February 7th, 2018
The design of heat exchangers—independent of the exact type—involves many challenges and is, therefore, a very interesting discipline from an engineer’s perspective.
It combines multiple physical phenomena such as fluid flow, heat transport, thermostructural stress, vibration, and corrosion that all need to be considered in the design phase in order to achieve the desired performance.
Since the underlying physics is so diverse, the need for different simulation capabilities is high in this application area. The approach of the SimScale platform, unifying different simulation capabilities within one single end-to-end CAE platform, is therefore well suited to address this particular application.
Let’s consider a thermal fluid flow analysis to study the behavior of one of the fluids within a simplified pipe heat exchanger.
We start by uploading a CAD model (STEP format) of the fluid volume that is heated from the smaller pipe in the middle. The image below shows the SimScale pre-processing viewer displaying the CAD model.
The next step is to create a computational grid for it. We used a hex-dominant mesh operation with boundary layer refinement to create the mesh. A cut view is shown in the figure below.
The last step before the simulation can be run is to set up the actual analysis. We used a solver that neglects the density-pressure coupling but accounts for the density-temperature coupling in order to resolve the convection effects.
The inner pipe is assumed to have a constant temperature while the outer walls are assumed to be adiabatic. The simulation was carried out on a 4-core machine and took approximately two hours.
The results are subsequently visualized in the integrated post-processing environment which is shown in the figure below.
It is evident that this simplified pipe heat exchanger does not perform very well. The bulk of the fluid passes the volume too far away from the heated pipes in the middle.
The insights into the behavior of the system would now allow us to make informed design decisions and optimize it early in the product development process.
Furthermore, we could run other analyses, such as a thermal-stress analysis, to determine the dimensions of the design.
Historically, running these types of analyses needed significant investments in hardware and software before one could profit from such insights. SimScale takes down these barriers and delivers access to simulation technology right through your web browser.
If you want to have a closer look at this model, take a look at this completed heat exchanger simulation.
Also, you can learn more about thermal analysis with SimScale on our website.
Discover all the simulation features provided by SimScale. Download the document below.
Subscribe to the SimScale Blog
Your hub for everything you need to know about
simulation and the world of CAE