Basic principle of regenerative heat exchanger
The regenerative heat exchanger transfers heat from one fluid to another through the short-term energy storage of the porous filler or matrix. First, during the time conventionally referred to as the heating cycle, the hot gas flows through the packing in the regenerative heat exchanger, and heat is transferred from the gas stream to the packing, and the gas stream temperature is lowered. At the end of this cycle, the flow direction is switched and the cold fluid flows through the regenerator. During the cooling cycle, the fluid absorbs heat from the heat storage packing. Therefore, for the conventional flow direction change, the filler in the heat storage body alternately exchanges heat with the hot and cold fluid, and the temperature in the heat storage body and the gas flow at any position constantly fluctuates with time. After startup, after several switching cycles, the regenerative heat exchanger enters a stable operation state, and the fluctuation of a certain position in the regenerative body with time is the same in successive cycles. It is easy to distinguish between the regenerative heat exchanger and the recuperative heat exchanger from the characteristics of operation. The heat transfer of the two fluids in the recuperative heat exchanger is carried out through the fixed boundary of each position, and is changed during stable operation. The temperature inside the heat exchanger is only related to the position, and the heat transfer in the regenerative heat exchanger is dynamic, depending on the position and time.