Home / Examples / Coupled Analysis / Fluid-Thermal Analysis [Bernoulli/Watt] / Example 13: Heat Exchanger

Example 13: Heat Exchanger

General

A shell and tube heat exchanger is analyzed.
The temperature distribution and the heat flux vectors are solved.
The results can be viewed by simultaneously displaying temperature contours and streamlines.
Unless specified in the list below, the default conditions will be applied.

Results will vary depending on Femtet version and the PC environment.

Analysis Space

Item	Settings
Analysis Space	3D
Model Unit	m

Analysis Condition

Item	Settings
Solver	Fluid Analysis [Bernoulli] Thermal Analysis [Watt]
Analysis Type	Fluid Analysis: Steady-state Analysis Thermal Analysis: Steady-state Analysis
Meshing Setup	General Mesh size: 0.03 [mm] Mesh Size of the Inside of Inlet/Outlet of the Shell: 0.01 [mm]

Model

The coolant flows in the shell and the heat medium flows in the tube. The shell and the tube are made of solid body having thickness.

The coolant and the heat medium are air. The heat exchange takes place only through the tube of solid.

Body Attributes and Materials

Body Number/Type	Body Attribute Name	Material Name
6/Solid	Tube	104_Stainless_steel *
38/Solid	Heat	000_Air *
45/Solid	Shell	104_Stainless_steel *
46/Solid	Cool	000_Air *

* Available from the material DB

Boundary Condition

Boundary Condition Name/Topology	Tab	Boundary Condition Type	Setting
CoolIn/Face	Fluid-Thermal	Inlet	Specify [Flow Velocity] 1 [m/s] Fluid Temperature Direct Entry 20 [deg]
CoolOut/Face	Fluid-Thermal	Temperature	Outlet Natural Outflow
HeatIn/Face	Fluid-Thermal	Temperature	Specify [Flow Velocity] 1 [m/s] Fluid Temperature Direct Entry 200 [deg]
HeatOut/Face	Fluid-Thermal	Temperature	Outlet Natural Outflow

Results

Fig. 1 shows the temperatures of the inside and the outside of the tube. The area where the coolant flows in and blows over the tube shows the lowest temperature.

The inlet temperature is 200 deg and the outlet temperature is about 170 deg, indicating that the heat exchange has taken place.

Example 71 of Stress Analysis is conducted using this temperature distribution.

Fig. 1: Temperature Contour Diagram of Tube

In Fig. 2, the coolant inside the shell is hidden. The temperature contours of the tube and the streamlines in the shell are simultaneously displayed.

Fig. 2: Temperature and Streamlines in Simultaneous Display