R sekulib university of kentucky introduction a heat exchanger is a device that is used for transfer of thermal energy enthalpy between two or more fluids, between a solid surface and a fluid, or between solid particulates and a. Heat exchangers doehdbk1018193 heat exchanger applications figure 9 singlepass condenser there are different condenser designs, but the most common, at least in the large power generation facilities, is the straightthrough, single pass condenser illustrated figure 9. Design a single pass shell and tube type heat exchanger which requires. The compablocs unique plate design eliminates dead zones in the heat exchanger. However, in calculations of heat exchanger design, we. Optimal performance of a condenser is achieved with the proper design and selection of a wide array of auxiliary systems. Details of construction practices are described by saunders. But of the three, the counter flow heat exchanger design is the most efficient when comparing heat transfer rate per unit surface area. A heat exchanger with a single pass shell and multipass tube is defined as a 12 unit. Combining each of these resistances in series gives. Tlm however, in process engineering practice most heat exchangers are not of this type, having several shell passes and tube passes. Joule energy exerted by the force of one newton acting to. And large temperature glides have a greater influence than small ones.
The fourtubepass configuration for condensation is both. The optimum thermal design of a shell and tube heat exchanger involves the consideration of many interact. It is called a doublepipe exchanger because one fluid flows inside a pipe and the other fluid flows between that pipe and another pipe that surrounds the first. For a fixed tube sheet exchanger with removable channel. A simple exchanger, which involves one shell and one pass, is shown in. Crossflow, parallel flow, and counterflow heat exchanger configurations are three examples. To give a perspective, a human hair is about 75100 microns in diameter. In a single pass condenser, the cooling water makes one passage from end to end, through the tubes. As either single pass or two pass, depending on the number of parallel water flow paths through each shell. Single pass cms single pass standardized fixed tubesheet exchangers have been manufactured to the specifications displayed. Units can be provided in accordance with asme sect.
The actual design of heat exchangers is a complicated problem. Shellside film coefficient methods for single component condensation in turbulent flow. It has the advantage of low cost and simplicity of mechanical design, but its use is restricted to those applications in which mixing of the vapor and coolant is permissible. Shell and tube heat exchangers basic calculations instructor. Multiple shell and tube heat exchangers in the series are employed to handle the temperature cross in the chemical process industries. Shelland tube heat exchangers provide typically the surface area density ranging from 50 to 500 m 2m 3 and are easily cleaned.
The configuration of the exhaust flow pattern entering the condenser. There can be many variations on the shell and tube design. Pdf design of multiple shell and tube heat exchangers in. The cooling water flows once through the condenser and is termed a single pass. Steam turbine condensers in power plants are often 1 pass straighttube heat exchangers. Introduction a condenser is a type of heat exchanger in which vapors are transferred into liquid state by removing the latent heat with the help of a coolant such as water. This portable document format \ pdf \ file contains bookmarks, thumbnails, and hyperlinks to help you navigate through the document. The design codes and standards are available in the tema 1999tubular exchanger manufacturers association. We define the evaporation process as one that starts with a liquid. Heat transfer by heat exchangers tema design piping. Evaporation is an operation used to remove a liquid from a solution, suspension, or emulsion by boiling off some of the liquid. The number of passes on the hot and cold side can be chosen independently, making it possible to optimize heat transfer even if flow rates on the different sides.
Hvac design for cleanroom facilities ced engineering. As the refrigerant passes through the condenser, its. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Figure 9 single pass condenser 15 figure 10 jet pump 16. In intercoolers, boilers, preheaters and condensers inside power plants as well as other engineering processes, heat exchangers are utilized for controlling heat energy. Since the water flow rate for winter operation may be less than the summer flow rate, it can be concentrated in fewer cells, which allows the flow rate per cell to remain high.
Lmtd is restricted to the single pass parallel and counter. This condenser design gives cooling water flow by straight tubes from the inlet water box on one end, to the outlet water box on. Selection of heat exchanger tema layout and number of passes. Heat exchangers 73 individual thermal resistances of the system. Ctp is the tube count calculation constant and cl is the tube layout constant. Basic design methods of heat exchanger, heat exchangers design, experiment and simulation, s m sohel murshed and manuel matos lopes, intechopen, doi. Ideal condenser with single component refrigerant in pure counterflow the illustration in figure 5 uses the temperatures of the condenser in the example shown in. The two flows in a compabloc can be configured as single pass, or as multiple pass by using baffles. Singlepass condensers, large steam system condensers. Large steam system condensers heat exchanger engineers. Steam surface condenser design based on cost optimization using genetic algorithm. For a single pass counterflow heat exchanger the design value ua follows from ua q.
A counterflow heat exchanger will require less heat exchange surface area than a parallel flow heat exchanger for the same heat transfer rate and the same inlet and outlet temperatures for the fluids. Comparison of heat exchanger types each of the three types of heat exchangers parallel, cross and counter flow has advantages and disadvantages. Experimental and numerical model for thermal design of air cooled condenser. The doublepipe heat exchanger is one of the simplest types of heat exchangers. The optimum thermal design of a shell and tube heat exchanger involves the consideration of many interacting design. This chapter discusses the basic design methods for two fluid heat exchangers. One shell pass and any multiple of two tube passes. In a single pass heat exchanger, the fluid goes in one end of each tube and out the other. For condensation in the tube side by taking one half of the conventional pressure drop relation can be used. Design and analysis of a 5mw verticalflutedtube condenser for. This condenser design provides cooling water flow through straight tubes from the inlet water box on one end, to the. An introduction to condensers and auxiliary equipment for. Two exchangers in series can be modeled in one shell. Shell and tube heat exchangers basic calculations pdh online.
There are various condenser designs, but the most general, at least in the large power generation facilities, is the straightby, singlepass condenser described in above figure. Single pass condensers have an inlet water box on one end and an outlet water box on the other end. Two pass condensers have the cooling water inlet and. Depending on the degree of temperature cross, certain number. Steam surface condensers water cooled maarky power. This condenser design provides cooling water flow through straight tubes from the inlet water box on one end, to the outlet water box on the other end. Important parameters for baffle design are its cut percentage of shell.
Mathematical models of aircooled condensers for thermoelectric units. The size of contaminants and particles are usually described in microns. Shell and tube heat exchanger design there can be many variations on the shell and tube design. The directcontact condenser is one in which the coolant is brought into contact with the vapor. Heat exchangers are devices that regulate efficient heat transfer from one fluid to another. For an evaporator or condenser, c0, because if one fluid remains at a constant temperature. Good practice for heat exchanger selection and design page 4 of 12 use one tube pass per shell pure counter current. Effective steam condenser design, of necessity, must take many performance variables into consideration. Tube side pressure drop in case of tube side condensation. Heat exchangers jordan university of science and technology. Gbhepeghea508 selection and design of condensers information contained in this publication or as otherwise supplied to users is believed to be accurate and correct at time of going to press, and is given in good faith, but it is for the user to satisfy itself of the suitability of the information for its. E1mnl032a design and rating of shell and tube heat. Ix of the boiler and pressure vessel code, tema, api, hei, and 3 a standards.
Experimental and numerical model for thermal design of air. It is thus a thermal separation, or thermal concentration, process. One objective in the design of this exchanger is to obtain the highest allowable. Each condenser is designed in accordance with the clients specifications to offer the highest thermal efficiency and structural integrity. Good practice for heat exchanger selection and design. Tema g and h shell designs are most suitable for phase change applications where the bypass around the longitudinal plate and countercurrent flow is less important than even flow.
Pdf heat exchanger types and classifications researchgate. A heat exchanger can have several different flow patterns. Two and four pass designs are common because the fluid can enter and exit on the same side. Heat exchangers heat exchangers are used to transfer heat between two sources. Typical arrangement of steam turbine condenser large power plant condensers are usually shell and tube heat these types of condensers are also classified. The model is validated through comparison with theoretical algebraic relations for single pass. Design and analysis of water cooled condenser sanjana v. For these designs a correction factor f is applied, using. Provides for single and multiple tube passes to assure proper velocity. Steam surface condenser design based on cost optimization.
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