In tube heat exchanger, the surface area of tube bundle is the heat transfer area of heat exchanger. When the heat transfer area is large and the number of tubes is large, in order to improve the flow velocity of the fluid in the tubes and increase the heat transfer film coefficient of the fluid on one side of the tubes, all the tubes are often divided into several groups on average, and the fluid only flows through one group of tubes at a time, that is, the multi-tube pass structure is adopted. The method comprises the following steps: installing a partition plate in a head, and installing the partition plate in a head at one end to form two pipe passes; Install two baffles at the inlet end and one baffle at the other end to form a four-tube channel; In this way, other multi-tube passes can be set, but too many will increase the fluid resistance, the partition will occupy the area of the distribution tube, and the heat transfer area will decrease.
In the condenser used for alcohol distillation, in order to improve the fluid velocity in the shell, a certain number of baffles perpendicular to the tube bundle are usually installed in the shell. There are two common types of baffles: circular notch (also known as bow plate) and disc ring.