Vaporcompression refrigeration uses a circulating liquid refrigerant as the medium which absorbs and removes heat from the space to be cooled and subsequently rejects that heat elsewhere. The refrigerant is circulated through the system and it undergoes a no of changes in its state while passing through various components of the system. The most common refrigeration system in use today involves the input of work from a compressor and uses the vapor compression cycle. The vapour at low pressure and low temperature point 2 enters to compressor where it is compressed reversible. Brauna apurdue university department of mechanical engineering, 140 s. The heat required to evaporate water which flows on one side of a heat transfer surface is supplied through the simultaneous condensation of the distillateproducing vapor on. The system is quiet in operation due to less number of moving parts. Review of vapour absorption refrigeration and vapour. Vapour compression cycle definite guide with video.
Pdf in vapour compression refrigeration system, it generates fresh drinking water and also extracts water from humid ambient air by using. Refrigeration cycle is the basis of all refrigeration systems. Figure 1 depicts a typical vaporcompression system. A textbook of refrigeration and air conditioning simple vapour. Based on these analyses, we developed estimates for unit energy savings over baseline vaporcompression systems and identified relevant markets for each technology option e. In the vapor absorption process, the compression process of the vapor compression cycle is replaced by an absorber, a generator and a pump. According to the results of their experiments, the refrigerant r290r600a had a refrigerating capacity 28. At point 1, let t 1, p 1 and s 1 be the temperature, pressure and entropy of the vapour refrigerant. Two concepts which are normally integral to multipressure systems are, i. He attempted to export frozen meat to england on board the vessel norfolk in 1873 but failed and he was financially ruined. Holtzapple the ability to produce potable water economically is the primary purpose of seawater desalination research. Ueeneej103a establish the basic operating conditions of. Apparatus figure 1 shows the experimental setup in details.
As can be seen, the liquid leaving the condenser is cooled by passing through the throttle valve, where the pressure drops, resulting in partial vaporisation of the refrigerant and a significant reduction in temperature. Refrigerant r22 vapour enters a positive displacement compressor at a slightly. University of ontario institute of technology, oshawa, ontario. Air conditioners also employ a vaporcompression cycle to cool the ambient air temperature in a room.
It is also used in domestic and commercial refrigerators, largescale. At the bottom of the articles you can download pdf. A single stage vapour compression refrigeration system has one low side pressure. Vapour absorption system vapour absorption system is an attractive method for utilizing low grade energy directly for cooling.
Multistage vapour compression refrigeration systems nptel. All that is required to accomplish this is to modify the evaporator to accommodate the systems that are being cooled. Vapour compression systems are used for refrigeration and air conditioning. Pdf vapour compression refrigeration system generating fresh. Simple vapour compression refrigeration system with. He was successful in freezing meat in his refrigerator at a melbourne exhibition in 187273. Vaporcompression evaporation is the evaporation method by which a blower, compressor or jet ejector is used to compress, and thus, increase the pressure of the vapor produced. Ks01ej103a basic operating conditions of vapour compression systems evidence shall show an understanding of basic operating conditions of vapour compression systems, applying safe working practices and relevant standards, codes and regulations to an extent indicated by the following aspects.
While vaporcompression technologies have served heating, ventilation, and airconditioning hvac needs very effectively, and have been the dominant hvac technology for close to 100 years, the conventional refrigerants used in vaporcompression equipment contribute to global climate change when released to the atmosphere. Figure 1 shows a general simplified flow diagram of a basic mechanical vapor compression distillation system. Reductions in fossil fuel use and increases in system efficiency are required to make space heating more environmentally benign. Hrnjak, in 8th international conference on compressors and their systems, 20. Flow diagram of singleeffect vapor compression distillation system. Vapor compression refrigeration system basic, working, parts of system, advantages, and disadvantages introduction. The coefficient of performance of a refrigeration system is. Simple vapour compression system mechanical engineering. Vapour compression refrigeration cycle on ph diagram the ph diagram is frequently used in the analysis of vapour compression refrigeration cycle and usually consists of the four processes. It is also used in domestic and commercial refrigerators, largescale warehouses for chilled or frozen storage of foods and meats. Vaporcompression refrigeration, in which the refrigerant undergoes phase changes, is one of the many refrigeration cycles and is the most widely used method for airconditioning of buildings and automobiles. Key components in the refrigeration system are a compressor, a condenser, an evaporator and an expansion valve.
Vapor compression evaporators vces provide continuous evaporation by mechanically compressing the vapor produced by the system, and then feeding it back to the lamella package as the heating source. Gandhinagar institute of technology subject applied thermal and hydraulic engineering2140907 branch electrical topic refrigeration vapour compression refrigeration system 2. Vapor compression refrigeration system basic, working. Both a steadystate and a transient simulation will be considered. Typically, the compressed vapor is fed back to help heat the mother liquor in order to produce more vapor or steam. A multistage system is a refrigeration system with two or more lowside pressures. Performance of vapor compression systems with compressor oil flooding and regeneration i. Therefore, a combination of two compressors with low compression ratios can provide a high compression ratio. Each such change in the state of vapor is called a process. Compressor is said to the heart of the vapour compression system compresses the vapour refrigerant from the. Pharmaceutical vapor compression distillation vcd, improperly known as thermocompression or such as mechanical vapor recompression mvr or mechanical vapor compression mvc distillation, too, is the main way to produce wfi water for injection and grade waters for pharmaceutical use. In this article we will discuss about simple vapour compression refrigeration system.
Oil in circulation in an vapor compression refrigeration system is known to cause a reduction in heat transfer coefficient and increase in pressure drop in heat exchangers and connecting lines 1,2,3, as well as reducing the oil level inside the compressor crankcase. Eames1 1centre for sustainable technologies, school of the built enviroment, university of. The system is basically a heat exchanger that is an evaporatorcondenser. The vapor compression cycle can be used to cool air, liquid, or cold plates. Vapor absorption refrigeration cycle or vapor absorption refrigeration system vars pdf. The most commonly used method of cooling is with vaporcompression cycles, because it is fairly easy to construct a cooling device employing this method and the cost is low. In this system, two separate systems using different refrigerants. Since the pressure increase of the vapor also generates an increase in the condensation temperature, the same vapor can serve as the heating medium for its mother liquid or solution being concentrated, from which the. So refrigeration cycle should be known to understand the refrigeration system. Flownex was used to simulate a vapour compression refrigeration system using r22 as refrigerant. This is an important advantage as against the conventional vapour251compression system which operates on high grade energy. Analysis of a mechanical vapor compression desalination system.
Comparison of vapor absorption system with vapor compression system can be done in 9 aspects. Vapor compression distillation vc is a process used to produce water for injection wfi on the principle of distillation, where the water is distilled with phase change and entrainment separation. Lara and others published advanced mechanical vaporcompression desalination system find, read and cite all the research you need on researchgate. From 2 the high pressure high temperature vapour is first sensibly cooled to saturation, then condensed and ultimately sub. Their work presents a detailed exergy analysis of an actual vapour. Today we will study the difference between vapour compression and vapour absorption refrigeration system in detail. This case study demonstrates the modeling of a vapour compression refrigeration system using r22 as refrigerant. The above figure shows the objectives of refrigerators and heat pumps. Ppt vapour compression cycle powerpoint presentation. Performance analysis of vapour compression refrigeration system with r404a, r407c and r410a jyoti soni 1 and r c gupta corresponding author. Refrigeration cycles the vapor compression refrigeration cycle is a common method for transferring heat from a low temperature to a high temperature.
A vapor compression refrigeration system uses a refrigerant sealed in an airtight and leak proof mechanism. Before moving further on differences lets have an overview of both the vapour compression and vapour absorption refrigeration system. Advanced mechanical vaporcompression desalination system. Lecture16 simple vapour compression refrigeration system a vapour compression refrigeration system is an improved type of air refrigeration system in which a suitable working substance, termed as refrigerant is used. The principle of the system is to make use of two substances that can be separated when heated. Pdf comparative performance study of vapour compression. Vapor compression system an overview sciencedirect topics. To create an air cooling system, the evaporator acts as a refrigerant to an air heat exchanger. These all four components run a simple vapour compression refrigeration system. Thermodynamic performance evaluation of single stage. Multistage vapour compression refrigeration system eco. The purpose of a refrigerator is the removal of heat, called the cooling load, from a lowtemperature medium.
In the vc process, the vapor produced by evaporating the water is compressed to increase the saturation pressure and temperature. Pdf on mar 23, 2015, maqbool ur rehman and others published vapour compression cycle find, read and cite all the research you need on. A refrigeration system is a combination of components and equipment connected in a sequential order to produce the refrigeration effect. Martin jischke drive, west lafayette, in, 47906 abstract vapor compression refrigeration technology has seen great improvement over the last several decades in terms of. Mechanical vapor recompression mvr is an energy recovery process which can be used to recycle waste heat to improve efficiency. Vapor compression refrigeration cycle objective determining the coefficient of performance of a vapour compression refrigeration cycle. Design of two stage vapour compression refrigeration.
The encon mvc evaporator is a forced circulation flash evaporator utilizing mechanical vapor compression. For a closed cycle of refrigeration employing the condensable refrigerant vapour, the following processes are required. In fact, conventional refrigerators use this method of cooling to keep your leftovers and drinks chilled. Mechanical vapor compression distillation of saline water is a process in which mechanical energy is used as the main driving force. Vapour compression refrigera tion system, refrigerant, ozone depletion, global warming, cfc. Refrigerant r22 vapour enters a positive displacement compressor at a slightly superheated state 1 and is then compressed to state 2. Vapourcompression refrigeration or vaporcompression refrigeration system vcrs, in which the refrigerant undergoes phase changes, is one of the many refrigeration cycles and is the most widely used method for airconditioning of buildings and automobiles. This system was a dangerous system because of the flammability of the ether. The mechanical vapor compression mvc desalination system is based on distillation of seawater. Layout of the r22 vapourcompression refrigeration system. The refrigeration system were also used for providing cooling and humidification for summer comfort air conditioning 3. The system has more weak, tear and noise due to moving parts in the compressor.
Vapor compression distillation pharma vapor compressions. Vapor compression refrigeration cycle engineering essay. For temperatures in the range of 46oc to 101oc, cascaded systems are preferable. Energy analysis and comparison of advanced vapour compression heat pump arrangements stuart self 1, marc rosen 1, and bale reddy 1. Work is supplied to the compressor during the isentropic compression 12 of refrigerant vapour from evaporator pressure pe to condenser pressure pc, and work. Some basic refrigeration cycles are discussed here through different diagrams. As stated earlier, the system consists of an evaporatorcondenser, shown as heat transfer a.
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