 Language

新闻中心

NEWS CENTER

How to transfer heat in plate and shell heat exchanger

Release time:

2025-04-15

The heat transfer process of shell-and-tube heat exchanger is mainly realized through heat conduction and convective heat transfer, and its core principle is that cold and hot fluids flow in the isolated tube and shell pass and transfer heat through the tube wall.

1.Structural composition

Tube Side: Fluid flows through a metal tube (heat transfer tube) inside the heat exchanger.

Shell Side: Fluid flows in the space between the shell of the heat exchanger and the tube bundle.

Baffles: Installed in the shell, baffles are used to increase fluid turbulence and improve heat transfer efficiency.

Tube Sheet: fixed tube bundle, separate tube and shell.

2.Heat transfer process steps

Heat release (hot fluid side)

High-temperature fluids (such as steam, hot water) enter the shell or pipe, and release heat during the flow process.

Heat is transferred to the other side by heat conduction through the tube wall (metal material, such as copper, stainless steel).

Heat absorption (cold fluid side)

The cryogenic fluid flows on the other side (tube or shell), absorbing the heat transferred by the tube wall and increasing the temperature.

Convective heat transfer enhancement

The baffle forces the shell flow to cross the tube bundle, increasing turbulence, reducing the thickness of the boundary layer, and improving the heat transfer efficiency.

Tubular fluids are usually designed to flow at high speeds to enhance convective heat transfer.

3.The effect of the flow mode

Counterflow: Cold and hot fluid reverse flow, uniform temperature difference distribution, the highest heat transfer efficiency.

Parallel Flow: cold and hot fluids flow in the same direction, the outlet temperature difference is small, and the efficiency is low.

Crossflow: The direction of the fluid is vertical, commonly seen in gas-liquid heat transfer.

4.Key influencing factors

Material thermal conductivity: The higher the thermal conductivity of the pipe (such as copper, titanium), the faster the heat transfer.

Temperature difference: The greater the temperature difference between cold and hot fluids, the stronger the driving force of heat transfer.

Velocity and turbulence: High velocity and turbulence can destroy the thermal boundary layer and increase the heat transfer rate.

Fouling (Fouling) : Fouling on the pipe wall will greatly reduce the heat transfer efficiency, and it needs to be cleaned regularly.