Tech Briefs

Thermal Fluid-Structure Interaction including Shell Elements

Shell and beam elements have been used extensively in ADINA in the analysis of problems involving fluid-structure interaction (FSI). This capability is greatly enhanced in version 8.2 by allowing also beams and shells in the analysis of thermal fluid-structure interaction (TFSI) problems. With these enhancements, it is now possible to model thin structures in TFSI problems with shell elements instead of solid elements. Some applications are the modeling of coolant pipes in power plants, components mounted on printed circuit boards, and pipes in heat exchangers.

We demonstrate the new capability using the example shown below. Air flows past a box in order to cool the box because heat is generated inside the box.

Due to symmetry, the model (shown in red) includes only half of the box and the domain of the air. The box is modeled structurally with shell elements. The heat generation inside the box is modeled with a prescribed heat flux load on the inner walls of the box. Also the temperature of the cooling air at the inlet is prescribed.

The results are shown in the above animations. The streamlines in the top animation show the complex flow pattern around the structure. The bottom animation shows the effective stress and temperature distributions in progressive sections through the structure.