The plate heat exchanger is composed of a set of corrugated metal plates. The holes in the plate are used for the two liquids to pass through. The metal heat exchange plates are installed in a frame with a fixed plate and a movable pressing plate on the side, and are clamped by clamping bolts. The plates are equipped with sealing gaskets to seal the liquid channels and guide the fluid to alternately flow into the respective channels. The heat transfer of the plate heat exchanger directly affects its use effect, so how can the heat transfer coefficient be improved?
(1) The corrugation of the plate heat exchanger can cause the fluid to generate turbulence at a small flow rate, so a higher surface heat transfer coefficient can be obtained. The surface heat transfer coefficient is related to the geometric structure of the plate corrugation and the flow state of the medium. The waveform of the plate includes herringbone, straight, spherical and so on. Herringbone plates with triangular corrugated cross-sections have a higher surface heat transfer coefficient, and the larger the corrugation angle, the higher the flow rate of the medium in the flow channel between the plates, and the greater the surface heat transfer coefficient.
(2) Use heat exchanger plates with high thermal conductivity. The plate material can choose austenitic stainless steel, titanium alloy, copper alloy. Stainless steel has good thermal conductivity, with a thermal conductivity of about 14. 4 W/(m.K), high strength, good stamping performance, and is not easy to be oxidized. The price is lower than that of titanium alloy and copper alloy, but its resistance to chloride ion corrosion is poor.
(3) Reduce the thickness of the heat exchanger plates. The design thickness of the plate has nothing to do with its corrosion resistance, but is related to the pressure bearing capacity of the heat exchanger. When the herringbone plate is combined, the adjacent plates are turned upside down and the corrugations are in contact with each other, forming a fulcrum with high density and uniform distribution.