Computational Aerodynamics Questions & Answers  




Well, the file name should end with .vtk in order to be read in paraview.. I'll give you 1 point bonus boost.




The first two zeros in the Corners() command are for the $x$ and $y$ positions of the lowerleft corner. The next two values are for the $x$ and $y$ positions of the upperright corner. For the second question, yes, if is2 depends on is3, then you should initialize is3 before initializing is2. Two points bonus boost.




Hm, I don't understand what could be wrong.. You need to explain this more carefully.




An easy way around this is by moving the window so you can see the buttons at the bottom. You can move the window by pressing the key “alt”, the left mouse button, and moving the mouse around. Alternately, you can increase the resolution of your screen, but this is more involved..




Hmm, I didn't mention about the shock today and there is no reason to at this stage.. But I'll give you 0.5 point bonus for the effort.




Well the mathematical definition of $A$ is the flux jacobian, i.e. $$ A\equiv \frac{\partial F}{\partial U} $$ This was mentioned in class. 0.5 point bonus.




Yes, that is correct. But you need to demonstrate why this is through the perpendicular Mach number and wave speeds. 2 points bonus.




Very good question. I made a mistake in class: always use $M_2^n$ to estimate whether the BC is subsonic of supersonic. Please change your notes accordingly. 2 points bonus boost.




You should use 2nd degree polynomials for all properties that are used to rebuild the $U$ vector at the boundary node (i.e., $u$, $v$, $T$, $P$). 1 point bonus boost.




Hm no, there is always a stagnation point even if the flow does not come to a stop anywhere along the streamline. The stagnation point is imaginary. 1 point bonus.




You can extrapolate them directly for subsonic outflow. There is no need to obtain the Mach number needed to obtain the pressure and temperature from the stagnation properties (which are not used for subsonic outflow). However, you first need to obtain the Mach number perpendicular to the boundary $M_\perp$ to determine the wave speeds and whether the boundary condition is subsonic outflow or supersonic outflow. 1 point bonus.




Well, both the LHS and the RHS must be divided by the same amount. Thus, only the numerator on the RHS is altered. It wouldn't make sense to also divide the denominator.. 1 point bonus boost.



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