Some people think that because Concurrent CFD is so easy to use it must be simplistic. Nothing could be further from the truth. FloEFD has some very sophisticated physical models for cavitation, combustion, etc. plus by being CAD-embedded it’s also easy to use the CFD results to drive other simulation packages within the MCAD environment. Not limited to upfront design, Concurrent CFD can be used continuously during product design, leading to a more fluent design process.
That brings me on to the last of my entries about Voxdale’s work in Indy Car. A consequence of calculating the air flow over the car is that the simulation also predicts surface pressures, which when integrated over all the surfaces give the overall lift and drag on the car – key parameters that are used to decide whether one design is better than another. In Voxdale’s case they were using FloEFD.Pro inside Pro/ENGINEER Wildfire.
The aerodynamic forces on the bodywork, wings, etc. cause these structures to deform, changing their shape. To incorporate this, the guys at Voxdale used a beautifully simple and pragmatic approach by first calibrating the strength of the material used for the back wing (see below).
The surface pressures from the FloEFD.Pro simulation, shown below as a distributed surface load in Pro/MECHANICA.
The results of the Pro/MECHANICA simulation are shown below. These can be used to either refine the aerodynamic simulation by using the distorted geometry or directly to modify the body to increase its rigidity where needed, and save weight where it’s not.
I’ll have more exciting images from Voxdale later this year, so check back soon. If you’re interested in predicting reaction forces using concurrent CFD then check out our latest free on-demand we seminar Simulating and Optimizing Reaction Forces.
The webinar goes into details of how to calculate forces on a pump’s impeller.
Dr. J, Hampton Court


