To improve the heat transfer coefficient of the commutation equipment, only by increasing the surface heat transfer coefficient of the hot and cold sides, reducing the thermal resistance of the dirt layer, selecting plates with high thermal conductivity, and reducing the thickness of the plates, can the commutation equipment be effectively improved. the heat transfer coefficient. hook type commutator manufacturers often use the following two methods:
a. Improve the surface heat transfer coefficient of the plate
Since the corrugation of the plate commutation equipment can make the fluid turbulent at a small flow rate (when Reynolds number is 150), it can obtain a higher surface heat transfer coefficient, the surface heat transfer coefficient and the geometry of the plate corrugation and the medium of the flow state. The waveform of the plate includes herringbone, straight, spherical and so on. After years of research and experiments, it has been found that the shape of the corrugated cross-section is triangular (the larger the heat transfer coefficient of the sinusoidal surface, the smaller the pressure drop, the uniform stress distribution under compression, but the processing is difficult) The herringbone plate has a higher surface transmission coefficient. The larger the included angle of the corrugations, the higher the flow velocity of the medium in the flow channel between the plates, and the larger the surface heat transfer coefficient.
b. Reduce the thermal resistance of the dirt layer
The key to reducing the thermal resistance of the fouling layer of the reversing equipment is to prevent the fouling of the plates. When the fouling thickness of the plate is 1 mm, the heat transfer coefficient is reduced by about 10%. Therefore, attention must be paid to monitoring the water quality of the hot and cold sides of the reversing equipment to prevent scaling of the plates and prevent debris in the water from adhering to the plates. In order to prevent water theft and corrosion of steel parts, some heating units add chemicals to the heating medium, so it is necessary to pay attention to the water quality and adhesives that cause debris to contaminate the reversing equipment plates. If there is sticky debris in the water, it should be treated with a special filter. When choosing a medicament, it is advisable to choose a non-sticky medicament.