What is the function of plate heat exchanger in closed cycle cooling water system?

- Mar 08, 2021-

In the closed circulating cooling water system of the plate heat exchanger, the cooling water and the corrugated plates on both sides of the cooling water convection, using herringbone corrugations. These heat transfer plates are corrugated obliquely, that is, the adjacent heat transfer plates have the same inclination angle And the direction is different from the ripple. The cross-sectional area is constant along the flow direction, but changes in the flow direction can cause turbulence.


The corrugation depth of the general heat exchange plate is 3 ~ 5mm, and the flow velocity in the turbulent zone is about 0.1 ~ 1.0m/s. The corrugated plate is very thin and the thickness is 0.5 ~ 1 mm. There are many contact points between adjacent plates. Running under normal pressure, adjacent plates of herringbone grooves have opposite directions, and the intersection of the contact points formed by the two grooves can also eliminate vibration, promote turbulent flow and heat exchange, and at the same time promote the elimination of fatigue fracture and internal leakage.


The herringbone corrugated plate has a high degree of turbulence. High turbulence can fully play a cleaning role and can be particularly effective in reducing the deposited dirt. However, the more contact points of the corrugated plate, the poorer water quality will contain suspended solid particles, clutter and Aquatic plants, due to the very narrow gap between the plates, ensure that all particles larger than 2 mm are filtered out before entering the heat exchanger. If the screen does not function effectively, it is prone to blockage.


For plate heat exchangers, the cooling water side and the cooling water side flow uniformly and in opposite directions. Two turbulent fluids caused by the pulsation effect caused by the high heat transfer rate, high resistance pressure drop and high shear stress field, will Lead to inhibit the formation of fouling on the heat exchange surface. The heat transfer coefficient is generally 5000 ~ 6000w /, saving heat exchange area.


Due to the structural characteristics of the plate heat exchanger, it can be as low as 1 degree in terms of economy. The plate heat exchanger can greatly reduce the amount of cooling water, and the ratio of cooling water to cooling water is 0.8 to 1.1:1. This will reduce the installation and operating costs of pipeline valves and pumps.


The plate heat exchanger has the advantages of small size, light weight, convenient maintenance, no maintenance and lifting facilities, and less installation space. Manual maintenance of the plate heat exchanger includes folding the entire machine, cleaning the plates and gaskets with a spray gun and brush, inspecting the plates and gaskets if necessary, and replacing the plates and gaskets if necessary.