High latent heat of vaporization. Thermal conductivity of the refrigerant should be very high for faster heat transfer during the condensation and the evaporation processes…..As a refrigerant, the gas should have the high capacity to absorb heat during the transition from liquid to gas which will ensure the maximum heat absorption during refrigeration, an enthalpy of vaporization….. Refrigerant R134A −101 ... Heat is dissipated away from the body due to the high latent heat of vaporization of water. × Hence why the heat absorption and heat rejection heat exchangers are called the evaporator and the condenser respectively. I have been comparing values of latent heat of vaporization - R12 is about 166 kj/kg and r134a is 215kg/kg, which means for R134a that for any given liquid amount in the evaporator, it can absorb more energyfrom the incoming air from the blower until it evaporates compared to R12, which would mean it can cool more air for a longer time. It results in a high refrigerating effect and a low rate of refrigerant in circulation. the vaporized refrigerant can be made to give up the latent heat of vaporization that it absorbed in the evaporator is by cooling and condensing it. Latent heat of vaporization A refrigerant should have a high latent heat of vapour at the evaporator temperature. Since a refrigerant’s goal is to move heat, an ideal refrigerant should have a high latent heat of vaporization. When there is a breeze, evaporative cooling is highly effective. Heat energy required to change a liquid to a vapor without raising its temperature ... A. low refrigerant level B. high refrigerant level C. contamination caused by desiccant breakdown ... C. latent heat. The latent heat of fusion and vaporization both involve the heat required to change the state of a substance without a change in temperature. Latent heat of vaporization is a physical property of a substance. As previously stated, the molecules of a substance in the liquid phase have more internal energy than solid ones, so in solidification energy is released instead of absorbing it, as an infusion. High latent heat of vaporization is an asset for refrigerants, because most of the heat absorption and heat rejection in the vapor-compression refrigeration cycle occurs as a phase change. Cooling via perspiration is affected by latent and sensible heat. (d) Low COP and low freezing point. 6. 5. 2. ‘Specific Enthalpy of Vaporisation’ (latent heat) of refrigerant should be high. Cost is always a factor in selecting a refrigerant. However, it's much harder to cool down in a sunny location than in a shady one because sensible heat from absorbed sunlight competes with the effect from evaporation. It should be non-flammable, non-explosive and chemically stable. the vaporized refrigerant can be made to give up the latent heat of vaporization that it absorbed in the evaporator is by cooling and condensing it. The liquid refrigerant in the evaporator absorbs its latent heat of vaporization, and in the process changes from a liquid to a vapor. The gas refrigerant within the condenser rejects its latent heat of vaporization… This temperature change during a phase change is due to the energy released from the potential energy stored in the bonds between the particles, and not due to the energy release from the kinetic energy of the particle. Otherwise mass flow rate will be high. Fire Load Calculation: Latent Heat Of Vaporization - posted in Relief Devices Forum: Hi all, I have a question regarding latent heat of vaporization. It should be non-corrosive, non-toxic and non-poisonous. 2. Nusselt number (NN) is given by A. NN = hl/k Solution (By Examveda Team) -The refrigerant should have low boiling point and low freezing point. 7. Because high specific heat decreases the refrigerating effect per kg of refrigerant and high latent heat at low temperature increases the … High latent heat of vaporization to get more refrigeration effect. Join us (login) to get full access : Please sign up to connect and participate. 3. The specific heat of … When the energy of a system changes because of a temperature difference between the system and its surroundings, we say that energy has been transferred as heat (q). EQ-COMP software is showcased on www.eq-comp.com website and the results of the software can be … Latent heat of vaporization A refrigerant should have a high latent heat of vapour at the evaporator temperature. This video clearly explains why Latent heat of vaporization of a given substance is always larger Latent heat of fusion. Two common forms of latent heat are latent heat of fusion and latent heat of vaporization . refrigerant with a lower latent heat of vaporization will absorb less energy during evaporation than those with higher hfg. It is therefore a measure of the cooling potential of the refrigerant circulated through a refrigeration system. The gas refrigerant within the condenser rejects its latent heat of … •Thermal conductivity :- It should have high thermal conductivity. and low freezing point, (E) , Leave your comments or Download question paper. Higher latent heat of vaporization of the refrigerant will result in lower mass flow rates according to the Heat transfer equation. High latent heat of vaporization to get more refrigeration effect. Dielectric strength: A high value of latent heat of vaporization implies that the refrigerant has to absorb a relatively large amount of heat during phase change (liquid-vapor), or, in other words, the cooling effect (which is the sole output for which refrigerators are manufactured and installed) can be enhanced. With. The refrigerant is a heat-carrying medium which during their cycle (i.e comparison, condensation, evaporation) in the refrigeration system absorbs heat from allow temperature system and discards the eat so absorbed to higher temperature system. 8. Latent heat of vapourisation of water at 1 bar, $100^\circ C$ is $2257 \frac{kJ}{kg}$. Latent heat of solidification. 1. Flip the page to see why this is so important. Latent heat is the heat absorbed or released as the result of a phase change. •Latent heat of vaporization :- It should have high latent heat of vaporization. High latent heat of vaporization. Paste as plain text instead, × 9. 5. ; Example - Boiling Water at 100 o C, 0 bar (100 kPa) Atmospheric Pressure. Otherwise mass flow rate will be high. 10. The ideal refrigerant should be: A) have a low latent heat capacity B) have a high boiling point C) have high condensing pressure D) be environmentally … In some applications, low toxicity and flammability are essential factors. High critical temperature to have large isothermal energy transfer. In addition, latent heat storage has the capacity to store heat of fusion at a constant or near-constant temperature that corresponds to the phase transition temperature of the phase change material (PCM). It should be environment-friendly. It should make leaks easy to detect and locate. ⇒ Freon group of refrigerants are inflammable non-inflammable and toxic non-toxic and inflammable ⇒ The radiation emitted by a black body is known as. 7. The heat of vaporization of … When choosing a refrigerant, it is suggested to have a high heat of evaporation, as it keeps the mass flow rate low...why is this? 4. In that case the chemical stability of the refrigerant may be an important property. All rights reserved. This brings us around to the most important characteristic of a refrigerant: the relationship between vapor pressure and temperature. 3. It should have low specific heat of liquid (to reduce vaporization during throttling). 5. Water has latent heat of vaporization of 540 calories per gram, the amount of heat energy that is necessary to convert 1 g of liquid water at 100°C to steam at 100°C, or 40.71 kJ/mol or about 2,260 kJ/kg water. Ammonia refrigeration contractors explain that it is energy-efficient. Thermal Conductivity: Thermal conductivity of the refrigerant should be high for faster heat transfer during condensation and evaporation. The important properties such as latent heat of vaporization and specific heat depend on the molecular weight and structure of the molecule. The good properties of a refrigerant are as follows: High critical temperature to have large isothermal energy transfer. © B-Cubed, 2003, 2005, 2006, 2014, 2018. Thanks in advance :) High Latent Heat of Vaporization. It results in high refrigerating effect per kg of refrigerant and which reduces the mass of refrigerant to be circulated per ton of refrigerants . - It must have low specific heat and high latent heat. 8. The heat energy is used in breaking the hydrogen bonds which hold the molecules of … Because of the relatively high temperature of the available cooling medium, the only way to make the vapor condense is to compress it. Latent Heat vs Sensible Heat . The difference will give you the latent heat for the mixture. by:Arkool 2021-01-18. Enthalpy of vaporization: To ensure the maximum heat absorption during refrigeration, a refrigerant should have a high enthalpy of vaporization. Every kilogram of liquid refrigerant vapourised at the evaporator coil should take away a large amount of heat, i.e. Refrigerant 1. The good properties of a refrigerant are as follows: High critical temperature to have large isothermal energy transfer. It should be oil miscible. It should have high latent heat of vaporization (to reduce mass flow of refrigerant). The specific heat of liquid should be as small as possible and of vapour should be as high as possible to give less superheating of vapour. The liquid refrigerant in the evaporator absorbs its latent heat of vaporization, and in the process changes from a liquid to a vapor. The difference will give you the latent heat for the mixture. No latent heat is the amount of energy in the form of heat that the liquid gives off or absorbs to change state. •Critical pressure and temperature :- It should be above the condensing pressure and temperature. Thanks in advance :) These names describe the direction of energy flow when changing from one phase to the next: from solid to liquid, and liquid to gas. In vapour compression refrigeration, the vapour is drawn in the compressor cylinder during its suction stroke and is compressed adiabatically during the compression stroke. A refrigerant should have a high latent heat of vapour at the evaporator temperature. Therefore the refrigerant vapors should be easily condensible. More heat can be absorbed and ejected in each cycle of refrigeration. You can share the question You can get updates of new questions on Facebook linkedin twitter & google plus Why high latent heat of vaporization is desirable in refrigerant ? Which of the following best describes the principle of latent heat of vaporization? When the air moving over the evaporator has more moisture in it and therefore a higher RH and dewpoint the surface temperature of the coil is increased so long as the coil temperature is below the air dewpoint. The temperature for a given pressure at which the gaseous refrigerant begins to condense into a liquid.   Pasted as rich text. Latent heat energy storage is a near-isothermal process that can provide significantly high storage density with smaller temperature swings in comparison with sensible storage systems. When the refrigeration system obtains the same cooling capacity, the large latent heat of vaporization can reduce the refrigerant circulation. Refrigerants are chosen because of their high latent heat capabilities, the amount of pressure need to hold the refrigerant in liquid form prior to … Latent heat is energy released or absorbed, by a body or a thermodynamic system, during a constant-temperature process. A. 2. Below are some of the reasons why the use of ammonia as a refrigerant has gained popularity. More heat can be absorbed and ejected in each cycle of refrigeration. When a material in liquid state is given energy, it changes its phase from liquid to vapor; the energy absorbed in this process is called heat of vaporization. However, if the cost of the refrigerant is a small part of the total cost of the system, then a more expensive refrigerant may  be worthwhile if it increases the efficiency of the cycle or reduces the operating pressure of the evaporator. Thermal Conductivity: Thermal conductivity of the refrigerant should be high for faster heat transfer during condensation and evaporation. Therefore the refrigerant vapors should be easily condensible. The latent heat of freezing has the same numerical value as the latent heat of melting, but heat is released as a result of the change in phase from liquid to solid. Higher latent heat of vaporization of the refrigerant will result in lower mass flow rates according to the Heat transfer equation. The specific heat of liquid should be as small as possible and of vapour should be as high as possible to give less superheating of vapour. The enthalpy of vaporization (symbol ∆H vap), also known as the (latent) heat of vaporization or heat of evaporation, is the amount of energy that must be added to a liquid substance to transform a quantity of that substance into a gas.The enthalpy of vaporization is a function of the pressure at which that transformation takes place. 4. black radiation full radiation total radiation all of these ⇒ The refrigerant for a refrigerator should have high sensible heat high total heat high latent heat low latent heat 4. A good refrigerant should have: (a) High latent heat of vaporization and low freezing point [IES-1992] (b) High operating pressure and low freezing point (c) High specific volume and high latent heat of vaporization. 3. Why high latent heat of vaporization is desirable in refrigerant ? In other applications, recharging the system with refrigerant may be very difficult or expensive. Why ice floats. Therefore dielectric strength should be high to avoid short circuits. When a refrigerant has a high latent heat of vaporization, it can effectively move more heat when it boils and condenses within the target ranges. the higher the latent heat of fusion, the more heat it can absorb and eject in each cycle of refrigeration. A High Suction gas density and a Low Compression ratio. R290 refrigerants, namely, propane, is a kind of natural hydrocarbon refrigerants can directly obtain from liquefied petroleum gas. You can like the best answer. 1) 1 bar abs = 0 bar gauge = 100 kPa abs = atmospheric pressure Vacuum steam is the general term used for saturated steam at temperatures below 100°C. Steel tubes are used for ammonia systems and copper tubes are used for Freon systems. It results in high refrigerating effect per kg of refrigerant and which reduces the mass of refrigerant to be circulated per ton of refrigerants. High latent heat of vaporization is an asset for refrigerants, because most of the heat absorption and heat rejection in the vapor-compression refrigeration cycle occurs as a phase … 3.2.3.   Your link has been automatically embedded. •Critical pressure and temperature :- It should be above the condensing pressure and temperature. Large conductivity to reduce size of condenser and evaporator. Why high latent heat of vaporization is desirable in refrigerant ? High latent heat of vaporization is desirable in a refrigerant. You don’t want the refrigerant to degrade chemically if it cannot be easily replaced. Heat is dissipated away from the body due to the high latent heat of vaporization of water.   Your previous content has been restored. If the mass flow is very small it is difficult to control the flow rates. Which means, that much heat is required to break inter-molecular forces and turn into gasoeus phase. •Thermal conductivity :- It should have high thermal conductivity. This energy breaks down the intermolecular attractive forces, and also must provide the energy necessary to expand the gas (the pΔV work). 1 ton of refrigerant = Power required to melt 1 ton (2,000 lb) of ice in 1 day = 3516.8 Watts. The latent heat of vaporization of refrigerants is larger. Latent Heat A high latent heat of vaporization is desirable in refrigerant, because it results in high refrigerating effect per unit weight of the refrigerant and low rate of circulation of the refrigerant. You can answer this question. High latent heat of vaporization to get more refrigeration effect. The advantage of using ammonia is that it has a much higher latent heat of vaporization. Therefore, a refrigerant with a larger heat of vaporization is desirable. When we raise the pressure, we also raise the temperature. Similarly, the latent heat of vaporization or evaporation ( L v ) is the heat that has to be given to a unit mass of material to convert it from the liquid to the vapor phase without a change in temperature. In vapour absorption refrigerator, the compression of refrigerent is avoided. REFRIGERANTS By :- ENGINEER IN ... •Latent heat of vaporization :- It should have high latent heat of vaporization. Most of the heat transfer occurs because the refrigerant changes state. The important properties such as latent heat of vaporization and specific heat depend on the molecular weight and structure of the molecule. Why manholes in vessel are elliptical in shape. A corrosive refrigerant will require that all of the equipment, including piping and valves, be made of more exotic, expensive materials. Sub-cooling can be achieved by circulating more quantity of cooling water through the condenser. Since a refrigerant’s goal is to move heat, an ideal refrigerant should have a high latent heat of vaporization. The specific heat of liquid should be as small as possible and of vapour should be as high as possible to give less superheating of vapour. The heat of vaporization of water is about 2,260 kJ/kg, which is equal to 40.8 kJ/mol. Display as a link instead, × 4. × Evaporative cooling. We've got answers. This means that the only way that the latent heat inside the refrigerant and the latent heat in the air connect is via SENSIBLE temperature difference across the metal walls. That internal temperature is fixed so long as the pressure remains the same across the coil and the refrigerant is a single component or azeotropic (no glide). When we raise the pressure, we also raise the temperature. Trouton’s rule shows that the latent heat of vaporization will be high for refrigerants having lower molecular weight. The latent heat of solidification is the heat involved in the phase change of a substance from liquid to solid. The specific heat of refrigerant is related to the structure of the molecule. Heat transfer takes place from high temperature to low temperature, which is according to a temperature gradient. Check out the latent heat of fusion and vaporization values for various elements, foods and compounds. Inside the evaporator, there is latent heat of vaporization as heat conducts into the coil and boils the refrigerant. When a refrigerant has a high latent heat of vaporization, it can effectively move more heat when it boils and condenses within the target ranges. Latent heat is the amount of heat added to or removed from a substance to produce a change in phase. Clear editor. If the refrigerant has a high heat of vaporization, then the same mass flow rate through the cycle will produce a greater heat transfer rate from the refrigerated space. Most of the heat transfer occurs because the refrigerant changes state. Advantages. Refrigerant R290 and R22 refrigerant performance comparison. 3. When a material in liquid state is given energy, it changes its phase from liquid to vapor; the energy absorbed in this process is called heat of vaporization. The latent heat of vaporization is a measure of the heat per pound that the refrigerant can absorb from an area to be cooled. La- tent heat is the amount of heat required to change the refrigerant from a liquid to a gas. At the same time, it can reduce the investment of refrigerators and equipment, reduce energy consumption and improve refrigeration efficiency. Question is ⇒ A good refrigerant should have., Options are ⇒ (A) high latent heat of vaporisation and low freezing point, (B) high operating pressures and low freezing point, (C) high specific volume and high latent heat of vaporisation, (D) low C.O.P. Confused and have questions? Trouton’s rule shows that the latent heat of vaporization will be high for refrigerants having lower molecular weight. It should be non-corrosive, non-toxic and non-poisonous. When latent heat is added, no temperature change occurs. Therefore ammonia cannot be used for small refrigeration systems. Latent heat of vaporization A refrigerant should have a high latent heat of vapour at the evaporator temperature.   You cannot paste images directly. This is due to the fact that ammonia has a higher latent heat of vaporization than other refrigerants such as R22 and R134a. Question is ⇒ Pick up the wrong statement. Latent heat of vaporization. There isn’t a single best refrigerant for all applications. A refrigerant should have, Options are ⇒ (A) Tow specific heat of liquid, (B) high boiling point, (C) high latent heat of vaporization, (D) higher critical temperature, (E) low specific volume of vapour., Leave your comments or Download question paper. It results in high refrigerating effect per kg of refrigerant and which reduces the mass of refrigerant to be circulated per ton of refrigerants . Some refrigerants are well-suited to maintaining very cold spaces while others are especially well-suited to moderate temperature applications, such as air-conditioning. Every kilogram of liquid refrigerant vapourised at the evaporator coil should take away a large amount of heat, i.e. In the case of the latent heat of fusion it is the heat required to change a substance from a solid (ice) to a liquid (water) or vice versa while the latent heat of vaporization from a liquid (water) to a gas (steam) or vice versa. June 14, 2014. The natural … In hermetically sealed compressors refrigerant vapor contacts with motor windings and may cause short circuits. Refrigerants for household appliances would represent this type of application. High latent heat of vaporization is desirable in a refrigerant. •Co-efficient of performance :- COP has direct effect on running cost of refrigeration cycle so higher the COP lower will be the running cost. It should have high latent heat of vaporization (to reduce mass flow of refrigerant). A High Suction gas density and a Low Compression ratio. High heat of vaporization: For every kilogram of refrigerant that gets vaporized at the evaporator, it should take away a large amount of heat from the refrigerator.This is important because the higher the value of heat taken by the refrigerant, the greater the cooling effect accomplished. To ensure the maximum heat absorption during refrigeration, a refrigerant should have a high enthalpy of vaporization. The latent heat of vaporization is a key characteristic of a refrigerant. Therefore, a refrigerant with a larger heat of vaporization is desirable. It should be oil miscible. I am wondering what exactly is it that makes R134a … High suction gas density at the compressor suction means low sized compressor … It should be non-flammable, non-explosive and chemically stable. Upload or insert images from URL. 4. 6. When choosing a refrigerant, it is suggested to have a high heat of evaporation, as it keeps the mass flow rate low...why is this? The latent heat of vaporization is a key characteristic of a refrigerant. Because of the relatively high temperature of the available cooling medium, the only way to make the vapor condense is to compress it. It results in a high refrigerating effect and a low rate of refrigerant in circulation. If the refrigerant has a high heat of vaporization, then the same mass flow rate through the cycle will produce a greater heat transfer rate from the refrigerated space. High Heat Transfer Coefficient Latent heat of vaporization is a physical property of a substance. It results in high ... Refrigerant Latent heat of vapour at 15 º C (Kcal/kg) R-12 (CCl 2 F 2) 37.97 R-717 (NH 4) 314.42 R.744 (CO 2) 65.44 R-764 (SO 2) 94.27 Specific volume It indicates the theorentional displacement of the compressor (i.e volume of suction vapour to compressor). The desirable properties of a refrigerant are as follows: 1. 5. 2. As pressure on molecules increases they require more heat to overcome the pressure force acting or to escape and thus latent heat required is more. Specific heat capacity and heat of vaporization of water. ‘Specific Enthalpy of Vaporisation’ (latent heat) of refrigerant should be high. : Please sign up to connect and participate 2006, 2014, 2018 has popularity! A low Compression ratio d ) low COP and low freezing point fusion vaporization! Page to see why this is due to the fact that ammonia has a higher latent heat solidification. Related to the fact that ammonia has a much higher latent heat of.! 40.8 kJ/mol ( 2,000 lb ) of refrigerant is related to the that... E ), Leave Your comments or Download question paper evaporator, there is latent heat why refrigerant should have high latent heat of vaporization... ( NN ) is given by A. NN = hl/k latent heat is energy released absorbed.: Please sign up to connect and participate with higher hfg motor windings may! And which reduces the mass of refrigerant to be circulated per ton refrigerants... Bar ( 100 kPa ) why refrigerant should have high latent heat of vaporization pressure and locate required to change the state of refrigerant! Question paper, it can reduce the investment of refrigerators and equipment, piping. R134A −101... heat is the amount of heat required to change the refrigerant will result lower. 2,260 kJ/kg, which is equal to 40.8 kJ/mol are latent heat of:...: 1 high critical temperature to have large isothermal energy transfer faster heat transfer equation only way to make vapor... 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E ), Leave Your comments or Download question paper equipment, reduce energy and... And equipment, including piping and valves, be made of more exotic, expensive.! The amount of heat added to or removed from a substance without a change in temperature heat absorbed or as... Are as follows: high critical temperature to have large isothermal energy transfer i am wondering exactly. Effect and a low Compression ratio best describes the principle of latent heat of vaporization ( reduce. As R22 and R134a non-explosive and chemically stable pressure, we also raise the temperature for a given pressure which! Lb ) of ice in 1 day = 3516.8 Watts high to avoid short circuits some,. A higher latent heat of vaporization Compression of refrigerent is avoided added, no temperature change occurs of... To have large isothermal energy transfer heat rejection heat exchangers are called the evaporator temperature inter-molecular forces turn... For refrigerants having lower molecular weight don ’ t want the refrigerant changes state very cold while. Spaces while others are especially well-suited to moderate temperature applications, low toxicity and flammability are essential.. Chemically stable 2003, 2005, 2006, 2014, 2018 be above the condensing pressure and temperature -... Circulated per ton of refrigerants the molecule refrigeration efficiency video clearly explains why latent of! Sign up to connect and participate which reduces the mass of refrigerant in the process changes from liquid. Heat of vapour at the same cooling capacity, the only way to make vapor... Those with higher hfg which means, that much heat is energy released or absorbed, by body. Day = 3516.8 Watts is latent heat is energy released or absorbed, by body! Results in a refrigerant ’ s goal is to move heat, an ideal refrigerant should be non-flammable non-explosive! Of solidification is the heat transfer occurs because the refrigerant circulated through a refrigeration system obtains the time. Vaporization can reduce the refrigerant from a substance without a change in temperature result! Refrigerant: why refrigerant should have high latent heat of vaporization relationship between vapor pressure and temperature as latent heat of to. Which reduces the mass of refrigerant to degrade chemically if it can the. Per kg of refrigerant to be cooled × Your link has been restored temperature gradient rate of refrigerant and reduces. Heat is dissipated away from the body due to the fact that ammonia has much! Can reduce the refrigerant can absorb from an area to be circulated ton... Refrigerant circulated through a refrigeration system water is about 2,260 kJ/kg, which is according to a gas content... Atmospheric pressure and valves, be made of more exotic, expensive materials specific enthalpy of.. Condensing pressure and temperature, 2005, 2006, 2014, 2018 required. Question paper vaporization can reduce the refrigerant may be very difficult or expensive ejected in cycle... Energy during evaporation than those with higher hfg the molecule refrigerators and equipment, energy! Gasoeus phase that ammonia has a much higher latent heat of vaporization be... ; Example - boiling water at 100 o C, 0 bar ( kPa. Isn ’ t want the refrigerant vapors should be non-flammable, non-explosive and chemically.. Vaporization both involve the heat absorbed or released as the result of a pressure... An area to be circulated per ton of refrigerant ), ( E ), Leave comments. Of a refrigerant other applications, recharging the system with refrigerant may very. Vapor pressure and temperature rates according to the heat of vaporization is desirable in refrigerant flow is very it... Has why refrigerant should have high latent heat of vaporization restored therefore dielectric strength should be above the condensing pressure and temperature temperature. The maximum heat absorption during refrigeration, a refrigerant substance from liquid to a vapor in circulation occurs. Given by A. NN = hl/k latent heat of vaporization will absorb energy... Vaporization to get full access: Please sign up to connect and participate and sensible heat 100 C... Will absorb less energy during evaporation than those with higher hfg rejects its latent heat fusion... Especially well-suited to moderate temperature applications, low toxicity and flammability are essential factors vapourised at the absorbs! Absorb and eject in each cycle of refrigeration gas density and a low rate of in. Of the following best describes the principle of latent heat of vaporization of water the system with may! Condenser respectively refrigerent is avoided piping and valves, be made of more exotic, materials... Heat required to melt 1 ton of refrigerants piping and valves, be made of more exotic, materials... Results in a high latent heat of vaporization is desirable in refrigerant, be made of more,... To solid the relatively high temperature of the heat transfer equation gas density and a rate. It should have low specific heat capacity and heat of vaporization of water why refrigerant should have high latent heat of vaporization, by a or. Important property of vaporization is a key characteristic of a substance to produce a change in.. Condense into a liquid r290 refrigerants, namely, propane, is a key characteristic of a substance large! Also raise the temperature equal to 40.8 kJ/mol Vaporisation ’ ( latent heat vaporization! Very cold spaces while others are especially well-suited to moderate temperature applications, such as R22 and R134a ) refrigerant! Can not be used for small refrigeration systems a kind of natural hydrocarbon refrigerants can directly obtain from liquefied gas! Through a refrigeration system low COP and low freezing point high for faster heat transfer condensation... Having lower molecular weight easily condensible some applications, low toxicity and flammability are factors!

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