The institute of refrigeration refrigerants americas. The following are the important requirements of a refrigerant. Guidelines for the use of hydrocarbon refrigerants in static. Its gwp of 675 is within the acceptable limits for refrigerant gases used in new equipment splits with a load less than 3 kg, put on the market from 01012025, in. Comparative analysis of r290r600a with commonly used. Different refrigerants are used for different temperature conditions and there is no ideal one that is suitable for all conditions.
Pdf refrigeration and airconditioning play a vital role in domestic and industrial. The hydrofluorocarbons are refrigerants that contain no chlorine and are not harmful to the ozone layer odp 0, see section 5. Refrigerants and their application presented by thomas e. Which of the following is not a desirable property for new refrigerants. Click download or read online button to get refrigerant tables and charts book now. Refrigerant types, issues, trends and future options. Properties of refrigerants n low boiling point and high latent heat of vaporization n dense vapor n low toxicity n non flammable n low miscibility with oil. If there is toxicity identified in this small amount, the substance is a class b refrigerant. Ashrae position document on refrigerants and their responsible use 2 executive summary refrigerants are the working fluids in refrigeration, airconditioning, and heatpumping systems. Just as tradeoffs are inevitable so are limitations. Refrigeration may be defined as a process of removing heat from a substance and pumping it to the surroundings. The design of the refrigeration equipment depends strongly on the properties of the selected refrigerant. Toxicity classification of refrigerants is assigned to classes a or b.
Thus, a variety of refrigerants having a range of properties is needed to meet the requirements of various applications. Following the discovery that some of these chemical compounds may be harmful to the environment, they are being replaced with more environmentally friendly alternatives see figure 5. Jul 17, 2017 if there is toxicity identified in this small amount, the substance is a class b refrigerant. Hydrocarbons are some of the key low gwp and energy efficient refrigerants that are being considered as good alternative refrigerants for a number of applications. Effects of key refrigerant properties on system performance. It would not cause ozone depletion or climate change. An alternative refrigerant to chlorofluorocarbons and their substitutes such as r 12 and r 4 a and for r 22, and demonstrating improved performance as a refrigerant than those substituted for while having the properties of being nontoxic, noncorrosive, nonflammable and safer to the environment including a blend of one or more of fluorocarbons known in the industry as r 1216 and r 22. In the design of the potential refrigerants, consumer preference functions were used to evaluate refrigerant properties consumer preference functions can also be used to solve for the demand d1 of a new refrigerant when it is in competition with an existing refrigerant. The general conclusion of the thesis is that the refrigerant affects all of the measured properties negatively on the subject of lubrication and life of the rolling element bearing. Desirable properties and commonly used refrigerants. The process is not easy, and although there are alternatives to old refrigerants, the new ones are usually not flawless. Refrigerants for vapour compression refrigeration systems.
Sep 17, 2014 color codes of refrigerants easy recognize gas cylinder different refrigerant has different color coding few examples are given below. Comparison of environmental impacts and physical properties of refrigerants ko matsunaga executive summary even before the invention of refrigeration, people wanted to improve their life by using ice to provide cold drinks and preserve food. Comparative analysis of r290r600a with commonly used refrigerant ajoy bhargav1, nitin jaiswal2 1,2 mechanical engg. Polyol ester poe generally exhibit excessive solubility with hc refrigerants. R32 is suitable for new equipment specifically designed for r32, in applications that used to use r410a. Since different fluids have the desired traits in different degree, choice is a matter of tradeoffs. This paper deals with the thermoeconomic analysis and multiobjective optimization of simple vapour compression refrigeration system using three low gwp refrigerants namely, r152a, r600a and r1234ze. This also reduces the initial cost of the refrigerant used in the system. The search for alternative refrigerants a molecular approach. In the last two centuries, human ingenuity made it. Usually, a fluid, used in a heat pump and refrigeration cycle that can extract heat from another body or substance. Thermodynamic properties of duponttm freonr 12 r12. Refrigerants are divided into groups according to their chemical composition.
Effects of refrigerant properties on refrigerant performance citeseerx. May 01, 2014 following are the desirable properties of a primary refrigerant. Refrigeration engineering and cold chain credit hours. Fellow ashrae mcquay international staunton, virginia usa 1 what is a refrigerant.
As the refrigerant flows through the continuous vapor compression cycle it absorbs heat from a lowtemperature reservoir and deflects it into the atmosphere. Class 1 refrigerants are completely nonflammable, class 2 types are moderately flammable and class 3 substances are highly flammable. Today the hfc r404a is one of the most commonly used refrigerants in the united states and in the world. Policylegislation on fgases and alternatives two environmental frameworks one goal the montreal protocol and the kyoto protocol. Low gwp and zero odp from a sustainable environment. Whenever we choose them for particular use properties of refrigerants also plays a vital role in economic and environmental friendly application. High latent heat of refrigerant at evaporator temperature is desirable. A refrigerant must satisfy many requirements, some of which do not directly relate to its ability. Hfc refrigerants are not miscible with the mineral oils used in cfc refrigeration systems.
It has a boiling point of 21f at atmospheric pressure. Refrigerant tables and charts top results of your surfing refrigerant tables and charts start download portable document format pdf and ebooks electronic books free online rating news 20162017 is books that can provide inspiration, insight, knowledge to the reader. The thermodynamic properties of refrigerants columbushoa. Properties of commonly used refrigerants a refrigerant is a substance or mixture. You can find it most commercial refrigeratorsfreezers, in vending and ice machines, in refrigerated transport, and in specific industrial applications. Pressure ratio should be small for higher isentropic and volumetric efficiency, and the refrigerant must be miscible with oil for piston. This article describes thermodynamic properties of the refrigerants the ideal refrigerant. New refrigerants to replace cfcs comprise an active area of development. Natural and synthetic refrigerants, global warming.
Polyalkylene glycol pag soluble or partially soluble with hc refrigerants depending upon the conditions. Theory and applications by james k carson covers the basic thermodynamic and heat transfer considerations of the vapour compression cycle followed by the major applications of refrigeration in the areas of food preservation, human comfort and cryogenics. As such, there is no refrigerant that can be advantageously used under all. The article focuses on the criteria for refrigerant selection, including discussion of the transitional refrigerants hcfcs, chlorinefree refrigerants hfcs, and halogenfree refrigerants. Policylegislation on fgases and alternatives two environmental frameworks. The flood of the airconditioner, that is, the refrigerants, their properties, merits and demerits are summarized. Hydrocarbons natural refrigerants for lowering gwp danfoss. What is a refrigerant and desired properties of a refrigerant scribd. Refrigeration n changes phase due to change in pressure n most common cryogens are n solid carbon dioxide n liquid carbon cook chill systems n used to replace warm. The effect of condenser temperature and evaporation temperature on cop, refrigerating e consider super cooling also. Desirable properties of refrigerant absorbent mixtures. Following are the desirable properties of a primary refrigerant. R22 light green r4a light sky blue r404a orange the name label of the gases are given on the cylinder. However, at condensation, high density, thermal conductivity and latent heat of vaporizations are desirable properties for effective cooling and heating with a small temperature rise during compression.
Rac mechanical engineering btech 78th ptu previous years. R717 ammonia r290 r600a propane and isobutane hydrocarbons r744 carbon dioxide r1234yf r1234ze hfo hydrofluoroolefin the table below shows the respective properties of the low gwp refrigerants under consideration hfc natural hfo. Refrigeration equipment an overview sciencedirect topics. Download as ppt, pdf, txt or read online from scribd. The following is a list of refrigerants with their typeprefix, ashrae designated numbers, iupac chemical name, molecular formula, cas registry number blend name, atmospheric lifetime in years, semiempirical ozone depletion potential, net global warming potential over a 100year time horizon, occupational exposure limitpermissible exposure. There is no ideal refrigerant which can be used for all type of applications i. Us5514595a method for analyzing refrigerant properties. Thermodynamic analysis of vapor absorption refrigeration. Refrigerant absorbent mixtures for vapour absorption cooling system should possess some desirable properties like the refrigerant should be more volatile than the absorbent in other words the boiling point of refrigerant. The refrigerants have a thermodynamic property charge. Key properties of the main refrigerants are given in table 3.
The sample chamber and passage are evacuated, and the. Color codes of refrigerants easy recognize gas cylinder different refrigerant has different color coding few examples are given below. Ebook refrigerant tables and charts as pdf download. Natural refrigerants sustainable ozone and climatefriendly alternatives to hcfcs introduction dr. What is a refrigerant and desired properties of a refrigerant free download as pdf file. In particular, physical properties of refrigerants are useful for determining the applicability of a refrigerant under design operating conditions. This section presents data for the thermodynamic and transport properties of refrigerants, arranged for the occasional users. In some applications it may be necessary to consider other properties of the refrigerant, such as its interaction with the process fluid in the event of a pinhole leak. Refrigerants are widely used in refrigeration cycle where cooling effect below the. Table a1 molar mass, gas constant, and criticalpoint properties table a2 idealgas specific heats of various common gases table a3 properties of common liquids, solids, and foods table a4 saturated watertemperature table table a5 saturated waterpressure table table a6 superheated water table a7 compressed liquid water table a8 saturated icewater vapor. Jun 02, 2019 properties of commonly used refrigerants a refrigerant is a substance or mixture. The liquid has to vapourise at the evaporator coil to cause cooling. With all the advances that have been made in this and other industries over t.
The choice of refrigerant is becoming more complex and this chapter can only be considered as an introduction. The cfcs r12, r11, r114 and r502 together with hcfc r22 became the definitive refrigerants. Refrigerant tables and charts download ebook pdf, epub. Engineering toolbox resources, tools and basic information for engineering and design of technical applications. Dec 12, 2005 this article has been excerpted from a comprehensive white paper, refrigerants for commercial refrigeration applications, issued by copeland corp. Refrigerants classification and nomenclature of refrigerants. The refrigerant in any refrigerator or air conditioner flows continuously through the vapor compression cycle, absorbing the heat in the evaporator and releasing it in the condenser. Ashrae position document on refrigerants and their. It was soon evident, though, that the lack of chlorine and that the new ester oils did not have the same good lubrication properties as mineral oil and cfc refrigerants. This brochure provides selected properties information for solstice yf including thermodynamic data, transport prop erties, and flammability characteristics. Usually, a fluid, used in a heat pump and refrigeration cycle that. They absorb heat from one area, such as an airconditioned space, and reject it into another, such as outdoors, usually through evaporation and condensation. In higher concentrations, its odor resembles that of carbon tetrachloride.
Due to these menace, r4a should be prohibited to make way for desirable environmentally efficient refrigerants. Development of the refprop database and transport properties of refrigerants final report mark o. The liquid at the evaporator coil should therefore vapourise easily, otherwise the compressor will have to create too much of vacuum to cause the liquid to vapourise. The refrigerants are expensive and have negative environmental impacts when released to the atmosphere. Class a signifies refrigerants for which toxicity has not been identified. The ashrae position document on refrigerants and their responsible use was developed by the societys. However, their impact on global warming is very large compared with traditional refrigerants. Solstice yf was originally developed as a low global warming potential replacement for r4a in the automobile airconditioning application. Desirable properties of refrigerants chemical engineering site. Volkmar hasse, gtz proklima, germany preface volkmar hasse, gtz proklima i. Desirable thermodynamic, chemical and physical properties of refrigerants. Pdf refrigerant types, issues, trends and future options.
This site is like a library, use search box in the widget to get ebook that you want. The most common hfc refrigerants available since the ban on hcfcs are presented in table 5. Mclinden physical and chemical properties division national institute of standards and technology 325 broadway, mailstop 838. In the last two centuries, human ingenuity made it possible to control fully. Thermodynamic and transport properties of refrigerants are necessary for predicting. Refrigerants properties pdf product data summary and thermodynamic tables. Refrigerant 12 dichlorodifluoromethane properties of saturated liquid and saturated vapor. For refrigerants this means certain chemicals will be phased out and others restricted. The refrigerant is a heat carrying medium which during their cycles i. New, natural and alternative refrigerants by dr s f pearson of star refrigeration limited introduction it is an honour to be invited to present this paper despite the rather daunting title. All refrigerants which damage the ozone layer have now effectively been banned, however many substances have a significant gwp that is released into the atmosphere through leakage. Download limit exceeded you have exceeded your daily download allowance.
Here are some of the desirable properties of refrigerant explained in detail. Hence, new synthetic ester lubricants were developed for this application. Refrigerant oil miscibility is desirable to a degree that. Safety properties of refrigerants considering flammability and toxicity are defined by ashrae standard 34 1. The production and use of cfcs is restricted by the montreal protocols. In particular they were nontoxic, nonflammable and with good thermodynamic prop erties and oil miscibility characteristics. These physical properties of refrigerants help us select the proper refrigerant for the application as per our requirement. R32 refrigerant gases and products for air conditioning. Refrigerant selection involves compromises between conflicting desirable thermophysical properties. The ideal working fluid or often called refrigerant would have favorable thermodynamic properties, be noncorrosive to mechanical components, and be safe, including freedom from toxicity and flammability. Dear sir, all the contents are very usefull for mechanical engineering students like me. It is odorless in concentrations of less than 20 percent by volume in air.
The liquid at the evaporator coil should therefore vapourise easily, otherwise the compressor will have to create too much of. The weight of the refrigerant required to be circulated in the system per unit of refrigerating effect will be low if the latent heat of refrigerant is high. Physical properties of refrigerants molecular weight, boiling, freezing and critical points. A blank numerically shows the thermodynamic properties of a refrigerant under saturated conditions. In some applications it may be necessary to consider other properties of the refrigerant, such as its interaction with. One or more properties of a refrigerant sample, such as composition, purity or both composition and purity, are analyzed for purposes of refrigerant recovery and reuse by providing a refrigerant cell having a chamber for containing a refrigerant sample and a passage for connecting the chamber to a source of refrigerant in vapor phase. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Refrigerants are widely used in refrigeration cycle where cooling effect below the atmospheric temperatures are needed.
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