Category: Refrigeration And Air Conditioning

Advantages Disadvantages

Heat extracted from system (i.e., absorbed in absorber) = Heat transfer during the process, A−B = refrigerating effect. Heat rejected from condenser

Advantages Disadvantages Example 8.1: Carnot refrigeration cycle absorbs heat at 250 K and rejects heat at 300 K. Solution: Given: T1 = 250 K; T2 = 300 K Example 8.2: The capacity of a refrigerator is 150 TR when working between − 5 and 20°C. Determine the mass of ice produced per day from water at 20°C. Also find the power… Continue reading Advantages and Disadvantages of Air-refrigeration System

In this system, air is taken into the compressor from atmosphere and compressed and then the hot compressed air is cooled in heat exchanger up to the atmospheric temperature. The cooled air is then expanded in an expander. The temperature of the air coming out from the expander is below the atmospheric temperature due to… Continue reading Bell–Coleman Cycle or Reversed Brayton Cycle

Reversed Carnot cycle Reversed Carnot cycle is shown in Figure 8.2. It consists of the following processes. Figure 8.2 P−V and T−S Diagrams for Reversed Carnot Cycle Process a–b: Absorption of heat by the working fluid from refrigerator at constant low temperature TL during isothermal expansion. Process b–c: Isentropic compression of the working fluid with the aid of external work. The temperature of the fluid… Continue reading Air-refrigeration System

Broadly, the refrigeration systems can be categorized as

Within the refrigeration system, the expansion valve is located at the end of the liquid line, before the evaporator. The high-pressure liquid reaches the expansion valve, having come from the condenser. The valve then reduces the pressure of the refrigerant as it passes through the orifice, which is located inside the valve. On reducing the… Continue reading Expansion Valve

The purpose of the condenser is to extract heat from the refrigerant to the outside air. The condenser is usually installed on the reinforced roof of the building, which enables the transfer of heat. Fans mounted above the condenser unit are used to draw air through the condenser coils. The temperature of the high-pressure vapour… Continue reading Condenser

The purpose of the compressor is to draw the low-temperature, low-pressure vapour from the evaporator via the suction line. Once drawn, the vapour is compressed. When vapour is compressed it rises in temperature. Therefore, the compressor transforms the vapour from a low-temperature vapour to a high-temperature vapour, in turn increasing the pressure. The vapour is… Continue reading Compressor