Thermodynamicsbased optimization and control of vaporcompression cycle operation. Enhancement of cop of vapour compression refrigeration system. Gascycle refrigeration, is essentially, a reversed joule cycle gas turbine cycle. Page 5 of practical vapour compression refrigeration cycle in practice the reverse carnot cycle is adjusted to the vapour compression refrigeration cycle shown below in figure 3. The working fluid is a refrigerant that suits the high and low temperature reservoirs temperatures. Please take a moment to comment on the effectiveness of this air conditioning clinic. Working principle of vapour compression refrigeration system, overview of vaporcompression refrigeration cycle, major components and heatwork transfers, comparison with. In gas cycles, heat rejection and refrigeration take place as the gas undergoes sensible cooling and heating. A slight performance improvement in the components of a vapor. The vapour compression refrigeration system is by far the most popular and widely used system in refrigeration and air conditioning bot for industrial and domestic applications. Multistage vapour compression refrigeration systems nptel. Based on these analyses, we developed estimates for unit energy savings over baseline vaporcompression systems and identified relevant markets for each technology option e.
Multistage vapour compression refrigeration example1 two stage compression system with water intercooler uses r4a as shown in figure1. Vapor compression refrigeration system basic, working. Figure 56 shows the increase in refrigeration capacity area under 47 and decrease in compressor work 2265. However, unlike water the refrigerant has a much lower boiling point. It also includes the process of maintaining and reducing the temperature of a body below the general temperature of its surroundings.
In a vaporcompression refrigeration system i would like to understand the following. Each such change in the state of vapor is called a process. In a vapour cycle the working fluid undergoes phase. Vapor compression refrigeration hvacr heat pumps air. Cant the saturated vapor from the evaporator be cooled directly in the condenser. The evaporating temperature is 25 oc and condensing temperature 47 oc. The system, as shown in figure 7, is basically the same as that of the vaporcompression cycle. Each stage operates on an ideal vaporcompression refrigeration cycle. Based on these analyses, we developed estimates for unit energy savings over baseline vapor compression systems and identified relevant markets for each technology option e. Vapour compression systems are used for refrigeration and air conditioning.
In many hvac air conditioner and heat pump applications, the process of refrigeration or the vaporcompression cycle is what makes it work. Refrigeration and air conditioning systems onboard ships. 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. Vapour compression refrigeration system slideshare. A refrigeration tutor is mainly use for academic purpose because of its simplicity in operation.
The refrigerant is let into and measured by a flow control device, and eventually released to the compressor. Malwe refrigerator, which is so common and runs continuously everywhere. Exergy analysis of vapour compression refrigeration system. Performance analysis of vapour compression refrigeration. Vapor compression refrigeration cycle engineering essay. Refrigeration vcr system with different refrigerants. Zheng and meng 2012 have studied the thermodynamic mechanism of hybrid cycle and they plotted a graph for compression. This work provides an economic comparison between a vapor compression refrigeration system powered by a photovoltaic array and a vapor absorption refrigeration system powered by a. Air conditioning clinic refrigeration system components. Fluid retrofit for existing vapor compression refrigeration systems.
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. New regenerative cycle for vapor compression refrigeration osti. Pdf vapour compression refrigeration system generating. Mechanical subcooling provides a better performance as compared to conventional air cooled refrigeration system upto 22% improvement in. 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. Refrigerant, compressor, expansion valve flow control device, evaporator. Twostage compression cycle with one evaporator and intercooling with flash gas 53.
How an expansion valve works exactly physically speaking. Why does it need to be a superheated vapor in order to be condensed. Vapourcompression refrigeration or vaporcompression refrigeration system vcrs, in which the refrigerant undergoes phase changes, is one of the many. Et 411c compression refrigeration system gunt hamburg.
Vapor compression refrigeration system basic, working, parts of system, advantages, and disadvantages introduction. Both a steadystate and a transient simulation will be considered. Identify possible compression concepts for use in miniature. 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.
The vaporcompression refrigeration is the most widely used cycle for refrigerators, air conditioners, and heat pumps. Optimization criteria neera jain, student member, ieee, andrew g. It is also used in domestic and commercial refrigerators, largescale. Chapter 10 refrigeration cycles 103 ideal and actual vaporcompression cycles 104c yes. This course is an overview of vapor compression refrigeration cycle, principles of heat generation, transfer and rejection. Modeling and investigation of refrigeration system performance with twophase fluid injection in a scroll compressor rui gu marquette university, 2016 vapor compression cycles are widely used in heating, refrigerating and airconditioning. Because its function is to absorb heat into the refrigeration system from where you dont want it, the evaporator is placed in the area to be cooled. Design and simulation of a vapor compression refrigeration cycle for a micro refrigerator submitted by seyfettin yildiz in partial fulfillment of the requirements for the degree of master of science in mechanical engineering department, middle east technical university by, prof. Development of a miniature vapor compression refrigeration. Refrigeration system components level of detail circle one too basic just right too difficult one of the fundamental series rate this clinic from 1needs improvement to 10excellent trgtrc005en content 123456789 10 booklet usefulness 123456789 10. Schematic diagram of a simple vapor compression refrigeration system is shown in fig. Refrigeration systems and applications, second edition. System description the layout of the system is shown in figure 1. The process of refrigeration uses the vaporcompression refrigeration cycle to move heat from one place to another.
A refrigeration system allows transfer of heat from a cooling chamber to a location where the heat can be easily discarded. A vaporcompression refrigeration system with a capacity of 10 tons has refrigerant 4a as the working fluid. Vapour compression refrigeration system generating fresh water from humidity in the air conference paper pdf available january 2011 with 4,283 reads how we measure reads. The refrigeration capacity is 8 tr and the compression is.
Layout of the r22 vapour compression refrigeration system. In this system, the working substance is a refrigerant like nh 3, r11, r12. Layout of the r22 vapourcompression refrigeration system. Evaluation of vapour compression refrigeration system. The transfer of heat is accomplished by using a refrigerant, which can change its state from liquid to gas. Chapter 10 refrigeration cycles ideal and actual vapor. A vaporcompression refrigeration system and a phasechange heat pump seem to be the same thing. As the name indicates, the refrigerant in these systems is a gas.
Vapor compression system an overview sciencedirect topics. Here harshit solves some sample questions which will help one to recollect and remember all the topics and equations which were discussed in the previous lesson. The proposed vapor compression cycle vcc reduces the instability of flow in microgravity through both reduction on liquid reliance via a coupled oilfree scroll. Request pdf development of a miniature vapor compression refrigeration system for electronic cooling computer chips have generally been cooled by means of. Working principle, types and comparison with vapor compression system, saving potential 4. The most common refrigeration system in use today involves the input of work from a compressor and uses the vapor compression cycle. The model developed helps in design of such systems. The setup of et 411c represents a typical refrigeration circuit consisting of a hermetic compressor, condenser, evaporator and expansion element.
The vapour compression cycle which is used in vapour compression refrigeration system is nowadays used for all purpose refrigeration. The vapor compression refrigeration cycle is a common method for transferring heat from a low temperature to a high temperature. Performance analysis of vapour compression refrigeration system. Performance analysis of vapour compression refrigeration system with r404a, r407c and r410a jyoti soni 1 and r c gupta corresponding author.
It is also used in domestic and commercial refrigerators, largescale warehouses for chilled or frozen storage of foods and meats. The first component in the process is a compressor or the heart of an air conditioner or heat pump system. Thermodynamicsbased optimization and control of vapor. This case study demonstrates the modeling of a vapour compression refrigeration system using r22 as refrigerant. This is the part of the refrigeration system that is doing the actual cooling. The most commonly used system for industrial and commercial refrigeration is the vapour.
In this type of system, the refrigerant flows through a closed cycle in the following four states. Effect of evaporator temperature on cycle performance ph diagram. A miniature vapor compression system could be used in any high power density electronics application, including workstations and servers. A twostage refrigeration cycle consider a twostage cascade refrigeration system operating between pressure limits of 0. Refrigeration may be defined as a process of removing heat from a substance and pumping it to the surroundings. The aim of this work is to investigate the performance analysis of vapor. There are innumerable applications of such systems and they are. A vapor compression refrigeration system uses a refrigerant sealed in an airtight and leak proof mechanism.
Vapor compression 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. Comparison of vapor absorption system with vapor compression system can be done in 9 aspects, they are energy input, moving part, evaporator pressure, load variation, evaporator exit, coefficient of performance, capacity, refrigerant and lowest temperatures. It is used for all industrial purposes from a small domestic refrigerator to a big air conditioning plant. The performance of refrigeration plant is expressed as coefficient of performance cop which is defined as the ratio of refrigerating effect produced to the work of compression. In this lesson, one will learn how to solve the problems on vapour compression cycle. The compressor hvac refrigeration in a typical hvac air conditioner or heat pump, there are four major components that make the process of refrigeration work. R290 and r600a offer many desirable characteristics such. 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. 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. Heat pumps are devices that operate in a cycle similar to the vaporcompression refrigerator cycle illustrated in figure 1 in its most basic form, a vaporcompression refrigeration system see van wylen 1985 consists of an evaporator, a compressor, a condenser, a throttling device which is usually an expansion valve or capillary tube and the connecting tubing. Twostage compression cycle with one evaporator and intercooler with water 51. Refrigeration and air conditioning systems onboard ships vapour compression systems moving heat from a lower temperature to higher temperature requires work to be done, according to second law of thermodynamics and this work can be done in many ways in different systems. Exergy analysis it includes exergy analysis of refrigeration tutor. Information and data for the cycle are provided in fig.
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