How Do You Calculate Static Pressure on Hypersonic Vehicles?

[roldy]

I'm confused about finding the static pressure on a surface of a hypersonic vehicle.

I know the inclination angle of surface 1 relative to the horizontal and I know all the aerodynamic characteristics of stage 1. With a calorically perfect gas assumption, gamma=1.4. I'm getting a little confused with static pressure and stagnation pressure. What is the appropriate equation to use?

 

[boneh3ad]

Just use the oblique shock relations. On the body you have pictured you have straight sections, so you don't need anything more complicated. If you know the incoming angle of attack and Mach number, you can generate all the information you need for static pressure using the oblique shock equations.

 

[NatSusan]

Hi there! Finding the static pressure on a surface of a hypersonic vehicle can be a bit tricky, but here's what you need to know:

Static pressure is the pressure exerted by a fluid on a surface when the fluid is not in motion. Stagnation pressure, on the other hand, is the pressure that the fluid would exert if it were brought to rest isentropically (without any losses) at a point on the surface. In other words, it's the maximum pressure that can be achieved at that point.

To find the static pressure on a surface, you can use the Bernoulli's equation, which states that the sum of the static pressure, dynamic pressure (due to the fluid's velocity), and potential energy per unit mass (due to the fluid's elevation) is constant along a streamline. In this case, since you know the aerodynamic characteristics of stage 1, you can use the Mach number and inclination angle to calculate the dynamic pressure.

However, if you're looking to find the stagnation pressure, you can use the total pressure equation, which takes into account the effects of compressibility and temperature on the fluid. This equation is more complex and involves the use of the perfect gas law and the ratio of specific heats (gamma).

In summary, to find the static pressure on a surface, use Bernoulli's equation, and to find the stagnation pressure, use the total pressure equation. I hope this helps clear up some of your confusion!