The plate heat exchanger is composed of a set of metal corrugated plates. The four corner holes on the board allow the cold and hot media to pass through. The reduced resistance of the plate heat exchanger has the advantages of increasing the heat transfer coefficient and increasing the average flow rate of the medium in the flow channel between the plates. Generally speaking, when the resistance is reduced, the power consumption of the circulating pump and the equipment cost will be increased. So what are the methods for reducing the resistance drop of the plate heat exchanger?
(1) The use of a heat mixing plate can reduce the plate area than a symmetrical single-process heat exchanger. Thermal mixing plate design technology is difficult to achieve accurate matching will lead to limited plate area saving. Therefore, it is not suitable to use a hot mixing plate when the flow of cold and heat medium is relatively large.
(2) When the flow of cold and hot media is large, a multi-process combination arrangement is adopted.
(3) Asymmetric plate heat exchanger. A plate heat exchanger with equal cross-sectional areas of cold and hot runners is formed. According to the heat transfer characteristics and pressure drop requirements of the cold and hot fluids, the symmetrical plate heat exchanger is composed of plates with the same corrugated geometry on both sides of the plate. When the heat and cold medium flow ratio is large, the use of an asymmetric single-process heat exchanger can reduce the plate area by 15%-30% compared to a symmetrical single-process heat exchanger.
(4) Set a bypass pipe for the heat exchanger. When the flow of cold and heat medium is relatively large, a bypass pipe can be installed between the inlet and outlet of the heat exchanger on the side of the large flow. The bypass pipe of the heat exchanger can ensure the heat exchanger has a higher heat transfer coefficient and reduce the resistance of the heat exchanger.