The material and shape of the metal tube shell determine its heat dissipation capacity

The smaller the surface area, the greater the power and the greater the surface load of the electric heating tube. Increasing the surface load is the most direct way to shorten the heating time while maintaining the same volume. However, the surface load cannot be increased indefinitely. If the surface load is too large, the temperature of the electric heating tube will be very high due to the heat dissipation capacity. The heat accumulated inside the tube may easily cause the tube to burst or the heating wire to burn out. The aging of the tube shortens the service life. Therefore, the excessively high working temperature is not suitable for Et appliances from a safety perspective or a practical perspective. Improving the heat dissipation rate has a more direct meaning to the performance improvement.
In the liquid environment, according to the distance distribution from the tube of the electric heating tube, the heated liquid can be divided into a laminar layer and a turbulent layer. In the laminar layer, heat conduction mainly depends on heat conduction, which is in accordance with Fourier's law, and the temperature distribution is almost linear. Because the thermal conductivity of the fluid is low, the thermal conductivity of the layer is large, so the temperature difference in the layer is large, and the slope of the temperature distribution curve is large. The fin-type electric heating tube can increase the heat dissipation area, at the same time increase the fluidity of the fluid and form a strong turbulent flow, thereby improving the heat dissipation coefficient and allowing the temperature of the heating tube to be quickly transmitted. The fin-type electric heating tube is a metal fin that is wound on the surface of the common element. The fin is wound on the outer surface of the heating tube to play the role of heat dissipation. Compared with the ordinary element, the heat dissipation area is expanded by 2-3 times, which is allowed by the fin element The surface power load is 3 to 4 times that of ordinary components. As the length of the element is shortened, its own heat loss is reduced. Under the same power conditions, it can achieve rapid temperature rise, uniform heat generation, good heat dissipation performance, and high thermal efficiency, which also extends the service life.