Methodology Aircon.docx

Methodology The schematic diagram of air conditioning system in a car is shown in figure 1. Just like refrigeration, it uses refrigerant or coolant. The system consists of compressor or engine driven pump, evaporator which gives us the cooling results. The receiver or drier which will absorb moisture (water) that may have gotten inside the A/C system during the cycle. Moisture can get into the A/C components from humidity in the air or ambient air. A cooling fan and blower motor are introduced in condenser and evaporator for the better result. P-h diagram has been shown in figure 2. Figure 3 shows the diagram with solar panel connected to the system. Solar panel will receive light energy and then it will convert to electrical energy.

Figure 1: Schematic diagram of air conditioning system in a car

Figure 2: Pressure-Enthalpy Diagram

Figure 2 shows the diagram of pressure and the enthalpy of a vapor compression cycle. Refrigerant enters the compressor in a vapor phase is saturated at point 1. The refrigerant is compressed adiabatically and becomes superheated steam due to an increase in pressure, temperature and enthalpy as indicated by point 2. Refrigerant at this point is above the temperature of the ambient air. Then, the refrigerant is leaving for the condenser. During the condensers, heat from the refrigerant released into the outside air so that the change of superheated refrigerant into the saturated vapor at the point 2a. Then, the refrigerant condenses into a liquid by releasing the latent heat of condensation. Condensation continues until all the liquid vapor becomes saturated at point 3. From point 3 to point 4, saturated liquid will expand by the use of expansion valve. And again, it will repeat the cycle itself. COP compares the refrigerating effect generating by evaporator to the compressor work. For the COP (Coefficient of performance); Coefficient of Performance (COP) =

Coefficient of Performance (COP) =

𝑁𝑒𝑡 𝑟𝑒𝑓𝑟𝑖𝑔𝑒𝑟𝑎𝑡𝑖𝑛𝑔 𝑒𝑓𝑓𝑒𝑐𝑡 (𝑄𝑎 ) 𝑊𝑜𝑟𝑑 𝑑𝑜𝑛𝑒 𝑏𝑦 𝑡ℎ𝑒 𝑐𝑜𝑚𝑝𝑟𝑒𝑠𝑠𝑜𝑟 (𝑊𝑐 )

ℎ1 − ℎ4 ℎ2 − ℎ1