Design of shell and tube heat exchanger for air conditioning-water heating hybrid system

Abstract EN

The use of air conditioning-water heating hybrid system for heating, cooling and hot water of buildings, has significantly importance for energy saving.

It has been proposed a system to recover the waste heat of refrigerant after leaving the air conditioning system condenser in the heating mode and the waste heat of refrigerant after leaving the air conditioning system compressor in the cooling mode to heat water for domestics or other needs.

Shell and tube heat exchanger has been designed as a refrigerant-to-water heat exchanger located between the condenser and the expansion valve in the heating mode and between the compressor and the condenser in the cooling mode.

The simulation program of heat exchanger has been built by using (MATLAP) in order to determining the heat transfer parameters and the temperature difference between the inlet cold water and outlet hot water, the results show that the effectiveness decrease with increase of water mass flow rate, while increase with increase of tube length.

As the tube length (15) m, the outlet hot water temperature from heat exchanger is (60.94) °C, for water mass flow rate (0.15) kg/s, and this value decrease exponentially and reach to about (7.528) °C, for water mass flow rate (2) kg/s, while for tube length (5) m, these values ranging between (43.92) °C, to (1.234) °C, respectively