Central test takes the greatest care to regularly assess the psychometric properties of all its tests. Psychrometrics is the science of studying the thermodynamic properties of moist air. When the air is hot, it can contain a large amount of moisture vapour, sometimes as much as 5% by volume. In the data center industry for computer room air conditioners, the two most common refrigerants are r407c and r410a. The psychrometric chart and its use psychrometry is an impressive word which is defined as the measurement of the moisture content of air. Technical information at22 thermodynamic properties of dupontz freon. Create psychrometric processes by plotting points then connecting them with process lines. The psychrometric chart graphically displays several physical properties of air over a broad range of conditions. To quote the 1989 ashrae handbook of fundamentals, psychrometrics deals with the thermodynamic properties of moist air and uses these.
R4a is also known as tetrafluoroethane cf3ch2f from the family of hfc refrigerant. Thermal properties of each refrigerant 32 table 14. Buy refrigeration and psychrometric charts with property. Psychrometric chart 5,000 feet barometric pressure. The process involves changes of thermodynamic properties of the refrigerant and the energy transfer between the refrigerant and the surroundings and is illustrated below. Thermodynamic properties of duponttm freonr 12 r12. Cooling the dry air, which is comparatively simple and involves sensible cooling only. Table a18 idealgas properties of nitrogen, n 2 table a19 idealgas properties of oxygen, o 2 table a20 idealgas properties of carbon dioxide, co 2 table a21 idealgas properties of carbon monoxide, co table a22 idealgas properties of hydrogen, h 2 table a23 idealgas properties of water vapor, h 2 o table a24 idealgas.
Summary of environmental impacts of each refrigerant 28 table. Thermodynamic properties of duponttm freonr 22 refrigerant author. The water vapor is such a small part of the air that we usually ignore its sensible heat. Desirable properties of refrigerants chemical engineering site.
Usually, a fluid, used in a heat pump and refrigeration cycle that can extract heat from another body or substance. Apr 12, 2020 refrigerants are widely used in refrigeration cycle where cooling effect below the atmospheric temperatures are needed. Marvin, us weather bureau devised psychometric tables for. Read refrigeration and psychrometric charts with property tables s. Refrigerant tables and charts download ebook pdf, epub. Ebook refrigerant tables and charts as pdf download portable. For professional reports, use this electronic psychrometric chart tool. Email a list of all the points and their properties for a completed chart, along with a pdf of the chart itself. These charts focus on the range of temperatures most suitable for comfortcooling hvac applications, and include the trane coil curves, which depict the condition of the air leaving a cooling coil. Duponttm refrigerants, technical information keywords. Refrigerant properties refrigerant selection involves compromises between conflicting desirable properties.
The amount of moisture vapour in the air varies quite significantly under different conditions. Psychometric properties periodic assessment of validity and finetuning are crucial for longterm survival and effectiveness of any psychometric test. Buy refrigerant and psychrometric properties table. Thermodynamic properties of duponttm freonr 22 refrigerant. In cooling air, such as in summer air conditioning, we are chiefly concerned with. This analysis can be performed using the psychrometric chart. R410a or r407c know the facts we are all aware that r22 refrigerant was phased out due to the montreal protocol which took affect in january 2010 and alternative refrigerants are now available. With the help of psychometric properties chart we get other. Ebook refrigerant tables and charts as pdf download. 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 holding of foods n cook chill system.
R1270 care 45 propylene r1270, also known as care 45, is refrigerant grade propylene propene, a natural, or not in kind, refrigerant suitable for use in low and medium temperature refrigeration applications. The mass balance for the refrigerant flow in the ground heat exchanger can be denoted as. A next generation refrigerant properties database purdue epubs. If possible, the refrigerant must be odorless, but easy detection in the air is. A thorough understanding of psychrometrics is of great significance, particularly to the heating, ventilating, and airconditioning hvac community. The working fluid desirable properties are related to thermodynamic and physical properties which lead to efficient cooling or heating factor and effective design of equipment, such as high evaporation heat, high volumetric refrigeration. Figure a15 nelsonobert generalized compressibility chart.
Refrigerant r4a properties thermodynamic properties of refrigerant r4a. Pdf fossil fuels are depleting day by day due to rapid industrialization and. Knowing the relationship of these air properties aids the task of air. 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. The thermochemical and physical properties of each refrigerant were used to. Here are some of the desirable properties of refrigerant explained in detail. Refrigerant r22 properties properties of refrigerant r22 dichlorodifluoromethane saturated liquid and saturated vapor imperial and metric units.
Refrigeration tables with chart r s khurmi j k gupta abebooks. 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 flood of the airconditioner, that is, the refrigerants, their properties, merits and demerits are summarized to map the various types and their classifications. The refrigerants have a thermodynamic property charge. To assure that the oil gets out of the system, the oil and refrigerant must be miscible with each other and have the right pour point. Cooling efficiency of each refrigerant 25 table 11. This program is based on the most accurate pure fluid and mixture. Khurmi and a great selection of related books, art and collectibles available now at. Refrigerants with higher boiling points tend to be more efficient and may work well in a smaller machine. In addition, you can doubletap a point to display the point properties and then edit them. There are various tables, which are used to represent the properties of refrigerant for each kind. Coolerado 5000 feet psychrometric chart teachengineering. In broader terms it is the science and practices associated with atmospheric air mixtures, their control, and the effect on materials and human comfort. Psychrometrics deals with the thermodynamic properties of moist air and uses these properties to analyze conditions and processes involving moist air.
A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. It is nontoxic, with zero odp ozone depletion potential and very low gwp global warming potential. Thermal properties of each refrigerant 24 table 10. With the discovery of the damaging effect of cfcs and hcfcs refrigerants to the ozone layer, the hfc family of refrigerant has been widely used as their replacement.
Refrigerants color codes refrigerants and their color codes. Lubrication of ball bearings in refrigeration compressors 3 how much oil will go out in the refrigeration cycle. Energy consumption and environmental impacts 26 of each refrigerant during operation table 12. The present tables and charts of important properties of refrigerants and also psychrometrics have been compiled for the use of students of mechanical engineering specializing in refrigeration and air conditioning. Tables of the thermodynamic properties of dupont freon. Psychrometrics is the science of air and water vapor that deals with the properties of moist air. Pdf refrigerant types, issues, trends and future options. These properties can be divided into favourable thermodynamic, chemical and physical properties. Buy refrigeration and psychrometric charts with property tables s. A completely revised version of the refprop refrigerant properties database is described. The performance characteristics of gshp are computed in terms of cop and energetic. When it is cold, its capacity to hold the moisture is reduced. Hvac made easy overview of psychrometrics course content introduction psychrometrics derived from the greek.
Table aesuperheated refrigerant4a figure a14eph diagram for refrigerant4a table a16eproperties of the atmosphere at high altitude table a17eidealgas properties of air table a18eidealgas properties of nitrogen, n 2 table a19eidealgas properties of oxygen, o 2 table a20eidealgas properties of carbon dioxide, co 2. Psychrometrics deals with the thermodynamic properties of moist air and uses. Jul 17, 2017 a refrigerant with a lower boiling point tends to have a better ability to cool. These detailed properties can be used by the students of polytechnics, undergraduate and postgraduate engineering students and for a.
This section presents data for the thermodynamic and transport properties of refrigerants, arranged for the occasional users. Psychometric properties psychometric testing online. Table a12 saturated refrigerant4a figure a29 generalized enthalpy. If possible, the refrigerant must be odorless, but easy detection in the air is desirable.
1488 801 51 1565 51 621 1128 983 1323 1471 349 45 1284 362 1041 358 1516 867 698 1066 1541 292 516 168 808 198 315 12 1461 27 1313 768 323 1371 573 640 625 1371 441 55 205 485 219 1008