The vapor compression cycle circulates a fluid through a compressor, condenser, expansion valve, and evaporator, in order to absorb heat from a refrigerated space at a low temperature and give off heat at a higher temperature to the surroundings, thus keeping the refrigerated space cool. Before we dive in, lets get an understanding of four key concepts. Pdf exergy analysis of vapour compression refrigeration. Representation of vapour compression refrigeration. Before moving further on differences lets have an overview of both the vapour compression. Both a steadystate and a transient simulation will be considered.
Ppt vapour compression cycle powerpoint presentation. Jun 01, 2017 rac hindi l 03 vapour compression refrigeration cycle by mr vikash kumar duration. Refrigeration cycles the vapor compression refrigeration cycle is a common method for transferring heat from a low temperature to a high temperature. Vapor compression refrigeration systems are used for a variety of coolingrefrigeration applications. The vapor compression refrigeration cycle is a common method for transferring heat from a low temperature to a.
The rankine cycle is the ideal cycle for vapor power plants. The points which are required for engineering calculation are from h 1 to h. Compression refrigeration cycle the vaporcompression refrigeration is the most widely used cycle for. This is an important advantage as against the conventional vapour251compression system which operates on high grade energy. This course is an overview of vaporcompression refrigeration cycle, principles of heat generation, transfer and rejection. By araner posted 20180223 in refrigeration the vapor compression refrigeration cycle is nearly 200 years old, but it does not seem ready to leave the scene any time soon. Twostage compression cycle with one evaporator and intercoolerflash tank 55. Sep 10, 2016 the refrigeration cycle is a critical component of hvac systems and is governed by the principles of thermodynamics. The schematic sketch of doubleeffect system is shown in fig. Layout of the r22 vapourcompression refrigeration system. While some people have viewed this method as environmentally harmful and inecient, the cycle is still applicable in the industrial sp. However, for large industrial applications efficiency, not simplicity, is the major.
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. Chapter 10 examples solution 1 an ideal vaporcompression refrigerant cycle operates at steady state with refrigerant 4a as the working fluid. The coefficient of performance of a refrigeration system is. The above figure shows the objectives of refrigerators and heat pumps. Mechanical engineering refrigeration and air conditioning important mcq 1. Which device is used for the expansion of refrigerant in vapour compression refrigeration cycle. Heat rejection from the lower cycle to the upper cycle takes place in an. This is often measured at the liquids boiling point. Compressor is said to the heart of the vapour compression system compresses the vapour refrigerant from the. Though the air is heated and cooled in the air conditioning unit it is the refrigeration cycle using r12 refrigerant as the working fluid which is the main focus of the experiment. 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.
So refrigeration cycle should be known to understand the refrigeration system. Isentropic compression water enters the pump as state 1 as saturated liquid and is compressed isentropically to the operating pressure of the boiler. Vocabulary background in the thermodynamics and refrigeration literature, several words are used interchangeably that can cause confusion. Analysis of a vaporcompression refrigeration cycle maplesoft. The refrigerant absorbs heat from one place and releases it to another place. The vapour compression cycle which is used in vapour compression refrigeration system is nowadays used for all purpose refrigeration. The standard vapor compression refrigeration system is a condenser, evaporator, throttling valve, and a compressor. The vapor compression refrigeration cycle is a common method for transferring heat from a low temperature to a high temperature. Some basic refrigeration cycles are discussed here through different diagrams. Page 4 of 4 theory of vapour compression refrigeration cycles carnot cycle this experiment uses a vapour compression refrigeration cycle which cools air down. Mechanical engineering refrigeration and air conditioning. Vapour absorption system vapour absorption system is an attractive method for utilizing low grade energy directly for cooling. Vapour compression 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.
A comparative study has been carried out of r12, 22, 125, 4a, 152a, 218, 245, 500, 502, 507 and 717 as working fluids in a vapour compression refrigeration system. Mechanical refrigeration works by changing the the majority of heat is removed from the the majority of the works by removedchanging the absorbed heat is state of the refrigerant. A heat pump uses a vapour compression cycle with refrigerant 12. Each of the four stages will now be revisited in detail, explaining the physical changes that occur in the refrigerant and the devices used to accomplish these changes. Deviation of actual vapor power cycle from ideal cycle as a result of irreversibilities in various components such as fluid friction and heat loss to the surroundings, the actual cycle deviates from the ideal rankine cycle. To improve the coefficient of performance cop, it is require decreasing the compressor work and increasing the refrigerating effect. Layout of the r22 vapour compression refrigeration system. Vapor compression refrigeration system basic, working, parts of system, advantages, and disadvantages introduction. The vapor compression refrigeration cycle is nearly 200 years old, but it does not seem ready to leave the scene any time soon. The ordinary vaporcompression refrigeration systems are simple, inexpensive, reliable, and practically maintenancefree.
Development of vapour compression refrigeration cycle a k bajpai 1 and vivek dwivedi 2 it will be possible only if heat is transferred from the low temperature region to a high temperature region. Refrigeration cycle is the basis of all refrigeration systems. The vaporcompression uses a circulating liquid refrigerant as the medium usually r4a which absorbs and removes heat from the space to be cooled and. The operation of the absorption refrigeration cycle is similar to the above vapour compression cycle. Review of vapour absorption refrigeration and vapour. In this cycle, the refrigerant is sealed condition in an airtight mechanism is compressed in a compressor which permits the transfer of heat energy. Vapor compression refrigeration system basic, working. A simple and practical absorption system using ammonia as refrigerant and water as absorbent described in the previous articles is an example of singleeffect cycle system for vapour absorption refrigeration system. A comparative study has been carried out of r12, 22, 125, 4a, 152a, 218, 245, 500, 502, 507 and 717 as working fluids in a vapourcompression refrigeration system. Saturated vapor enters the compressor at 100c, and saturated liquid leaves the condenser at 280c. The compressor is driven by a heat engine with a thermal efficiency of 40%. This case study demonstrates the modeling of a vapour compression refrigeration system using r22 as refrigerant.
Obviously it is not possible in the natural manner because heat flows from high. Pdf exergy analysis of vapour compression refrigeration system. At the bottom of the articles you can download pdf. Today we will study the difference between vapour compression and vapour absorption refrigeration system in detail. A refrigerant design problem for a vaporcompression refrigeration cycle was presented previously gani et al. In this paper, the case study was extended to include an expanded search space, inclusion of utility streams and practical design criteria. This amounts to 40% of the energy supplied in the fuel. The refrigeration cycle is a critical component of hvac systems and is governed by the principles of thermodynamics. Refrigeration and air conditioning pdf book agrimoon. It is also used in domestic and commercial refrigerators, largescale warehouses for chilled or frozen storage of foods and meats. What is vaporcompression cycle refrigeration cycle. A textbook of refrigeration and air conditioning simple vapour. The evaporator, condenser, and expansion device serve common purposes, but a heatoperated absorber and regenerator replace the compressor.
Th movement cooling by the removal of heat the movement of heat from a place where it is notot a ted to a wanted to a. Vcr uses mechanical energy as the driving force for refrigeration, while var uses thermal energy as the driving force for refrigeration. This cogitation is to base on idea simple cycle with no losses. System description the layout of the system is shown in figure 1.
Pdf vapour compression refrigeration shubham maurya. 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. It is a compression process, whose aim is to raise the refrigerant pressure, as it flows from an evaporator. Vapour absorption refrigeration system with diagram. The refrigeration system were also used for providing cooling and humidification for summer comfort air conditioning 3. Comparing the absorption refrigeration cycle with the more familiar vapor compression refrigeration cycle is often an easy way to introduce it. The highpressure refrigerant flows through a condenserheat exchanger before attaining the initial. The investigations shows that various results are obtained for the effect of evaporating temperatures, condensing temperatures, degree of subcooling and effectiveness of liquidvapour heat exchanger on cop, exergetic efficiency and edr of theoretical vapour compression refrigeration cycle. The design problem concerns the replacement of r4a refrigerant. The vapor compression refrigeration cycle, step by step. The vapor compression refrigeration cycle, step by step araner. The most common refrigeration system in use today involves the input of work from a compressor and uses the vapor compression cycle. Each stage operates on an ideal vapor compression refrigeration cycle with refrigerant4a as the working fluid.
The primary difference is in the manner in which heat is utilized. Figure 15 refrigeration cycle on the ph diagram take the structure image of this refrigeration cycle from figure 15, it becomes the ph diagram for engineering calculation as shown in figure 16. The vaporcompression uses a circulating liquid refrigerant as the medium usually r4a which absorbs and removes heat from the space to be cooled and subsequently rejects that heat elsewhere. Actual vapour power cycle in hindi lecture5 duration. Vapour compression refrigeration cycle mcqs with answers. A unit that is not specifically listed in a publicly available sales brochure, magazine advertisement, website posting or catalog selection rating application. Performance cop of refrigeration cycle is developed.
Vapourcompression refrigeration or vaporcompression refrigeration system vcrs, in which. Before moving further on differences lets have an overview of both the vapour compression and vapour absorption refrigeration system. It is also used in domestic and commercial refrigerators, largescale warehouses for. The vapour compression refrigeration and vapour absorption refrigeration systems were developed around 1870. This is the amount of heat required to turn a liquid into a gas. Vapour compression refrigeration cycle mcqs with answers q1. Absorption refrigeration an overview sciencedirect topics. While some people have viewed this method as environmentally harmful and inefficient, the cycle is still applicable in the industrial sphere. Ppt vapour compression cycle powerpoint presentation free.
Vapour compression cycle refrigeration atmospheric. Vapour compression cycle definite guide with video. Case1 the basics of refrigeration cycle ph diagram analysis. Consider a twostage cascade refrigeration system operating between the pressure limits of 0. It is also used in domestic and commercial refrigerators, largescale. Twostage compression cycle with one evaporator and intercooler with water 51. The vapor compression refrigeration cycle involves four components.
The deviations of actual pumps and turbines from the isentropic ones can be accounted for by utilizing. Compressor basic refrigeration cycle evaporator condenser receiver expansion device. It is a machine specifically designed to make use of a vapor compression refrigeration cycle to transfer heat from a cold water fluid circulating system to the air. It readily evaporates and condenses or changes alternatively between the vapor and liquid phase without leaving the refrigerating plant. Difference between vapour compression and vapour absorption pdf.
Experimental analysis on vapour compression refrigeration vcr system with r4a tetra fluro ethane refrigerant. Natural gas plants, petroleum refineries, and petrochemical plan. Vaporcompression cycle refrigeration cycle vaporcompression cycle thermodynamic cycle of heat pumps. Most of industrial process uses a lot of thermal energy by burning fossil fuel to produce steam or heat for the purpose. Additionally, a pht chart with the refrigeration cycle will be plotted. Vapor compression refrigeration an overview sciencedirect. The vaporcompression refrigeration is the most widely used cycle for refrigerators, air conditioners, and heat pumps. This is a pdf on the basic vapour compression cycle. Twostage compression cycle with one evaporator and intercooling with flash gas 53. Refrigeration may be defined as a process of removing heat from a substance and pumping it to the surroundings. Vapour compression cycle generally known as vcc is a refrigeration cycle. Rac hindi l 03 vapour compression refrigeration cycle by mr vikash kumar duration. First, evaporation is simply the process of vaporization these two terms are essentially synonymous. Refrigeration vcr and vapour absorption refrigeration var.
Aug 30, 2019 vapor compression refrigeration cycle. Basic refrigeration cycle and concepts, standard rating of refrigerating machines. Compression refrigeration cycle the vaporcompression refrigeration is the most widely used cycle for refrigerators, airconditioners, and heat pumps. Heat removed from the engine in the cooling system is recovered. Vapour compression cycle free download as powerpoint presentation. It also includes the process of maintaining and reducing the temperature of a body below the general temperature of its surroundings. The compressor, condenser, throttle and evaporator are analyzed separately from each other. The heat pump cycle uses an ideal cycle with an evaporator at 5oc and a condenser. Exergy analysis of vapour compression refrigeration system article pdf available in international journal of applied engineering research 412. Download pdf lectures on vapour absorption refrigeration system what is vapour absorption refrigeration cycle.
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