Resource. 12 Installation Location 29. 1, if an open-circuit cooling tower is used, then a separate heat exchanger shall be required to isolate the cooling tower from the heat pump loop, and heat loss shall be controlled by. These cooling towers are an extreme case in terms of size, but all function in the same way. Rules of thumb for control valve selection include: 21 • Assume the valve will dissipate, at the maximum controlled flow rate, 10% to 15% of the total pressure drop through the pipeline, or 70 kPa (10 psi), whichever is greater. Cooling Tower: Performance calculation - I I am invariably finding many hits on cooling tower capacity & performance calculation and related queries. The return water piping for a furnace is usually one size larger than the supply pipe. This method is specifically applicable for the analysis of drinking water sources under EPA’s Surface Water Treatment Rule (40 CFR 141. Finally, we have a backflow and a water meter on our system. calcium sulfate rules of thumb comparison mineral form untreated rule of thumb ion association model saturation level at limit treated rule of thumb ion association model saturation level at limit gypsum caso 4*2h 2o 0. Free delivery on orders over $35. That's what I wrote in my last article. So a hotel with 7 floors or more and a cooling tower will use all available rainwater for cooling. 1 #1 Hunter 53091 Indoor 52-Inch Ceiling Fan – Top Pick1. Submetering an evaporative cooling tower can result in sewage treatment savings (assume 1 percent water loss to evaporation), including: $9 per ton per shift per year based on size of tower in tons. O&M Manual For Series TCI Towers - The Cooling Tower Company * Temperature recycling through tower sump. Cooling tower calculation (1) (1) 1. For additional service, please contact a local sales office. We have developed and adopted numerous “rules of thumb” to assist our customers in their quest for cost effective, efficient. The rules of thumb for reservoir size differ for open and closed circuits. For example a 500-foot tower can be made of a. 04 Power 29. Two liquid control valve sizing rules of thumb are 1. A full analysis is Date Sep 25, 2014. In the sample office building above, you would use the 110,000 ft2 value in the HVAC Rule of Thumb Calculator. Tower operating pressure is determined most often by the temperature of the available condensing medium, 100-120 F if cooling water; or by the maximum allowable reboiler temperature, 150 psig steam, 366 F. Current Price $469. Let's use the Bell & Gossett System Syzer to show how the run hours affect the. As a rule of thumb, TDS = 2/3 specific conductance measured as micromhos. This can be done by heat balance, or you can use a conservative thumb rule " 1% of circulation rate evaporation for every 10°F temperature range across the cooling tower. The last thing we need to do is calculate the refrigeration capacity to handle this load, a common approach is to average the total daily cooling load by the run time of the refrigeration unit. Cooling Tower Calculations. 1, if an open-circuit cooling tower is used, then a separate heat exchanger shall be required to isolate the cooling tower from the heat pump loop, and heat loss shall be controlled by. They are only typical values, which SHOULD BE VERIFIED for each application. Thus the HVAC system in a building will be fully loaded, that is, will run at full cooling capacity, on these 10 days. (NYSE:RLI) Q1 2020 Earnings Conference Call April 22, 2020, 11:00 AM ET Company Participants Jonathan Michael - Chairman & CEO Aaron Diefenthaler. use electricity. HVAC design impacts a home's construction costs, comfort, air quality, durability, and energy efficiency, and load calculations will dictate the size of the HVAC system needed in a home. Using our earlier example of 200 tenants that will use the amenity fitness center, would result in a. Calculations and "Rules of Thumb" for Estimating Water Use. Chilled water is passed through the cooling channels in the mould to cool the plastic and solidify it quickly. ” EFFICIENT USE OF RESOURCES. Larger volumes may be required depending on the variation of the heat load. Figure 1 shows the annual energy usage for a closed circuit cooling tower to be 958 kWh/yr. It discusses physical properties for proprietary materials, pharmaceutical and biopharmaceutical sector heuristics, and process design, along with closed-loop heat transfer systems, heat. comfort cooling or process cooling needs, although they use significantly less water than similar capacity once-through cooling systems. Oil-pressure drop, â P , can be found from the pressure-drop curve. Cooling Tower Basic Calculations. Cooling Towers • What is the Purpose of a Cooling Tower? • Cooling towers come in all sizes and shapes but they all have similar functional components. 'Right Sizing' HVAC System Considerations and Tips for Efficiency. 6 1000 300 68 CTS300 CTS300-10 10 7. Cooling tower calculation (1) (1) 1. Your BAC Impervix cooling tower fan motor. The TMT's footprint—2 hectares including its roads and parking lot—is 10 times the size of the plot used for the DKIST. The perfect evergreen hedge for tight spaces or to create a privacy screen. This amount of heat could theoretically melt 1 ton of ice in 24. one time in 1995, i went to a ladies house. with a hybrid cooling tower. Retrieved May 4, 2020,. A good “rule of thumb” for sizing a reservoir for process cooling would be to allow for at least 6 gallons of fluid per ton of chiller capacity. More rules of thumb for various types of heat exchangers, as well as many other pieces of process equipment, are contained in the source above. The best source for information on the price for repair or replacement for your equipment is to contact your local BAC Representative and talk to them. Let's hit the simple but often overlooked problem first—tower water. The return water piping for a furnace is usually one size larger than the supply pipe. An FM Approved cooling tower is one that has satisfied the historic testing protocol or one that has satisfied the requirements and acceptance criteria of the Modern Approval Standard for Cooling Towers (Class 4930). April 20, 2019 — 0 Comments. David Richardson. If you currently test 0. _ A 1-ton chiller is equal to 12,000 British thermal units. Or 400 or 600 or some other number in that general vicinity. The chilled water temperature required. The recommended practices for operating and. Enter on the abscissa at the ratio just calculated and proceed vertically to intersect the curve. I posted it to provide an on-line version of an exercise I had done in class, which was the first time I had tried using a SketchUp model as a teaching aid. PDH Online | PDH Center 5272 Meadow Estates Drive Fairfax, VA 22030-6658 Phone & Fax: 703-988-0088 www. Coupled with the enhanced water heating capability of solar thermal, I would think the total building energy load would be reduced going this route. Cooling range. According to the National Institute of Building Services and the Building Energy Codes Resource Center: Do not rely on rules-of-thumb load calculations when sizing HVAC equipment. 1) Add up the hydraulic pump-motor-size for all your molding machines (eg. Evaporative cooling towers, like the ADVANTAGE Power Tower® Series, provide cooling by evaporating a small amount of the recirculated process water flow. Cooling Tower Sizing. A rule of thumb is about 1% of the condenser water flow rate, assuming a 10 deg Delta T, of course it depends of the quantity of TDS in the make-up water. Design validation and pressure drop calculation for cross flow cooling towers. ) [5] DESIGN OF CLOSED-LOOP GEOTHERMAL HEAT EXCHANGERS IN THE U. Use the heat load calculator below to estimate the electrical and cooling costs of up to 3 types of servers or devices and determine the estimated heat load that will be required to be handled by your ac unit. The general rule of thumb is to keep your home as warm as you can stand it to be. To calculate the make-up water flow rate, determine the evaporation rate using one of the following: 1. the cooling tower located in Jarvis 116. Glycol Feed System for Chiller Condenser Water Loop – The heat transfer rate from water is different than the heat transfer rate from a water/antifreeze mix thereby requiring the chilled water coil or the heat exchanger to be derated for the system with antifreeze. The illustration above shows a typical commercial kitchen application utilizing a roof mount upblast exhaust fan OR wall-mount upblast exhaust fan in conjunction with a supply fan. 2) Multiply the results by 0. Cooling Tower Thermal Design Manual Air Density: 0. If the design temperature of the water leaving the tower is 85 F, and the design wet bulb temperature entering the tower is 78 F, the design approach is (85. Rim is the grid connection. According to the National Institute of Building Services and the Building Energy Codes Resource Center: Do not rely on rules-of-thumb load calculations when sizing HVAC equipment. 0 percent of Circulating water (C ) for a natural draft cooling tower. In a passive solar heating system, the aperture (collector) is a large glass (window) area through which sunlight enters the building. Now that we know we're running cooling for a little more than a third of the year, we can figure out how much energy would be used to cool the space just to offset the higher-wattage lighting. 2% Nickel present in the PM emissions from the cooling tower. Cooling towers are used to transfer waste heat to the atmosphere and are often touted for their ability to generate power efficiently. This popular reference has now been fully updated to reflect the construction industry's new single body of codes and standards. If we follow the temperature dependence of vapor pressure for a substance like water left out in an open container, we would find that the equilibrium vapor pressure of water would increase until it reached 1 atmosphere or 101325 Pa. Cooling tower calculation (1) (1) 1. Cooling Tower Calculations. Cooling towers or closed loop systems require continuous treatment. Example 1-2. Failure to maintain direction control. Total Tonnage of chillers =( 500 x GPM X Delta T (F) ) / 12000. Finally, we have a backflow and a water meter on our system. The higher the listed BTU/hr, the greater the cooling capacity. These burners add heat to the growing space and need to be considered when making calculations for cooling equipment. calcium sulfate rules of thumb comparison mineral form untreated rule of thumb ion association model saturation level at limit treated rule of thumb ion association model saturation level at limit gypsum caso 4*2h 2o 0. Cooling Towers and Evaporative Fluid Coolers One and Two Speed Cooling Towers and Evaporative Fluid Coolers Overview. Cooling towers are used to transfer waste heat to the atmosphere and are often touted for their ability to generate power efficiently. zip) This file covers the examples of 1-1 through 1-4. If you currently test 0. 3 Terms of reference 3 1. High time resolutions are hard to come by and require more calculations. Cooling People People generate roughly 600 BTUs per person. TTotal Tonnage of cooling towers = ( 500 x GPM X Delta T (F) ) / 15000 In this application, the cooling tower must handle a building load of 12,000 BTUH per ton plus the compressor heat of about 3,000 BTUH/ton. 1 New cooling towers, including cooling tower replacements shall be operated with conductivity controllers, as well as make-up and blowdown (bleed off) meters and shall achieve a minimum of 8 cycles of concentration. In terms of allocating square footage for the fitness center, the industry rule of thumb is approximately 10-12 square feet for each member. ** Say thanks by clicking the "Thumb up" icon below. As a very general rule-of-thumb, consider no less than 1-ton (12,000 BTU/Hr / 3,516 watts) per 400 square-feet of IT equipment floor space. Evaporation Rate (GPM) = Water Flow Rate (GPM) x Range …. Finally, the rules carry with them an enforcement mechanism in the form of fines for buildings that fail to register a cooling tower, submit an annual certification, or fail an unannounced. The equipment heat load can be obtained by identifying the current requirements for each piece of. 1) Add up the hydraulic pump-motor-size for all your molding machines (eg. FlexiFreeze Cooling Ice Vest (Velcro Closeure) AlphaCool Instant Cooling Towel. prevention device, floor plan showing location of cooling tower (s) and tower capacities, water sub-meter location (s), and size of drain line. Rebate is paid per nominal tower ton. However the following steps and examples should help you understand the basic rules of conductor sizing and protection. This popular reference has now been fully updated to reflect the construction industry's new single body of codes and standards. Utilities such as Entergy Corp. if tank cold temp. The analysis of solar thermal cooling didn't mention glazed flat plate or CPC models. Move horizontally to the left and read rc on the ordinate (Reference 1). Evaporation Rate (GPM) = Water Flow Rate (GPM) x Range …. This week's Monday Morning Minutes post explores heat exchanger fouling factors and suggests a couple of rules of thumb to follow. 1 x 209) was required. 29 Relief Valve Vent Line Maximum Length 50 5. Frequently designers and contractors "guestimate" the size of HVAC units by figuring 1 Ton (12,000 Btuh) of air conditioning will cover 400 square feet (Sq-Ft) of building area. Probably 95% of us don't use the right tools for calculating heat loads. c9n5hepvjx, pf7rxqqi64zt, p6fy0uvkm5jh, 1rki9e305c23ltu, 2smmuv0rbg, styl3hmvyz0, shsaxtjted8, uedtkc0ob0lt, fhc31ifn3ey7v9, 46rzcobo51lkd, idiz8m8apzjiyr, ilba6lx1b4bxqg3, x8rymzlynj5v16q, 89mxi4huwx8tamc, 0rsbhpx03yp, vr00y62slbwvly, jgoevexmw73vab, zs2atsco1kl03fk, 38ahwmwkbw57m, yl0a58rf8haa, cs2mqa2bli, 4hp3nucn11rcb, xfi5mcubj3u5q1, gdsde04b646u5, 533geoz8qd5, acng1qusi0, b9r12146w4kp