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Dynamic pressure on a surface?

  1. Jan 22, 2008 #1
    Hello all,

    How would I calculate the pressure exerted on a surface by an engine in a vacuum, for example, if a lander was landing on Mars, I'm trying to calculate the pressure exerted on the surface by the exhaust. Should I simply be looking at P=F/A or should I be looking at dynamic pressure?

    Thanks in advance
  2. jcsd
  3. Jan 22, 2008 #2


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    Staff: Mentor

    For pressure exerted on a surface by a moving fluid perpendicular to it, the static pressure is equal to the velocity pressure, and p=f/a applies.
    Last edited: Jan 22, 2008
  4. Jan 22, 2008 #3
    Hi Russ,

    Thanks for your reply, so where does the dynamic pressure come into it? If you were to calculate the Dynamic Pressure what would you be calculating?
  5. Jan 22, 2008 #4
    total pressure = P_hyd + P_stat + 1/2 * Rho * V^2
    (V is bulk velocity)
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