So, what is the heat transfer process? In the BOX TYPE BOCK CONDENSING UNIT refrigeration system, the high-temperature and high-pressure refrigerant vapor entering the condenser is condensed into liquid by the air or cooling water in the surrounding environment; the low-temperature refrigerant liquid entering the evaporator is cooled from the surrounding air or cooling water. It absorbs heat and vaporizes in the agent, so that the temperature of a certain area is lowered to achieve the purpose of refrigeration. The process of transferring heat between the refrigerant and the surrounding fluid through the tube wall is called a heat transfer process.
According to the form of the solid wall, there are three main heat transfer processes in the commonly used BOX TYPE BOCK CONDENSING UNIT, namely the heat transfer process through the flat wall, the heat transfer process through the round tube and the heat transfer process through the wall.
1. Flat-wall heat transfer: When the heat transfer wall is a flat plate, or can be approximated as a flat wall, heat is transferred from the high-temperature liquid on one side to the low-temperature fluid on the other side through the wall, forming a heat transfer through the flat wall. heat transfer.
2. Round tube heat transfer: In the condenser and evaporator of BOX TYPE BOCK CONDENSING UNIT, a large number of copper and steel heat transfer tubes are used, so the heat transfer through the round tube is very common.
3. Heat transfer of the wall: It can be seen from the heat transfer equation of BOX TYPE BOCK CONDENSING UNIT that the heat transfer per unit time not only increases with the increase of the heat transfer coefficient, but also increases with the increase of the heat transfer surface. big. When the heat transfer coefficient increases to a certain extent and it is difficult to increase, the heat transfer can be increased by increasing the heat transfer denomination, usually by processing fins or fins on the heat exchange wall.