Sadi Carnot, in 1824, explained mathematical principle of refrigeration operation. It was described as a heat engine. In the process of vapor compression refrigeration the refrigerant has to complete phases in cyclic order. In this process, heat is removed and consequently the desired location becomes cool. It is a mechanical process. Indeed, refrigeration system is the process of several refrigeration cycles. It is the widely exploited method for various purposes such as refrigeration, air-conditioning of surrounded places, and vehicles. The method is used in domestic and commercial purposes as well. Storing foods and meats the process is much eligible and is used in large scale. Several offices and technical fields utilize the method of refrigeration
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This method implies a process of eliminating heat from a substance. After heat removing, the next stage of the refrigeration process is to pass it out elsewhere in order to fulfill the desired purpose of lessening temperature of that particular place or space. Another aim is to maintain a desired lower temperature. According to the Second Law of Thermodynamics, heat does not pass from the cold place to warm place without the assistance of an outer agent. Therefore, a refrigerator needs to have an outer agent to operate it smoothly. The usual refrigeration process comprises the compressor’s input of work and exploits the vapor density cycle. Such technique is described in Figure 1. There are four fundamental elements of the cycle of vapor density refrigeration:
1. Evaporator. This element presupposes the maintenance of low pressure. Thus, heat could be absorbed to boil the fluid at a low temperature.
2. Compressor. This element works in order to minimize pressure elimination from the system into the evaporator (sucking in low-pressure, low-temperature saturated vapor). Moreover, it reduces high temperature and pressure vapor that enter the condenser.
3. Condenser. This element decreases the high superheated and saturated temperature and high pressure. Therefore, the heat also decreases due to the temperature drop. Thus, it returns to liquid state …show more content…
Energy transfer in a refrigeration system.
Coefficient of performance of a refrigerator is the ratio of:
The method of plotting P-h cycle diagram:
1. By noting the following procedures, the P-h cycle diagram can be plotted:
(i) Condensing pressure, ( ).
(ii) Evaporator pressure, ( ).
(iii) Temperature of the refrigerant at compressor suction/outlet from evaporator, ( ).
(iv) Temperature of the refrigerant at compressor delivery/inlet to the condenser, ( ).
(v) Temperature of the refrigerant leaving the condenser,
2. To locate the state points on the P-h diagram, as illustrated in Figure 9, proceed as follows:
(i) Point 1 is marked at the intersection of and t1 (in the superheated region).
(ii) Point 2 is situated at the intersection of and t2 (in the superheated region).
(iii) From point 1 draw a curve following constant entropy curves, or draw parallel to nearby constant entropy curves.
(iv) Point 3 is positioned by the intersection of ( ) and ( ).
(v) Point 4 is located by dropping a vertical line from point 3 to the intersection with the
This method implies a process of eliminating heat from a substance. After heat removing, the next stage of the refrigeration process is to pass it out elsewhere in order to fulfill the desired purpose of lessening temperature of that particular place or space. Another aim is to maintain a desired lower temperature. According to the Second Law of Thermodynamics, heat does not pass from the cold place to warm place without the assistance of an outer agent. Therefore, a refrigerator needs to have an outer agent to operate it smoothly. The usual refrigeration process comprises the compressor’s input of work and exploits the vapor density cycle. Such technique is described in Figure 1. There are four fundamental elements of the cycle of vapor density refrigeration:
1. Evaporator. This element presupposes the maintenance of low pressure. Thus, heat could be absorbed to boil the fluid at a low temperature.
2. Compressor. This element works in order to minimize pressure elimination from the system into the evaporator (sucking in low-pressure, low-temperature saturated vapor). Moreover, it reduces high temperature and pressure vapor that enter the condenser.
3. Condenser. This element decreases the high superheated and saturated temperature and high pressure. Therefore, the heat also decreases due to the temperature drop. Thus, it returns to liquid state …show more content…
Energy transfer in a refrigeration system.
Coefficient of performance of a refrigerator is the ratio of:
The method of plotting P-h cycle diagram:
1. By noting the following procedures, the P-h cycle diagram can be plotted:
(i) Condensing pressure, ( ).
(ii) Evaporator pressure, ( ).
(iii) Temperature of the refrigerant at compressor suction/outlet from evaporator, ( ).
(iv) Temperature of the refrigerant at compressor delivery/inlet to the condenser, ( ).
(v) Temperature of the refrigerant leaving the condenser,
2. To locate the state points on the P-h diagram, as illustrated in Figure 9, proceed as follows:
(i) Point 1 is marked at the intersection of and t1 (in the superheated region).
(ii) Point 2 is situated at the intersection of and t2 (in the superheated region).
(iii) From point 1 draw a curve following constant entropy curves, or draw parallel to nearby constant entropy curves.
(iv) Point 3 is positioned by the intersection of ( ) and ( ).
(v) Point 4 is located by dropping a vertical line from point 3 to the intersection with the