Dry compression

Dry compression

by

1 Answer

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 dry saturated or slightly superheated. Then the entire compression will take place in the superheated region such type of compression is known as dry compression. 

Wet compression- Wet compression is the case where some liquid portion of refrigerant enters the compressor along with vapour part of refrigerant before compression.

Effect of wet compression on compressora) The liquid form of refrigerant enters into the compressor it will washers away the lubricant inside the compressor and leads to damage of compressor. b) Compressor blade erosion due to impingement of water droplets. c) liquid droplet mix with lubricating oil and pass to condenser and decrease heat transfer rate from refrigerant to condensing medium. d) C.O.P.is lower for the entire system. so it's always preferred to go for dry compression. 
by

Related questions

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. 

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.

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.

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. 

Desirable properties of refrigerant.

Description : Desirable properties of refrigerant.

Last 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 ... k) It should have high thermal conductivity. l) It should have chemical stability.

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.

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.

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 advantage of dry compression is that (a) it permits higher speeds to be used (b) it permits complete evaporation in the evaporator (c) it results in high volumetirc and mechanical efficiency (d) all of the above

Description : The advantage of dry compression is that (a) it permits higher speeds to be used (b) it permits complete evaporation in the evaporator (c) it results in high volumetirc and mechanical efficiency (d) all of the above

Last Answer : Ans: d

In vapour compression cycle the condition off refrigerant is dry saturated vapour (a) after passing through the condenser (b) before passing through the condenser (c)before entering the expansion valve (d) before entering the compressor

Description : In vapour compression cycle the condition off refrigerant is dry saturated vapour (a) after passing through the condenser (b) before passing through the condenser (c)before entering the expansion valve (d) before entering the compressor

Last Answer : Ans: D