DANFOSS

Soon Danfoss will introduce the market to a brand-new frequency converter, a device used to control the speed of an electric motor. Developing a completely new frequency converter is not something Danfoss embarks on often. In the design phase, simulations had to be performed on 3D models where the results were to form the basis for the development of the inverters. Danfoss needed the resources to perform the simulations and contacted DIS.

CFD simulations provide clarity
Electronics cannot withstand high temperatures therefore it must be ensured that installed electronics do not overheat. To save time and money, DIS made a Computational Fluid Dynamics (CFD) simulation of the inverter in the design phase, where it was simulated how fluids such as water and air behave in a chosen geometry.
To solve the task and to make the devices as compact as possible the geometry was simplified in a simulation model, a 3D model of the entire device including fan, heat sink and electronics were simulated and various effects were placed in different places.

Because of the CFD simulations, it was possible to see the air flow through the frequency converter and how it cooled the electronics. In addition, it was possible to pinpoint problem areas, where the temperature rose significantly due to very little or no air exchange. Based on the results from the simulations compared to results from tests carried out on prototype inverters, DIS also came up with solution proposals for the design. The new initiatives subsequently proved to give a 37 percent better cooling as a result of the simulations.

- A simulation model allows us to be more flexible in our work and test our ideas so that we can avoid having to build too many prototypes. This saves us a lot of time. When you have a good simulation model, you can relatively quickly make changes in the virtual world and test whether the change solves the problem or creates new challenges. The simulation results and solution proposals we have received from DIS have given us very important knowledge and we are now in the process of testing the presented solution proposals, says Claus E. Jørgensen, Lead Mechanical Engineer at Danfoss.