Proceedings of the 2 nd international conference on current trends in engineering and management icctem 2014 17 19, july 2014, mysore, karnataka, india 9 static and dynamic analysis of hyperbolic cooling tower sachin kulkarni 1, prof a. Based on it a genetic algorithm optimization technique was developed. Frame and casing, fill, cold water basin, drift eliminators, air inlet, louvers, nozzles and fans. Different modeling, analysis and design techniques are. Full page fax print structural engineering forum of india. The present paper represents a complete collection of the studies done for cooling towers and would give an updated material for the researchers and design engineers in the field of hyperbolic cooling towers. In the natural draft cooling tower, the necessary air mass flow is caused by density differences buoyancy. Theres no universal rule regarding cooling towers that everyone has to follow. The objective function is set to be the minimum weight of the tower. In this paper, a simple differential equation for counter flow wet cooling tower is solved analytically taking into consideration the nonlinear dependency of the saturated air enthalpy on temperature. Find the equation of the hyperbola that models the sides of the cooling tower.
Intent in the foreword of cooling tower fundamentals published by marley cooling technologies, inc. The cooling tower must be adequately sized to reject this same amount of heat. The method allows analytical calculation of cooling tower. The narrowing effect of the tower helps with the laminar flow of the evaporated water as it rises. Design of mechanical draftcooling tower and determination of. Our detailed design solutions include methods for removal of concrete that is no longer. A cooling tower is a heat rejection device which rejects waste heat to the atmosphere through the cooling of a water stream to a lower temperature. To capitalise upon the inherent energy efficiency of cooling tower systems the condenser water, and cooling tower systems must be properly designed, operating correctly and regularly maintained. Department of energy idaho operations office idaho national engineering laboratory this is an informal report intended for use as a preliminaryor working document work supported by the u. Research article thermal design of cooling tower ronak shah. The study was to formulate a tool that is applicable of achieving an optimum shape and design of hyperbolic cooling towers by coupling nonlinear finite element model. Test your knowledge on cooling tower online quiz chemical.
The design of the distribution system affects the pump head to bring the hot water to the tower inlet. Since the cooling towers are based on the principles of evaporative cooling, the maximum cooling tower efficiency depends on the wet bulb temperature of the air. Here we discusses hyperbolic stack natural draft cooling towers. As this differential is being made the form of the tower itself, the hyperbolic form, induces current upwards. F o r m u l a s a n d t a b l es formulasandtables fanlaws. What makes the cooling successful is the height of the tower. Cooling tower design calculations posted in student. Analysis is performed using available computer programs. There is also the option of counterflow and crossflow design there also exists cocurrent flow but it is seldom used. We have developed a program, useful and easy to handle, for the quick and secure design and calculation of a cooling tower project.
Hyperbolic cooling towers are a major element of circulating water systems in many power generation plants. Cooling tower design and construction designing buildings. Most residential air conditioning systems do not use the cooling tower because this cooling tower requires maintenance which will take a. The merkel equation the fundamental equation of heat. The water falls and collects in a pond at the base of the tower, formed by a base slab and the pond wall. By alok kumar swain mechanical engineer brmiit bbsr 2.
With this design, the tower is mounted on legs, providing easy access to the fans and their motors. Figure 5 shows the function of a natural draft cooling tower with closed and opencircuit cooling systems. Cooling tower design calculations student cheresources. On this channel you can get education and knowledge for general issues and topics. The cooling tower manufacturer makes these in a way that offer less space than a crossflow, and their compact design increases the overall maintenance cost. I know the inlet and outlet temperature of water, volume flow rate of water and the heat load desired from the cooling tower. The overall efficiency of a cooling tower is directly related to the design of the towers water distribution and heat exchange surface. This section discusses hyperbolic stacknatural draft cooling towers, such as the one shown above in the animation.
The towers involve considerable amount of design work on structural aspect. In consideration of the uncertain factors, a hyperbolic cooling tower with initial geometrical imperfections is studied by the pds module in ansys. The shape of hyperbolic cooling towers accelerates the influx of air improving cooling. Hi, i am an engineering student, and i am working on a cross flow induced draft cooling tower. Natural draft cooling tower an overview sciencedirect. Compared with the mechanical draft system, the advantage is that the natural. By leveraging this experience we provide our clients with innovative turnkey solutions while keeping cost and performance. A hyperboloid of one sheet is a doubly ruled surface, and it may be generated by either of two families of straight lines. Pdf the present day hyperbolic cooling towers are exceptional structures in view of their sheer size and complexities. A cooling tower is an enclosed device, designed for the evaporative cooling of water where hot water gets cooled by direct contact with air.
The mae west sculpture is a doubly ruled surface hyperboloid structure, munich, germany, 2011. The wetbulb temperature is a type of temperature measurement that reflects the physical properties of a system with a mixture of a gas and a vapor, usually air and water vapor. So, in reality, natural draft cooling towers, also known as hyperbolic cooling towers, are simply very large water coolers that represent the greenest part of nuclear or fossil fueled by coal or oil power plants because they prevent thermal pollution while providing the cooling needed for generation of electricity. Here we explain in full detail how does a cooling tower work, cooling tower working principles with example text, pictures and diagrams. If it is not available it may be assumed as for natural draft cooling tower d 0. Introduction reinforced concrete cooling towers composed of shell structure, supported on columns with ring beam type of. 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 present day hyperbolic cooling towers are exceptional structures in view of their sheer size and complexities. Elevation should be set to the elevation of the bottom of the basin of the cooling tower. Cooling towers hyperbolic stack natural draft cooling.
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. 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. Keywords hyperbolic cooling towers, earthquakes, wind, nonlinear behavior, buckling, collapse, interference. Various loading conditions on the tower such as wind, earthquake, thermal, and selfweight, are considered and their effects are combined and compared. Natural draft cooling tower design and construction in. Determination of optimum height for counter flow cooling tower. An introduction to water cooling towers ced engineering. Research article thermal design of cooling tower 1ronak shah, 2trupti rathod 1 address for correspondence 1student, 2 asst. The design of cooling tower is based on merkels method. This means they are most suited to purposedriven structures such as cooling towers. However, the most common sight, especially in power plants and nuclear plants, is hyperboloidshaped cooling towers. Pdf a survey on hyperbolic cooling towers researchgate. It also requires water treatment and has to be cleaned twice a year. Air flows in to the tower through openings in the bottom, and cools the entering hot water.
Often, the big hyperbolic cooling towers made of concrete, see figure 1. In our project we are going to design circular cooling tower named as induced draft cooling tower. Cooling tower, draught, design, hyperbolic, modeling, systems. Keywords hyperbolic cooling towers, earthquakes, wind. Natural draught hyperbolic cooling towers are the characterizing land marks of power station. The cooling tower itself should be modeled as a tank with design data entered through the tank property grid as shown in figure 3. Such a design strategy has been employed for the worlds tallest cooling tower at the niederaussem power plant in germany, with an overall height of 200 m and thickness values of 2224 cm. In naturaldraught cooling towers the open structure at the base. With air flow rate, cooling tower performance increases. One is an external circuit in which water is recirculated on the outside of the second circuit, which is.
The static and dynamic analysis of hyperbolic cooling tower. Solving applied problems involving hyperbolas college. Analysis and design of strengthened hyperbolic cooling. The tower characteristic is determined by the ratio of range and logmeanenthalpy difference. The at brings marquee features that make it the better choice in cooling towers.
The high taller and thick shell of the structure contributing high dead loads on the structures. If you read this book carefully, you can make any cooling tower design programs by yourself. Determination of optimum height for counter flow cooling tower ashraf kotb department of mechanical power engineering, ain shams university, cairo, egypt abstract a model for counter flow cooling tower is present with treatments to recover the simplifications in the literature. Static height not considered for pump selection in closed loop. The design layout of a hyperbolic cooling tower is shown below. Like most other hvac equipment, the commissioning of cooling towers starts during design and continues on through construction, start. Institute of technology and research, gandhinagar, gujarat technological university, india abstract. Hyperbolic cooling tower repair structural technologies. General information above is an animation of a hyperbolic stacknatural draft cooling tower. Cooling tower efficiency calculations cooling tower approach. The disadvantages of a cooling tower are the cooling tower has to be registered with local authorities. At their closest, the sides of the tower are 40 meters apart. Pdf a survey on hyperbolic cooling towers semantic scholar.
Like other critical elements of the power generation process, disruption and downtime have to be minimized. The cooling system is housed in the tower s base which is typically the bottom 10 metres, the rest of the tower consisting of an empty shell. The fanlaws can be used topredi ctthe pe rformance ofa towerwitha nonstandard motor. As gravity draws the liquid downward, the updraft of cool air allows for evaporation and transfer of the heat from the fluid to the air, thereby lowering the temperature. A plume is formed in these towers which is a cloud of very small droplets 1. Cooling towers overcome most of these problems and therefore are commonly used to dissipate heat from watercooled refrigera tion, airconditioning, and industrial process systems. This water is circulated through the cooling tower as a oncethrough process, meaning that there is no aerosolisation or exposure of the cooling water to.
Modeling a cooling tower engineered software knowledge base. The at is the result of a decade of engineering success based on easy maintenance, durable construction and a highly efficient design. Traditional cooling towers are engineered to minimize the impact of dry off, but adiabatic systems are designed specifically to evaporate water completely to dry. 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. The water exits the cooling tower and is sent back to other units for further process conditions. Calcium carbonate scale will accumulate on the wetted surfaces of the adiabatic system just like it does where water evaporates completely to dry on any cooling tower. Range of cooling in f t1 t2 area wet bulb temperature in f twb the design heat load is determined by the flow rate, and the range of cooling, and is calculated using the following formula. There can be and actually are many different shapes of cooling towers. The hyperboloid shape is particularly suited to cooling tower construction as the wide base provides a large space for the water and cooling system. Optimization of the operating conditions for cooling tower. Ya abstractthe aim of the current study is to develop a numerical tool that is capable of achieving an optimum shape and design of hyperbolic cooling towers based on coupling a nonlinear finite. Air flows into the tower through openings in the bottom, and cools the entering hot water.
Natural draft cooling tower design and construction in germany past since 1965, present and future christian lang 1. We have decades of experience in cooling tower design, engineering, project management, and construction. Evaporators are the large things usually seen outside. Introduction to natural draft cooling towers amazon s3. The heat exchange surfaces are right in the lower part of the tower, producing current by buoyancy. The software program can be used for the analysis of existing towers or for the preparation of specifications for new towers. An indirect, or closed circuit cooling tower involves no direct contact of the air and the fluid, usually water or a glycol mixture, being cooled. The following design data is required to select cooling towers. In every application the target portion of the nozzle should be located at the correct distance above the top of the cooling tower fill to obtain maximum.
The present paper represents a complete collection of the studies done for cooling towers and would give an updated material for the researchers and design engineers in the field of hyperbolic. Pdf structural design aspects of hyperbolic cooling towers. According to them, the design of cooling tower is affected by tower characteristics and different types of losses generated in cooling tower. When there is a large pressure differential between the. To reduce the drift from cooling towers, drift eliminators are usually incorporated into the tower design to remove as many droplets as practical from the air stream before exiting the tower.
See the more detailed explanation of cooling towers systems, diagrams, pictures and principles below table of contents what is a cooling tower how do cooling towers work. Cooling tower performance calculations are usually performed numerically. Page 1 study on buckling behaviour of hyperbolic cooling towers ashok p ponath 1, manju george 2 department of civil engineering. Cooling towers are most commonly used to cool water in industries. Effect of wind loading on analysis of natural draught hyperbolic. Structural design aspects of hyperbolic cooling towers.
It is based on around fortyfive years of experience in the construction of cooling towers gained by plant and structural design engineers, by construction companies, checkup engi. Department of energy assistant secretary for resource. Cooling towers are designed and manufactured in several. The design layout of a cooling tower is shown in figure 11. Unlike the open cooling tower, the indirect cooling tower has two separate fluid circuits. Between the narrowest part and the top, there are 67. The purpose of a cooling tower is to keep a process from. Study on buckling behaviour of hyperbolic cooling towers. Understand the working principle and types of cooling towers. Cooling tower calculations software program is a powerful, user friendly, software program for the analysis of induced, mechanicaldraft, counterflow cooling towers. International journal of engineering trends and applications ijeta volume 3 issue 5, sepoct 2016 issn. The technical data is taken for mechanical draft cooling tower.
Artistic to scientific design of cooling towers the art of evaporative cooling is quite ancient, although it is only relatively recently that it has been studied scientifically. Solving applied problems involving hyperbolas college algebra. It is indicated that the value of mx and ty is sensitive to the initial geometrical imperfections, and the failure of shell in. Induced draft towers are typically mounted with a fan at the top of the cooling tower, which allows hot air out and pulls air throughout. Again, this will be a first issue releasing the actual engineering approach. The present paper is a detailed methodology for thermal design of cooling tower. So, in reality, natural draft cooling towers, also known as. Effective thermal design of cooling towers a stepbystep approach to cooling tower design, with an example calculation to make it clear jonny goyal air liquide engineering and construction, lurgi india various misconceptions arise when it comes to the thermal design of cooling towers. The cooling towers that are huge and seem like the chimneys to many folks are actually hyperbolic systems. Nov 22, 2014 after many years of cooling tower design and production, we want to share our experience with professionals in the field. These structures subjected to both self weight and environmental forces like earthquake force and wind force. Rp m 2 rp m 1 cfm 2 c fm 1 staticpressure 2 static pressure 1 cfm 2 cfm 12. These problems are associated with watercaused deposits. Design and inelastic behavior of hyperbolic cooling tower.
Natural draft cooling tower designs employ either crossflow or counterflow fill. The high exiting air velocities reduces the chance of re circulation. Natural draft cooling towers work by pumping the hot fluid upward into the tower. The theory of heat exchange in wet cooling towers is briefly summarized.
Cooling tower performance basic theory and practice subject. Nov 30, 2016 test your knowledge on cooling tower online quiz last updated november 30, 2016 cooling tower is an essential piece in most of the chemical process industries and in hvac applications. The pumping head determination procedure for the open tower piping loop differs from the conventional closed. Drift loss of the cooling tower is normally provided by the cooling tower manufacturer based on the process design. Commissioning cooling towers checklists for design, construction, and startup by davesellers, pe, senior engineer, portland energy conservation inc. Counterflow natural draft cooling tower fill arrangement. At their closest, the sides of the tower are 60 meters apart. Cooling tower bureau of energy efficiency 7 figure 7. Contrastive analysis is made on stress, internal force, displacement and failure probability of cooling tower shell. The hyperbolic shape itself does not help the cooling of a power plant. The design layout of a hyperbolic cooling tower is.