2. Forecast
Recently, automobile industry started utilizing computer
simulations like CFD(Computational Fluid Dynamics) to
develop and design car body. Previously, it prepared actual car
body model, and it evaluated car body aerodynamic character
by running wind tunnel test. To prepare actual car body model
takes time and cost. Therefore, it tended to decrease wind
tunnel test and increase computer simulation. But, to re-enact
actual car running had difficulty in CFD, and it had some
problems like computational result accuracy.
3. Outline
I use an open source simulation software which name is
OpenFOAM. Here is how to simulate. First, I get the 3D data of
a car. I can not make whole car body 3D model on my own. So
I get it from web. Next, I decide a size of virtual wind tunnel
and position of car model in it. After that, I generate some grids
for calculation, it is called “mesh”. Next, I set boundary
condition like inlet of air flow. After that, I execute a
simulation. Finally, I display a result by visualize software
called “paraView” after finished simulation. It can display
stream line, cut by X or Y or Z axis, and so on.
4. Motivation and Problem Statement
Past CFD were a lot of simulations when a car running straight
line, and low simulations when it running corner. Therefore,
including cornering, I want to do simulations more real car
running, so I tried this research. Here, I aimed to more real
simulations to actual car running by comparing the flow of the
air when the car running straight line with when it running
corner by CFD.
5. Methods
First, creating a model data. Creating 3D or 2D model by CAD
data. This model will be simulation objective. Second, mesh
generation. CFD expresses calculational space in mesh. This
number of mesh is very important for accuracy. A lot of mesh
provide good accuracy, but it needs long calculation time. So I
must find good balance. Third, running calculation. My
laboratory has super computer. In CFD, calculation time is very
long. So I need high spec computer. Finally,
visualization. Calculation result is difficult for human eyes to
understand.
8. Summary
This is low quality simulation. So I must do more high quality
simulation. Two graphics shows air flow around a car. But they
are not easy to understand. So I must fix graphics, too.
