Desirable properties of refrigerant.

Desirable properties of refrigerant.
by

1 Answer

Answer :

a) Boiling point at atmospheric pressure should be low.

b) Freezing point at atmospheric pressure should be low.

c) Latent heat of vaporization of refrigerant must be high.

d) Critical temperature should be high.

e) It should not have corrosive action with system material.

f) It should not be flammable & explosive.

g) It should not be toxic.

h) It leak should be easily detectable.

i) It should have positive condensing pressure.

j) It should have satisfactory heat transfer coefficient.

k) It should have high thermal conductivity.

l) It should have chemical stability.


by

Related questions

Which of the following is not a desirable property of a refrigerant (a) highmisibility with oil (b) low boiling point (c) good electrical conductor (d) large latent heat

Description : Which of the following is not a desirable property of a refrigerant (a) highmisibility with oil (b) low boiling point (c) good electrical conductor (d) large latent heat

Last Answer : Ans: c

Why high latent heat of vaporisation is desirable in a refrigerant ?

Description : Why high latent heat of vaporisation is desirable in a refrigerant ?

Last Answer : A high latent heat of vaporisation of refrigerant results in small amount of refrigerant and thus lesser circulation system of refrigerant for same tonnage.

Properties of Insulating Material

Description : Properties of Insulating Material

Last Answer : i. Thermal conductivity: Thermal conductivity of insulating material should be as possible to reduce the thickness of material. ii. Nonflammable: Insulating material should be fire proof and nonflammable ... and should available easily. v. Strength vi. Chemical Stability. vii. Moisture Resistance.

What Are The Desirable Properties Of A Coolant?

Description : What Are The Desirable Properties Of A Coolant?

Last Answer :  It should not absorb neutron  Have high chemical and radiation stability  Non-corrosive  Have high boiling point  Non-toxic

What Are The Desirable Properties Of A Good Moderator?

Description : What Are The Desirable Properties Of A Good Moderator?

Last Answer :  It must be as light as possible It must slow down the neutron as quick as possible.  It must have resistance to corrosion.  It must have good machinability.  It must have good conductivity and high melting point.

State the functions of a fuse. Mention the desirable properties of fuse materials.

Description : State the functions of a fuse. Mention the desirable properties of fuse materials.

Last Answer : Ans: Fuse is a protective device, which consists of a thin wire or strip. This wire or strip is placed with the circuit it has to protect, so that the circuit-current flows through it. When ... silver and silver alloys are used of lower ratings. Copper alloys are used in fuses of higher ratings.

Which of the following properties is not necessarily desirable in the material for transformer core? A. Mechanical strength B. Low hysteresis loss C. High thermal conductivity D. High permeability

Description : Which of the following properties is not necessarily desirable in the material for transformer core? A. Mechanical strength B. Low hysteresis loss C. High thermal conductivity D. High permeability

Last Answer : C) high thermal conductivity

List desirable properties of hydraulic oil.

Description : List desirable properties of hydraulic oil.

Last Answer : Following are the main Properties of hydraulic oil required to fulfill its functions: 1) Stable viscosity characteristics 2) Good incompressibility (High bulk modulus) 3) Good lubricity ... rust and corrosion preventive qualities 9) Minimum toxicity 10) Ready availability and inexpensive

List properties desirable for spring material

Description : List properties desirable for spring material

Last Answer : 1)High Resilience 2) High ductile 3)High static strength 4) High fatigue strength 5) Non corrosive

desirable properties of Cable

Description : desirable properties of Cable

Last Answer : Following are the main properties of cables:  1. Stranded Conductor: The conductor used for cable should be stranded specially for large size of cable because,  To increase the flexibility ... and mechanical injury.  7. Life: The material used for cable should have long life. 

State desirable properties of heating elements used in indirect resistance heating.

Description : State desirable properties of heating elements used in indirect resistance heating. 

Last Answer : Following properties of good heating material in indirect resistance heating:- 1. High resistivity: It should have high resistivity. So that it becomes compact in size and produces more heat with small ... , it should have low temperature co-efficient of resistance. 10.It should not be brittle.

The desirable properties of transformer core material are

Description : The desirable properties of transformer core material are  (1) low permeability and low hysteresis loss. (2) high permeability and high hysteresis loss. (3) high permeability and low hysteresis loss. (4) low permeability and hysteresis loss.

Last Answer : The desirable properties of transformer core material are high permeability and low hysteresis loss.

winter air conditioning

Description : winter air conditioning

Last Answer : In winter air conditioning, the air is heated which is generally followed by humidification. The schematic arrangement of the system is shown in Fig. The outside air flows through a damper ... loss of conditioned (or used) air through exhaust fans or ventilation from the conditioned space. 

Industrial application of refrigeration

Description : Industrial application of refrigeration

Last Answer : Air-conditioning for comfort of workers For textile industries for production of quality textile products. For manufacturing process in photographic industry. In printing industries ... devices test gauges and precision gears etc. where close tolerance of dimensions is required.

Working of domestic refrigerator

Description : Working of domestic refrigerator

Last Answer : Domestic Refrigerator : The internal parts of the refrigerator are ones that carry out actual working of the refrigerator. Some of the internal parts are located at the back of the refrigerator, and ... button or there is automatic system comprising of the electric heater and the timer.

Classify chiller and it application

Description : Classify chiller and it application

Last Answer : There are three different types of chillers: (1) air (2) water (3) evaporative condensed chiller Industrial chillers: (1) reciprocating, (2) centrifugal, (3) screw ... quality waste heat or cheap heat. They are often found in hospitals and buildings with heated swimming pools.

Working of evaporative type condenser

Description : Working of evaporative type condenser

Last Answer : Working of evaporative type condenser: Evaporative condensers combine the features of a cooling tower and water-cooled condenser in a single unit. In evaporative condensers, both air and water are used to extract ... The role of air is primarily to increase the rate of evaporation of water. 

Working of centrifugal compressor

Description : Working of centrifugal compressor 

Last Answer : Working of centrifugal compressor : When the air passes through the rotating impeller it experiences force or work which is performed by centrifugal forces. The work input takes place as an increase in ... about 65% and 35% of the total pressure developed or produced in the compressor.

Following factors are affecting on human comfort.

Description : Following factors are affecting on human comfort. 

Last Answer : 1. Temperature of air: In air conditioning, the control of temperature means the maintenance of any desired temperature within an enclosed space even though the temperature of the outside air is ... necessary that there should be equi-distribution of air throughout the space to be air conditioned. 

Dry compression

Description : Dry compression

Last Answer : Dry compression- Dry compression means completely dry vapour form of refrigerant enters the compressor before compression. In this removal of heat during evaporation process should be continued till the vapour gets ... lower for the entire system. so it's always preferred to go for dry compression. 

Vortex tube refrigeration

Description : Vortex tube refrigeration

Last Answer : Vortex tube refrigeration Working: - Vortex tube is simple device of producing cold. A compressed air is passed tangentially through nozzle. Here air velocity increases due to expansion and ... the diaphragm hole into the cold side, while hot stream is passed through the opening valve.

Hermetic sealed compressor

Description : Hermetic sealed compressor

Last Answer : Hermetic sealed compressor: A hermetic sealed compressor is one in which both compressor and motor are confined in a single outer welded steel shell. The motor and compressor are directly coupled ... sealed compressors have very long life. 7) The leakage of refrigerant is completely avoided.

Effect Of Superheating of suction Vapour-(before compression)

Description : Effect Of Superheating of suction Vapour-(before compression)

Last Answer : Effect Of Superheating of suction Vapour-(before compression) A vapour compression cycle with superheated vapour before compression is shown on T-s and p-h diagrams respectively. In this cycle, the ... . Thus, to avoid this, a 5 to 20 K superheat of the refrigerant is always desirable. 

Global Warming

Description : Global Warming

Last Answer : Global Warming: It is also affects on climate. It refers to the long term fluctuations in Temperature, precipitation, wind and earth elements of the earth climate system. The effects of global warming ... Changes (IPCC) projects increase in average global temperatures ranging from 1.4 0C to 5.8 0C

Green House Effect

Description : Green House Effect

Last Answer : Green House Effect:- It is earth ability to retain heat. When the sun rays reach the planet, approximately two thirds of the thermal energy enters earth's atmosphere and is absorbed by the planet's ... would be nearly 35°C (63°F) colder, and the planet would be much less suitable for human life.

Would using an old refrigerator that takes blocks of Ice as the refrigerant be better for any reason?

Description : Would using an old refrigerator that takes blocks of Ice as the refrigerant be better for any reason?

Last Answer : Energy is still used. That ice has to come from somewhere and then it has to be delivered.

Who does online testing for Refrigerant CFC certicate?

Description : Who does online testing for Refrigerant CFC certicate?

Last Answer : Need Answer

What is the best refrigerant gas?

Description : What is the best refrigerant gas?

Last Answer : Best refrigerant gas is R-290 and R600A because of its low environmental impact and excellent thermodynamics performance.

Is freon Refrigerant Harmful to the environment?

Description : Is freon Refrigerant Harmful to the environment?

Last Answer : Of course it is . Freon is a chlorofluorocarbons that causes depletion of ozone.Freon contains number of halo products like chlorine ,hydrogen bromine etc. Refrigerators are powerful source of these ... house which is causing increased temperature on earth sea level rising .ice depletion etc.

How do i check the refrigerant level of my car AC?

Description : How do i check the refrigerant level of my car AC?

Last Answer : To perfectly check your AC level you need to understand the components that makes up the unit such as compressor, condenser, evaporator. But the simplest method is to check if the air coming out ... use of gauge to check the air pressure from compressor but this needs a more expertise experience.

What is use of refrigerant gas in Air conditioner and in Refrigerator?

Description : What is use of refrigerant gas in Air conditioner and in Refrigerator?

Last Answer : Refrigerants are the common name for the chemical blend that cycles through the AC, changing from liquid to a gas as it absorbs and release heat.

Why must liquid refrigerant be present for the pressure - temperature relationship to apply?

Description : Why must liquid refrigerant be present for the pressure - temperature relationship to apply?

Last Answer : Need answer

What happens If a large amount of lubricant is removed from a system during refrigerant recovery?

Description : What happens If a large amount of lubricant is removed from a system during refrigerant recovery?

Last Answer : the sys has too much lubricant

What sae standards must be referred to on label of approved hfc-134a refrigerant recycling machines?

Description : What sae standards must be referred to on label of approved hfc-134a refrigerant recycling machines?

Last Answer : SAE J2210 or SAE J2788

What EPA rules require capture. of 80 of the refrigerant from a small appliance sealed system with a non-operating comprerssor if technicians are using?

Description : What EPA rules require capture. of 80 of the refrigerant from a small appliance sealed system with a non-operating comprerssor if technicians are using?

Last Answer : Feel Free to Answer

What degrees of superheat does a refrigerant system evaporator run?

Description : What degrees of superheat does a refrigerant system evaporator run?

Last Answer : Feel Free to Answer

If an hfc-134a AC system still has pressure after the first refrigerant recovery process is complete additional recovery is necessary until the system vacuum level remains stable for?

Description : If an hfc-134a AC system still has pressure after the first refrigerant recovery process is complete additional recovery is necessary until the system vacuum level remains stable for?

Last Answer : 5

How come moisture mentioned in SEA J2099 standards of refrigerant purity?

Description : How come moisture mentioned in SEA J2099 standards of refrigerant purity?

Last Answer : What is the answer ?

Where is subcooled refrigerant found?

Description : Where is subcooled refrigerant found?

Last Answer : Need answer

How do you add refrigerant to a Toyota Camry?

Description : How do you add refrigerant to a Toyota Camry?

Last Answer : Need answer

If an hfc-134a AC system still has pressure after the first refrigerant recovery process is complete additional recovery is necessary until the system vacuum level remains stable for?

Description : If an hfc-134a AC system still has pressure after the first refrigerant recovery process is complete additional recovery is necessary until the system vacuum level remains stable for?

Last Answer : 5

Auto air conditioning refrigerant compatibility?

Description : Auto air conditioning refrigerant compatibility?

Last Answer : All air conditioning units use Freon, a chemical that when circulated helps to keep air cool. The kind of freon used in both devices is not the same, and chemical solutions with different amounts of each are needed to get the job done.

In milk chilling plant, the usual secondary refrigerant is (a)ammonia (b)sodium silicate (c) glycol (d) brine

Description : In milk chilling plant, the usual secondary refrigerant is (a)ammonia (b)sodium silicate (c) glycol (d) brine

Last Answer : Ans: d

The condition of refrigerant before entering the expansion or throttle valve, in a vapour compression system (a) dry vapour (b) wet vapour (c)liquid-vapour mixture (d) high pressure saturated liquid

Description : The condition of refrigerant before entering the expansion or throttle valve, in a vapour compression system (a) dry vapour (b) wet vapour (c)liquid-vapour mixture (d) high pressure saturated liquid

Last Answer : Ans: d

The C.O.P. of a refrigeration cycle with lowering of condenser temperature, keeping the evaporator temperatureconstant, will (a) increase (b) decrease (c) may increase or decrease depending on the type of refrigerant used (d) remain unaffected

Description : The C.O.P. of a refrigeration cycle with lowering of condenser temperature, keeping the evaporator temperatureconstant, will (a) increase (b) decrease (c) may increase or decrease depending on the type of refrigerant used (d) remain unaffected

Last Answer : Ans: a

The C.O.P of a refrigeration cycle with increase in evaporator temperature, keeping condenser temperature constant, will (a) increase (b) decrease (c) remain unaffected (d) may increase or decrease depending on the type of refrigerant used

Description : The C.O.P of a refrigeration cycle with increase in evaporator temperature, keeping condenser temperature constant, will (a) increase (b) decrease (c) remain unaffected (d) may increase or decrease depending on the type of refrigerant used

Last Answer : Ans: a

The coefficient of performance is the ratio of the refrigerant effect to the (a) heat of compression (b) work done by compressor (c) enthalpy increase in compressor (d) all of the above

Description : The coefficient of performance is the ratio of the refrigerant effect to the (a) heat of compression (b) work done by compressor (c) enthalpy increase in compressor (d) all of the above

Last Answer : Ans: d

Choose the wrong statement (a) Temperature of medium being cooled must be below that of the evaporator (b) Refrigerant leaves the condenser as liquid (c) All solar thermally operated absorption systems are capable only of intermittent operation (d) frost on evaporator reduces heat transfer

Description : Choose the wrong statement (a) Temperature of medium being cooled must be below that of the evaporator (b) Refrigerant leaves the condenser as liquid (c) All solar thermally operated absorption systems are capable only of intermittent operation (d) frost on evaporator reduces heat transfer

Last Answer : Ans: a

Choose the correct statement (a) A refrigerant should have low latent heat (b) If operating temperature of system is low, then refrigerant with low boiling point should be used (c) Pre-cooling and sub-cooling bf refrigerant are same (d) Superheat and sensible heat of a. refrigerant are same

Description : Choose the correct statement (a) A refrigerant should have low latent heat (b) If operating temperature of system is low, then refrigerant with low boiling point should be used (c) Pre-cooling and sub-cooling bf refrigerant are same (d) Superheat and sensible heat of a. refrigerant are same

Last Answer : Ans: b

For proper refrigeration in a cabinet, if the temperature and vapour pressure difference between cabinet and atmosphereis high, then (a) bigger cabinet should be used (b) smaller cabinet should be used (c) perfectly tight vapour seal should be used (d) refrigerant with lower evaporation temperature should be used

Description : For proper refrigeration in a cabinet, if the temperature and vapour pressure difference between cabinet and atmosphereis high, then (a) bigger cabinet should be used (b) smaller cabinet should ... tight vapour seal should be used (d) refrigerant with lower evaporation temperature should be used

Last Answer : Ans: c