Shell and tube heat exchanger is composed of shell, heat transfer tube bundle, tube plate, baffle and tube box and other components. The shell is mostly cylindrical, with a tube bundle inside, and both ends of the tube bundle are fixed on the tube plate. Two kinds of hot and cold fluids for heat exchange, one flows in the tube, called the tube fluid; The other flows outside the tube and is called a shell side fluid.
In order to improve the heat transfer coefficient of the fluid outside the tube, several baffles are usually installed in the shell. The baffle can increase the velocity of the fluid on the shell side, force the fluid to pass through the tube bundle several times according to the prescribed course, and enhance the turbulence degree of the fluid. The heat exchange tube can be arranged in an equilateral triangle or square on the tube plate. The equilateral triangle arrangement is compact, the fluid turbulence outside the tube is high, and the heat transfer coefficient is large. The square arrangement is convenient for cleaning outside the tube and is suitable for the fluid that is easy to form scale.
The main control parameters of shell and tube heat exchanger are heating area, hot water flow rate, heat transfer quantity, heat medium parameters and so on.
