Which type of Pressure contour should I view?
 

I'm analysing an automobile on fluent and I want to know what pressure contours imply what?

The automobile is pretty huge and should have a low-pressure region behind.
If I display static contours, There is know low-pressure region behind and if I choose dynamic pressure contours I get low-pressure regions on both the front and the rear of the automobile. If I choose absolute pressure then I get a slightly low-pressure region at the back, a bit high in the front. If I choose total then I get a completely uniform pressure and a low-pressure region only at the back of the bus.

Which pressure is the one I need to refer and what does all the other pressure used for?:confused:

In common parlance, e.g. there is a low-pressure region or high-pressure region refers to the static pressure. If you are looking for the plot that should have a high pressure region in front and low pressure region in the rear, that's the static pressure plot you should be looking at.

Static pressure is the momentum associated with the random motion of molecules. Dynamic pressure is the momentum carried by directed motion of the flow. Total pressure is the sum of both static and dynamic pressure.

Total pressure decreases when there is a momentum sink. Usually, these are the irreversible viscous losses. That's why your total pressure field is mostly uniform except on the surfaces (where you find the boundary layers) and behind the car (due to the wake).

The static pressure is like the thermodynamic pressure which you would use along with static temperature to get the local state variables (local density, viscosity, and so on). The static pressure on the surfaces of the automobile is also what it experiences as mechanical forces.

Dynamic pressure tell you how fast the flow is going. Because of that, it's not that useful for looking at the local dynamic pressure, because you could just be looking at velocity instead. So not many people make plots of dynamic pressure.

Hey, thank you for the reply.
I have attached the static pressure image and the pressure isn't very low. It's almost the same as the surrounding pressure! why is that?

It looks fine. Just play with the min and max pressure on the scale.

Thank you.:)