The vaporcompression uses a circulating liquid refrigerant as the medium usually r4a which absorbs and removes heat from the space to be cooled and. Refrigeration may be defined as a process of removing heat from a substance and pumping it to the surroundings. This cogitation is to base on idea simple cycle with no losses. A unit that is not specifically listed in a publicly available sales brochure, magazine advertisement, website posting or catalog selection rating application. The operation of the absorption refrigeration cycle is similar to the above vapour compression cycle. What is vaporcompression cycle refrigeration cycle.
This is often measured at the liquids boiling point. Mechanical engineering refrigeration and air conditioning. Pdf exergy analysis of vapour compression refrigeration system. Vapour compression cycle refrigeration atmospheric. The rankine cycle is the ideal cycle for vapor power plants. Compression refrigeration cycle the vaporcompression refrigeration is the most widely used cycle for refrigerators, airconditioners, and heat pumps.
A heat pump uses a vapour compression cycle with refrigerant 12. 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. The refrigerant absorbs heat from one place and releases it to another place. The heat pump cycle uses an ideal cycle with an evaporator at 5oc and a condenser. Performance cop of refrigeration cycle is developed. Vapourcompression refrigeration or vaporcompression refrigeration system vcrs, in which. The coefficient of performance of a refrigeration system is. 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. Difference between vapour compression and vapour absorption pdf. The highpressure refrigerant flows through a condenserheat exchanger before attaining the initial. This is the amount of heat required to turn a liquid into a gas. Vaporcompression cycle refrigeration cycle vaporcompression cycle thermodynamic cycle of heat pumps. The standard vapor compression refrigeration system is a condenser, evaporator, throttling valve, and a compressor.
Chapter 10 examples solution 1 an ideal vaporcompression refrigerant cycle operates at steady state with refrigerant 4a as the working fluid. Pdf vapour compression refrigeration shubham maurya. Page 4 of 4 theory of vapour compression refrigeration cycles carnot cycle this experiment uses a vapour compression refrigeration cycle which cools air down. The vapor compression refrigeration cycle, step by step araner. Ppt vapour compression cycle powerpoint presentation. It readily evaporates and condenses or changes alternatively between the vapor and liquid phase without leaving the refrigerating plant. Compression refrigeration cycle the vaporcompression refrigeration is the most widely used cycle for. The vapor compression refrigeration cycle is a common method for transferring heat from a low temperature to a. 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.
Isentropic compression water enters the pump as state 1 as saturated liquid and is compressed isentropically to the operating pressure of the boiler. 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. Twostage compression cycle with one evaporator and intercoolerflash tank 55. Most of industrial process uses a lot of thermal energy by burning fossil fuel to produce steam or heat for the purpose. Natural gas plants, petroleum refineries, and petrochemical plan. Consider a twostage cascade refrigeration system operating between the pressure limits of 0. Refrigeration cycles the vapor compression refrigeration cycle is a common method for transferring heat from a low temperature to a high temperature. 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. This is a pdf on the basic vapour compression cycle. Vapour compression cycle definite guide with video. Analysis of a vaporcompression refrigeration cycle maplesoft. Both a steadystate and a transient simulation will be considered.
Before moving further on differences lets have an overview of both the vapour compression. Actual vapour power cycle in hindi lecture5 duration. The refrigeration cycle is a critical component of hvac systems and is governed by the principles of thermodynamics. The deviations of actual pumps and turbines from the isentropic ones can be accounted for by utilizing. 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. Vapour compression refrigeration cycle mcqs with answers q1. Pdf exergy analysis of vapour compression refrigeration.
The vapor compression refrigeration cycle is a common method for transferring heat from a low temperature to a high temperature. In this cycle, the refrigerant is sealed condition in an airtight mechanism is compressed in a compressor which permits the transfer of heat energy. 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. Twostage compression cycle with one evaporator and intercooler with water 51. Compressor basic refrigeration cycle evaporator condenser receiver expansion device.
Sep 10, 2016 the refrigeration cycle is a critical component of hvac systems and is governed by the principles of thermodynamics. The vaporcompression refrigeration is the most widely used cycle for refrigerators, air conditioners, and heat pumps. It is a compression process, whose aim is to raise the refrigerant pressure, as it flows from an evaporator. Vapour compression cycle free download as powerpoint presentation. 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. Comparing the absorption refrigeration cycle with the more familiar vapor compression refrigeration cycle is often an easy way to introduce it. Some basic refrigeration cycles are discussed here through different diagrams. Layout of the r22 vapourcompression refrigeration system. 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.
The design problem concerns the replacement of r4a refrigerant. While some people have viewed this method as environmentally harmful and inecient, the cycle is still applicable in the industrial sp. Heat rejection from the lower cycle to the upper cycle takes place in an. Experimental analysis on vapour compression refrigeration vcr system with r4a tetra fluro ethane refrigerant. Vapour compression refrigeration cycle mcqs with answers. The compressor is driven by a heat engine with a thermal efficiency of 40%. Before we dive in, lets get an understanding of four key concepts. However, for large industrial applications efficiency, not simplicity, is the major.
This course is an overview of vaporcompression refrigeration cycle, principles of heat generation, transfer and rejection. Obviously it is not possible in the natural manner because heat flows from high. Review of vapour absorption refrigeration and vapour. Refrigeration vcr and vapour absorption refrigeration var. The above figure shows the objectives of refrigerators and heat pumps. The primary difference is in the manner in which heat is utilized. The schematic sketch of doubleeffect system is shown in fig.
Vapor compression refrigeration system basic, working, parts of system, advantages, and disadvantages introduction. To improve the coefficient of performance cop, it is require decreasing the compressor work and increasing the refrigerating effect. The evaporator, condenser, and expansion device serve common purposes, but a heatoperated absorber and regenerator replace the compressor. The compressor, condenser, throttle and evaporator are analyzed separately from each other. While some people have viewed this method as environmentally harmful and inefficient, the cycle is still applicable in the industrial sphere. Rac hindi l 03 vapour compression refrigeration cycle by mr vikash kumar duration. Compressor is said to the heart of the vapour compression system compresses the vapour refrigerant from the. Refrigeration cycle is the basis of all refrigeration systems.
Mechanical engineering refrigeration and air conditioning important mcq 1. Vapour absorption refrigeration system with diagram. Saturated vapor enters the compressor at 100c, and saturated liquid leaves the condenser at 280c. Vapor compression refrigeration an overview sciencedirect. This is an important advantage as against the conventional vapour251compression system which operates on high grade energy. The vapour compression refrigeration and vapour absorption refrigeration systems were developed around 1870. 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. 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. So refrigeration cycle should be known to understand the refrigeration system. The vapor compression refrigeration cycle, step by step. Vapor compression refrigeration systems are used for a variety of coolingrefrigeration applications.
Vocabulary background in the thermodynamics and refrigeration literature, several words are used interchangeably that can cause confusion. Additionally, a pht chart with the refrigeration cycle will be plotted. This case study demonstrates the modeling of a vapour compression refrigeration system using r22 as refrigerant. Aug 30, 2019 vapor compression refrigeration cycle. 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. Exergy analysis of vapour compression refrigeration system article pdf available in international journal of applied engineering research 412. The vapor compression refrigeration cycle is nearly 200 years old, but it does not seem ready to leave the scene any time soon. Vapour absorption system vapour absorption system is an attractive method for utilizing low grade energy directly for cooling.
A refrigerant should have a tow specific heat of liquid b high boiling point c high latent heat of vaporisation d higher critical temperature e low specific volume of vapour. The ordinary vaporcompression refrigeration systems are simple, inexpensive, reliable, and practically maintenancefree. The vapor compression refrigeration cycle involves four components. Refrigeration and air conditioning pdf book agrimoon. A textbook of refrigeration and air conditioning simple vapour. It also includes the process of maintaining and reducing the temperature of a body below the general temperature of its surroundings. 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. Absorption refrigeration an overview sciencedirect topics. Before moving further on differences lets have an overview of both the vapour compression and vapour absorption refrigeration system. Jun 01, 2017 rac hindi l 03 vapour compression refrigeration cycle by mr vikash kumar duration. The most common refrigeration system in use today involves the input of work from a compressor and uses the vapor compression cycle. 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. 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.
The purpose of a refrigerator is the removal of heat, called the cooling load, from a lowtemperature medium. Vcr uses mechanical energy as the driving force for refrigeration, while var uses thermal energy as the driving force for refrigeration. System description the layout of the system is shown in figure 1. Ppt vapour compression cycle powerpoint presentation free. It is also used in domestic and commercial refrigerators, largescale warehouses for. Download pdf lectures on vapour absorption refrigeration system what is vapour absorption refrigeration cycle. The vapour compression cycle which is used in vapour compression refrigeration system is nowadays used for all purpose refrigeration. It is also used in domestic and commercial refrigerators, largescale. 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 points which are required for engineering calculation are from h 1 to h.
Vapour compression cycle generally known as vcc is a refrigeration cycle. 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. Today we will study the difference between vapour compression and vapour absorption refrigeration system in detail. At the bottom of the articles you can download pdf. Vapor compression refrigeration system basic, working. Heat removed from the engine in the cooling system is recovered. Which device is used for the expansion of refrigerant in vapour compression refrigeration cycle. Case1 the basics of refrigeration cycle ph diagram analysis. Each stage operates on an ideal vapor compression refrigeration cycle with refrigerant4a as the working fluid. Twostage compression cycle with one evaporator and intercooling with flash gas 53. This amounts to 40% of the energy supplied in the fuel.
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