In a gas processing plant, propane refrigerant is typically condensed by cooling water or ambient air. Layout of the r22 vapour compression refrigeration system. In this article were going to be looking at how to design and analyse a refrigeration system. Refrigeration training course air conditioner working. Howmechanismworks what is vapour compression refrigeration. Jul 21, 2017 the first working vapor compression refrigeration system was built in 1834 by another american who was living in the uk, jacob jenkins. Vapourcompression refrigeration or vaporcompression refrigeration system, 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. In compression refrigeration system we used a compressor which is run by electricity but absorption refrigeration system always runs by using a heat source.
What is the working principle of vapour absorption. The operating principle of the refrigeration cycle was described mathematically by sadi carnot in 1824 as a heat engine. 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. In this article we will discuss about simple vapour compression refrigeration system.
Hvac and refrigeration system bureau of energy efficiency 73 figure 4. R4a refrigerant properties r4a, chemically 1,1,1,2tetrafluoroethane cf 3 ch 2 f is a nonflammable gas used primarily as a hightemperature refrigerant for domestic refrigeration and automobile air conditioners. The above figure shows simple vapour compression refrigeration system. The above figure shows the objectives of refrigerators and heat pumps. A refrigerator is machine which cool and maintain a body at a temperature below that of surrounding. This system consists of compressor, condenser, expansion valve and evaporator. 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. In these slides i have discussed about vapour compression system. Majority of refrigerator system works on vapour compression refrigeration system. This refrigeration system is different from compression refrigeration system. 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. However, for interested readers, closedcycle adsorption technology is briefly described below.
The required refrigeration capacity of a vapour compression refrigeration system with r22 as refrigerant is 100 kw at 30oc evaporator temperature. Working principle of ahucsufcuvahupahu and its chilled water pipe line. The ph and ts diagram for the simple vapor compression refrigeration cycle is shown in the figure for vapour entering the compressor is in dry saturation condition the dry and saturated vapour entering the compressor at point 1 that vapour compresses isentropic ally from point 1 to 2 which increases the pressure from evaporator pressure to condenser. The article explains one of the two refrigeration systems i. Read on for information about the vapor compression cycle, how it works, and how it is used in to provide refrigeration. In plants of today the most modern technology is being used for the design, the components and the control strategy, which, of course, improves the economic value and. Layout of the r22 vapourcompression refrigeration system. The vapor compression refrigeration cycle, step by step araner. The temperature at which a fluid boils or condenses is known as.
The working principle of a closedcycle solid desiccant based cooling system is. Jul 02, 2019 design and analyse a refrigeration system. Refrigeration and air conditioning systems onboard ships. Refrigeration is obtained as the refrigerant evaporates at low temperatures. Vapour compression cycle definite guide with video. During a vapor compression cycle, work is done on the fluid by the pumps between states 1 and 2 isentropic compression. Permissible for 8 hour working exposure niosh, osha 100.
Systems vcrs known in aviation as the vapor cycle machines vcm. Explain the function of primary and secondary refrigeration systems. Vapor compression refrigeration cycle working principle. A refrigeration system can also be used as a heat pump, in which the useful output is the high temperature heat rejected at the condenser. It has been and is the most widely used method for airconditioning of large public buildings, offices. Mechanism and working of a vapour compression refrigeration system with pv and ts diagram mecholic no comments.
The vapor compression refrigeration cycle is virtually rankine cycle with the. Vapourcompression refrigeration or vaporcompression refrigeration system vcrs, in which. Vapor absorption refrigeration cycle or vapor absorption refrigeration system vars pdf. Figure 81 plots the horsepower required per mmbtuh of cooling duty against the propane evaporating temperature for various propane condensing temperatures. Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Vapour compression refrigeration system with economiser largescale air conditioning units often use centrifugal compressors for the compression process. American engineer alexander twining took out a british patent in 1850 for a vapour compression system that used ether. Vapor compression refrigeration is one of the many refrigeration cycles available for use. As the name implies, these systems belong to the general class of vapour cycles, where in the working fluid refrigerant undergoes phase change at least. The highpressure vapour refrigeration is then cooled in the condenser at constant pressure.
The effect of superheating on vapour compression system. Performance analysis of vapour compression refrigeration system with r404a, r407c and r410a jyoti soni 1 and r c gupta corresponding author. This is the part of the refrigeration system that is doing the actual cooling. Vapour compression refrigeration working with pv and ts. Mar 26, 2007 vapor compression refrigeration cycle this refrigeration cycle is approximately a rankine cycle run in reverse. What is vaporcompression cycle refrigeration cycle. This blog post will explain how this vapor compression refrigeration cycle works and how it can be applied, or. First, evaporation is simply the process of vaporization these two terms are essentially synonymous. Gandhinagar institute of technology subject applied thermal and hydraulic engineering2140907 branch electrical topic refrigeration vapour compression refrigeration system 2. Detail explanation of working of refrigeration working vapour compression cycle. In vapour compression refrigeration system, at entrance to. For a closed cycle of refrigeration employing the condensable refrigerant vapour, the following processes are required. A vaporcompression refrigeration system plays an important role in the chemical. Vapor compression refrigeration system basic, working, parts of system, advantages, and disadvantages introduction.
How vaporcompression cooling works electronics cooling. 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. The interactive explanations give a comprehensive understanding on the air conditioner working principle. Refrigeration cycles the vapor compression refrigeration cycle is a common method for transferring heat from a low temperature to a high temperature.
A heat pump can be thought of as a heat engine which is operating in reverse. The most common refrigeration system in use today involves the input of work from a compressor and uses the vapor compression cycle. 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. Refrigeration requires continuous generation of pressurized refrigerant, which on condensing and expansion give. The basic components of any refrigeration system working on the vapour compression cycle, are the compressor, condenser, expansion valve, evaporator and the refrigerant fluid which is alternatively vapourized and liquefied during the refrigeration cycle. The refrigeration and air conditioning training course is a complete reference on the topic.
Mechanical refrigeration is a process for exchanging heat to effect a desired temperature in an. Vapor compression refrigeration an overview sciencedirect. In that case, it is not possible to admit vapour into the compressor at an intermediate pressure and hence an economiser cannot be employed. 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. The working principle of a closedcycle solid desiccant based cooling system is similar to that of a vapor compression refrigeration system. Vapor compression system and the refrigeration system parts in detail.
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. The first working vapor compression refrigeration system was built in 1834 by another american who was living in the uk, jacob jenkins. Jun 01, 2017 vapour compression problem 1 mechiteasy. The vapor compression refrigeration cycle, step by step. Explain the refrigeration vapour compression cycles of basic and direct staged systems. The principle of the system is to make use of two substances that can be separated when heated.
Domestic refrigerator working principle, electrical circuit diagram of a refrigerator, vapor compression system parts. What happens during each of the processes and physical changes to the refrigerant is explained as well. Refrigeration technology is commonly used in domestic and industrial applications. The purpose of a refrigerator is the removal of heat, called the cooling load, from a lowtemperature medium.
Alternatively, a refrigeration system can be used for providing cooling in summer and heating in winter. Illustrate, label and explain vapour compression and absorption refrigeration systems. System description the layout of the system is shown in figure 1. Vaporcompression refrigeration cycle this refrigeration cycle is approximately a rankine cycle run in reverse. Both a steadystate and a transient simulation will be considered. Schematic of a basic vapor compression refrigeration system it can be seen that the condenser has to be capable of rejecting the combined heat inputs of the evaporator and the compressor. A working fluid often called the refrigerant is pushed through the system and undergoes. Vapor compression system an overview sciencedirect topics. The cop of a refrigeration system also increases as a result of cascading. The adsorbent, maintained at a low temperature, adsorbs low pressure refrigerant vapor. Commercial refrigeration is concerned with the designing, installation, and maintenance of refrigerated fixtures of the type used by retail stores, restaurants, hotels, and institutions for the storing, displaying, processing, and dispensing of perishable commodities of all types. The condensation heat produced in the condenser is dissipated by means of a cooling tower, while the evaporator produces the refrigeration capacity, taking heat at a low temperature.
The first practical vapour compression refrigeration system was built by james harrison, a british journalist who had emigrated to australia. 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. The selection of working fluid has a significant impact on the performance of the. Refrigeration system operates on a vapor compression refrigeration cycle principle. The standard vapor compression refrigeration system is a condenser, evaporator, throttling valve, and a compressor. Conventional air conditioning systems, heat pumps, and refrigeration systems that are able to cool or heat, for heat pumps and dehumidify air in a defined volume e. We will cover the theory behind an ideal vapour compression cycle, so the performance of this would be slightly different to the real world scenario. Difference between vapour compression and vapour absorption pdf. Latent heat involved in phase change ensures high value of heat removal, while air refrigeration system has sensible heat only. The working substance is circulated in the system in which it alternatively evaporates and condenses. The training program covers both the vapor compression cycle and absorption refrigeration cycle. The system has a cool side and a warm side, and by pumping a fluid through the cool side it collects heat, and then pumps it to the warm side, where it expands, and gives up. It is a compression process, whose aim is to raise the refrigerant pressure, as it flows from an evaporator. While some people have viewed this method as environmentally harmful and inefficient, the cycle is still applicable in the industrial sphere.
In this type of refrigerator, refrigerant undergoes phase changes. The working fluid in a vapor compression cycle follows a closed loop and is. Fabrication and analysis of vapour compression system with. The effect of this superheating of vapour on the performance of the cycle cop can be studied from this diagram. In this chapter, only opencycle solid desiccant cooling technology has been discussed. Simple vapour compression refrigeration system with. The steam jet refrigeration system also known as ejector system refrigeration system is one of the oldest methods of producing refrigeration effect. This blog post will explain how this vapor compression refrigeration cycle works and how it can be applied, or you can watch the video explanation, here.
His 1856 patent was for a vapour compression system using ether, alcohol, or ammonia. In this system, the working substance is a refrigerant like nh 3, r11, r12. The low pressure saturated vapour refrigerant from evaporator drawn into the compressor through suction valve. How it works working principle of ammonia absorption systems. Refrigeration onboard ships marine engineering study.
A working fluid often called the refrigerant is pushed through the system and undergoes state changes from liquid to gas and back. Fabrication and analysis of vapour compression system with ellipse shaped evaporator coil abstract. The working fluid in a vaporcompression cycle follows a closed loop and is reused constantly. The refrigerant is let into and measured by a flow control device, and eventually released to the compressor. In a compression refrigeration machine a mechanical compressor is used to take the refrigerant vapour from the lower evaporation pressure to the higher condensation pressure. Vapor compression refrigeration an overview sciencedirect topics. The input to the system is in the form of mechanical energy required to run the. The principle parts which are used in this system are. If you continue browsing the site, you agree to the use of cookies on this website.
Vapor 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. Heat pump and refrigeration cycles can be classified as vapor compression, vapor absorption, gas cycle, or stirling cycle types. This course is an overview of vapor compression refrigeration cycle, principles of heat generation, transfer and rejection. Vapor compression refrigeration system basic, working, parts of.
Apr 23,2020 in vapour compression refrigeration system, at entrance to which component the working fluid is superheat vapour. Nov 02, 2016 on this channel you can get education and knowledge for general issues and topics. Edurev mechanical engineering question is disucussed on edurev study group by 3 mechanical engineering students. 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. In the vapor absorption process, the compression process of the vapor compression cycle is replaced by an absorber, a generator and a pump.
How it works working principle of ammonia absorption systems the technology of absorption refrigeration plants has been used for cooling purposes for over a hundred years now. The refrigerant then compressed to high pressure by the compressor and then delivered to the condenser through the delivery valve. Domestic refrigerator working principle your electrical. Comparing the absorption refrigeration cycle with the more familiar vapor compression refrigeration cycle is often an easy way to introduce it. Refrigeration training course air conditioner working principle. The science behind refrigeration berg chilling systems inc. In some systems, the compressor is driven by an external motor called opendrive or open drive system. Refrigeratordefinition, main parts or component, working principle, advantages, disadvantages, application, pdf march 22, 2019 difference between vapour compression and vapour absorption refrigeration system with pdf. It is also used in domestic and commercial refrigerators, largescale warehouses for chilled or frozen storage of foods and meats, refrigerated trucks and railroad cars, and a host of other commercial and industrial services. The compressor constricts the refrigerant vapor, raising its pressure and temperature, and pushes it into the coils of the condenser on the outside of the refrigerator. Sep 05, 2018 there are many type of refrigeration system one of them is vapour absoption refrigeration system. Vapour compression refrigeration system slideshare.
The vapor compression refrigeration cycle involves four components. The latent heat of vaporization of the refrigerant is used to transfer large amounts of heat energy. Vapour compression refrigeration system refrigeration vapour. The refrigeration cycle and air conditioning cycle basics are covered stepbystep, to give a complete understanding on the refrigerator and air conditioner working principle. It condenses and evaporates at temperatures and pressures close to the atmospheric conditions. There is no work is done by the fluid since between stages 3 and 4 the process is isenthalpic.
If the vapour is compressed after it has become dry and saturated then the vapour becomes superheated. Heat pump systems other refrigeration cycles cascade refrigeration systems very low temperatures can be achieved by operating two or more vapor compression systems in series, called cascading. Advantages and disadvantages of air refrigeration system mechanism and working of a vapour compression refrigeration system comparison between heat engine, refrigerator, and heat pump. Refrigeration onboard ships marine engineering study materials. Vapour compression refrigeration or vapor compression 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. The refrigerant is let into and measured by a flow control device, and eventually released to the. Working of refrigerator and refrigeration principle. Design a refrigeration system the engineering mindset. Apr 02, 2016 vapour compression refrigeration system 1. During suction stroke of the compressor, wet vapor refrigerant is drawn from the evaporator and compressed adiabatically to high pressure and high temperature.
There are no appreciable pressure drops as the refrigerant flows through the condenser and evaporator. Feb 10, 2017 the presentation will give you idea about the vapor compression refrigeration system. Components of vapour compression refrigeration cycle. Since the vapor compression cycle is against the second law of thermodynamics, some work is necessary for the transfer to take place. Vocabulary background in the thermodynamics and refrigeration literature, several words are used interchangeably that can cause confusion. This refrigeration cycle is approximately a rankine cycle run in reverse.
A correlated understanding on concepts like refrigerator cop, hrf, nre, etc are provided with respect to mollier diagrams. Vapor compression refrigeration system basic, working. Mechanism and working of a vapour compression refrigeration. Explain vapour compression refrigeration cycle on ts and ph. The vapor compression refrigeration cycle is nearly 200 years old, but it does not seem ready to leave the scene any time soon. It works on the principal that compressing a liquid which is basically incompressible is much more economical than compressing a gas. Modern vapor compression systems for comfort cooling and industrial refrigeration use one of several types of compressors.
Simple vapour compression refrigeration system with diagram. Next the refrigerant flows through the condenser, where it condenses from vapor form to liquid form, giving off heat in the process. Vapour compression systems are used for refrigeration and air conditioning. The vapor compression cycle in aircraft airconditioning. Initially the system was singlestage with a single compressor compressing the refrigerant vapour from evaporator to a condenser operating at 1500 kpa pressure. Vapor compression refrigeration systems are used for a variety of cooling refrigeration applications. This case study demonstrates the modeling of a vapour compression refrigeration system using r22 as refrigerant. Working principle, types and comparison with vapor compression system, saving potential 4. A refrigeration system is a heat pump, just like a heater is a heat pump. This article gives a detailed and logical introduction to the workings of refrigerators using the vapor compression cycle. It readily evaporates and condenses or changes alternatively between the vapor and liquid phase without leaving the refrigerating plant.
197 378 454 1179 282 1259 1395 1018 1427 1215 965 163 1354 156 1309 1070 828 768 614 489 912 1184 245 1065 1294 1225 1353 12