How to classify the heat exchanger according to the principle of action or the way of heat transfer? Heat exchange equipment classification 1. Heat exchanger classification (1) according to the action principle or heat transfer mode: direct contact heat exchanger heat storage heat exchanger inter wall heat exchanger inter wall heat exchanger 1. Direct contact heat exchanger (mixed heat exchanger) (1) principle: cold and hot fluid contact directly, mixing and transferring heat（ 2) Features: high heat transfer efficiency, large heat transfer area per unit volume, simple equipment structure and low price, where two kinds of fluids are allowed to mix. But it is only suitable for the second section of the process heat exchange equipment classification (3) application: the medium of this kind of heat exchanger is usually one kind of gas and the other kind of liquid, which is mainly the heat transfer equipment with tower equipment as the main body. It is suitable for the situation where hot and cold fluids are immiscible and allowed to mix with each other. Such as cooling tower, washing tower, jet condenser, etc. For example, in cooling towers used in chemical plants and power plants, hot water is sprayed from top to bottom, while cold air is inhaled from bottom to top. On the surface of water film or droplets and water drops of fillers, hot water and cold air contact each other for heat exchange. Hot water is cooled, and cold air is heated. Then, the two fluids are separated in time depending on the density difference between them. Section 2 heat exchange equipment classification 2. Regenerative heat exchanger (also known as regenerative heat exchanger or heat accumulator) (1) principle: it is with the help of solid with large heat capacity.