An example of a mass and energy balance on the laboratory cooling tower will be presented along with the results of experiments in which the rate of heat dissipated by the tower was calculated at full. Introduction the laboratory cooling tower is a cooling tower unit from a commercial air conditioning system used to study the principles of. Cooling towers can cycle water numerous times before the water becomes saturated and must be discharged out of the system. Process results and conclusions cools water by exposing the water particles to air actually perform the experiment better predictive equations 20% heat transfer more consistent temperature reading equipment 80% mass transfer cooling tower experiment system set up objectives. Our lab scale cooling tower is designed to mimic an industrial operation, except. Most of the droplets were collected on the first stage of the cascade impactor and, there fore, exceed llu m in size. Cooling towers summary the cooling tower removes heat from water used in cooling systems within the plant. In practice this heat is removed via a condenser that transfers the heat to a cooling water circuit see figure 1. Lab 1b cooling tower performance and sensors for thermal. Cooling towers with open and closed water circuits are available. Understanding the basics of cooling tower heat transfer. Cooling tower operation forced draught cooling towers use the evaporation of a liquid often water into air to achieve cooling. Range hot water temperature cold water temperature cooling tower efficiency calculation. Cooling tower maintenance program and plan template.
A very important concept for understanding cooling tower heat transfer is that of wet bulb temperature, which is the lowest temperature that can be achieved by evaporative cooling. Warm water is pumped from the load tank through the control valve and water flow meter to the column cap. Cooling towers overcome most of these problems and therefore are commonly used to dissipate heat from watercooled refrigera tion, airconditioning, and industrial process systems. Design and fabrication of cooling tower dileep kj1, dileep kumar baniya2, anoop chandran kurup3, arun varghese4 1234department of mechanical engineering, bangalore technological institute,india abstract.
Each year, specify person or title will certify to the department of health, that all cooling towers were inspected, tested, cleaned, and disinfected in compliance with the doh regulations, that the condition of the cooling towers is appropriate for intended use, and that a maintenance program and plan has been developed and implemented. The purpose of a cooling tower is to keep a process from raising temperatures too high were they either can be dangerous or lower the efficiency. It is therefore extremely important to properly prepare a surface to receive protection, then quickly and completely apply the protecting media to effectively protect that surface. In a cooling tower of infinite size and with an adequate air flow, the water outlet will be at the wet bulb temperature of the incoming air. Cooling tower outlet temperature is called cooling tower range.
Jea, as the control authority, is required to regulate cooling tower discharges to the potw. The tower often consists of a sprinkler system which wets a highsurfacearea substrate plates continuously, while air flow through the chamber converts liquid to vapor. A basic understanding of the system water distribution shall be established in order to properly operate and maintain a cooling tower on a water efficient manner. Blow down is a term for water that is removed from the. Combining the mass flow equations with the energy equation leads to the final equation relating the mass flow rate of the dry air to the circulating cooling water of. Fog can be presistent in the river valleys during the colder months. A cooling tower is a specialized heat exchanger in which air and water are brought into direct contact with each other in order to reduce the waters temperature. Legionella testing is used to validate the effectiveness of your control measures. Cooling tower lab report there is document cooling tower lab report available here for reading and downloading.
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. By using a cooling tower, the plant is kept safe and operational. All of the required measured values are acquired by sensors and shown on digital displays. Doc cooling tower lab report sem yong hao academia. The term cooling tower is used to describe both direct open circuit and indirect closed circuit heat rejection equipment. Cooling tower basics calculation formulas cooling tower. After its temperature is measured t5, the water is. Cooling tower experiment supplement august 31, 2011 follow the same procedures outlined in the cooling tower performance experiment 1 except in our case we will be using the cooling tower in the university power plant. Thermal sciences design and lab, fall 2017 cooling tower due oct 26 at.
Defining cooling towers a cooling tower is a unit that recirculates water to make the inside of a building cooler. Abstract this experiment was conducted to perform energy and mass balance on the cooling tower system and to observe the. View lab report cooling tower from che 465 at universiti teknologi mara. Pdf cooling tower experiment jayden trotter academia. Types and performance evaluation, efficient system operation, flow control strategies and energy saving opportunities, assessment of cooling towers 7. Experimental study of cooling tower performance using ceramic. For the sake of this document, cooling tower systems include open recirculating circuit coolers, fluid coolers, and evaporative coolers, closed evaporative condensers. The power transfer was calculated from this experiment of cooling load for 0. Exp 7 cooling tower report final chee2820 uon studocu. Wind speed averages between 8 to 10 mph and is predominantly from the west. Because the cooling tower water supplies were neutralized, the presence of acid droplets in the plume is a priori evidence that sulfur dioxide from the stack gases had reacted with the moisture in the cooling tower plume. Best management practice and guidance manual for cooling towers.
Cooling towers are used to reject heat through the natural process of evaporation. The hybrid cooling tower can serve not only as a dry heat exchanger but also as a wet cooling tower. Cooling tower efficiency is limited by the ambient wet bulb temperature. In the wl 320 open wet cooling tower, water is sprayed into the tower from above and distributed as widely as possible using baffles. Cooling tower performance and sensors for thermalfluid systems. This report is available at no cost from the national renewable energy laboratory at. Cooling tower discharges present a potential problem to the treatment of sanitary sewer and sludge quality especially for the biosolids reuse facility. Cooling tower experiment by becca peltzman on prezi. Nalco water will work with you to design a program from our complete line of oxidizing and nonoxidizing biocides, algaecides and biodispersants. The mechanical draft cooling towers are very much similar to that of the natural draft cooling towers.
Cooling tower maintenance is more than simply biological monitoring, a maintenance plan also has to address other issues such as the condition of the equipment, condition of the mist eliminator, general corrosion, conductivity, sedimentation, control mechanisms, etc. Experimental study of cooling tower performance using. In this article explained about basic concepts of cooling tower, types of cooling towers, formula for cooling tower efficiency. Mee 491 cooling tower lab introduction the second law of thermodynamics requires that power plants i. Cooling towers are often part of a buildings heating, ventilation and air conditioning hvac system.
This experiment had several parameters that can be adjusted to observe the effects on the evaporation of water. The authors of the report would like to thank the following individuals that provided support to. Lab result shows existence of legionella more than 1 one c. As this occurs, a small volume of water is evaporated, reducing the temperature of the water being circulated through the tower. Unit operations lab cooling tower experiment youtube. Two cooling towers serve each power generating unit. Miscellaneous mechanical components doehdbk1018293 cooling towers summary the important information in this chapter is summarized below. Hilton h891 bench top cooling tower and its operating principles. From the data obtained, we have calculated the changes in temperature for each power supply for experiment 1 and the cooling range and heat load for experiment 2. Nuclear plants would be particularly impacted by a cooling tower mandate because re. Closed circuit systems differ in that the return fluid often water, or sometimes water mixed with glycol circulates through the tower structure in a coil, while cooling tower water recirculates only in the tower. The loss of efficiency and generation capacity means that less electricity is available to meet demand or to serve as reliable reserve capacity. Side stream filtration for cooling towers prepared for the u.
Air enters at the ambient condition point a, absorbs heat and mass moisture from the water. To do this, a small pump is installed to circulate cooled water from the load tank drain point, through the process requiring cooling, and then back to the water distributor at the top of the cooling tower. Types of cooling towers natural draft and mechanical draft. Cooling tower lab report free download as pdf file. System components include piping infrastructure, valves, pumps, heat exchangers, the cooling tower structure, and cooling. This type of cooling tower is 2030% more effective than the spray type. Ambient air is blown into the cooling tower in the opposite direc. The wl 320 wet cooling tower is intended to demonstrate the qualitative and quantitative functioning and characteristic variables of a cooling tower. The cooling tower must be adequately sized to reject this same amount of heat to the atmosphere. If the drying rate of 6 m3 of red oak lumber is 4 kghour, determine the kw of refrigeration required. Report the approach and range for the cooling tower under your exper imental operating conditions. Lab 1b cooling tower performance and sensors for thermalfluid. Cooling towers are a very important part of many process plants.
Cooling tower bureau of energy efficiency 5 syllabus cooling tower. Baltimore aircoil company cooling towers, evaporative. Osha states, cooling towers should be cleaned and disinfected at least twice a year. This system sends cooling water out of the equipment and into a pond or cooling tower, which is open to the atmosphere. The heat is released to the air rather than to a lake or stream.
It is then combined with makeup water, which replaces the evaporated water, and is sent through the system again. As the name indicates, air is circulated inside the tower mechanically instead of natural circulation. The water cooling tower may be used to demonstrate industrial practice in which a cooling tower is used to cool water from a process. The parameters are flow rate of water, temperature, power of heater, relative humidity and. There you can do the necessary calculations and construct the necessary graphs with ease. Cooling tower passivation corrosion of metal can be prevented through the use of an effective protective barrier. Apr 29, 2016 this feature is not available right now. Both types function as heat exchangers based on the counter flow principle. Cooling tower lab report heat transfer air conditioning scribd. This lab experiment focuses on the cooling water circuit. Determine at a water to air mass flow ratio of 1, how the range, and the approach vary with increasing water flow rate. Chemical treatment of water for cooling and heating systems. Pdf design and performance analysis of the cooling tower in the.
A cooling tower is a specialized heat exchanger in which two fluids air and water are brought into direct contact with each other to affect the transfer of heat. The file extension pdf and ranks to the documents category. Here evaporation occurs, removing heat along with the evaporated water. Ce427 chemical engineering laboratory iii fall 2005 cooling tower objectives. In a cooling tower of infinite size and with an adequate air flow, the water outlet will be at the wet bulb temperature of the incoming. Experimental the tested cooling tower is a forced draft counter. The hybrid cooling tower is a combination of the advantages of a wet and a dry cooling tower. Best management practice and guidance manual for cooling. Drift eliminators are installed to prevent water entrained in the air from leaving the system. Disinfectionquarterly legionella test by the mentioned lab is required on each cooling tower. The remainder of this report will explain the theory behind the operation of a cooling tower and how the laboratory cooling tower is operated. Technical reference for water conservation in cooling towers. This requires a rapid response, accurate detection and a tailored program to control biological growth. Cooling towers are constantly exposed to environmental contaminants and bacteria.
A pc is used to evaluate the results of the experiments. The heat picked up in the heat exchanger is returned to the cooling tower where it is rejected to the atmosphere by evaporative and convective cooling. Abstract this experiment was conducted to perform energy and mass balance on the cooling tower system and to observe the effects of one of the process variables on the exit temperature of water. Use the download button below or simple online reader. Cooling tower performance basic theory and practice. Baltimore aircoil is the leading global manufacturer of cooling towers, closed circuit cooling towers, evaporative condensers, and ice thermal storage systems. Cooling tower evaporative cooling system measurement. Technical reference for water conservation in cooling towers 1st edition. Cooling tower operation forced draught cooling towers use the evaporation of a liquid often water into air to achieve. A psychromehic analysis of the air passing through a cooling tower illustrates this effect figure 2. The effects of the process variables were observed on the exit temperature of water. The laboratory cooling tower is a cooling tower unit from a commercial air of this report will explain the theory behind the operation of a cooling tower and how the it is then carried by another hose to the top of the cylindrical cooling tower. The water that is evaporated at the cooling tower is pure, that is, it doesnt contain any of the dissolved minerals present in the makeup.
Warm recirculating water is sent to the cooling tower where a portion of the water is evaporated into the air passing. Natural draft cooling towers dissipate the waste heat at keystone. The purpose of a cooling tower is to conserve water. The cooled water is then recirculated and thus, recycled back into the system. The laboratory water cooling tower is conducted to study the performance at differences range of cooling load and inlet temperature of cooling tower. Department of energy federal energy management program by pacific northwest national laboratory x.
Cooling tower efficiency calculations cooling tower approach. Cooling tower calculations water technology report. In a cooling tower, heat is transferred into the gas stream at the gas liquid interface by. Over the operating temperature range of the cooling tower, c. Dec 04, 2017 the purpose of a cooling tower is to conserve water. If you read this book carefully, you can make any cooling tower design programs by yourself.
Since no work is done and no heat transfered externally, the cooling tower energy equation reduces to an enthalpy balance equation. Lab 1b cooling tower performance and sensors for thermalfluid systems objectives warning. Cooling towers are heattransfer units, used to remove heat from any watercooled system. The water consumption rate of a cooling tower system is only about 5% of that of a oncethrough system, making it the least expensive system to. The term induced draft denotes that air is drawn by fans through the flow of falling water and up and out of the cooling tower. Again, this will be a first issue releasing the actual engineering approach.
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