Hello,
I'm studying the reflection of a shock wave over a ramp. I first
studied the problem using the body_roe solver. To evaluate the
precision of the solution I tried to use other solvers, like the
godunov_km for example, but I obtained only unrealistic solutions.
Is the body_roe solver the only one able to treat the problem? Or are
there also some versions of the other solvers for the ramp problem?\
Thanks
Andrea
> Hello, > I'm studying the reflection of a shock wave over a ramp. I first > studied the problem using the body_roe solver. To evaluate the > precision of the solution I tried to use other solvers, like the > godunov_km for example, but I obtained only unrealistic solutions. > Is the body_roe solver the only one able to treat the problem? Or are > there also some versions of the other solvers for the ramp problem?\
Without seeing your script it's hard to determine where the problem is. But if you send me a mailit, I'll take a look at it.
If you're using the ramp.mailit from the VKI notes then please be aware that it is showing its age i.e. it's more klunky than it needs to be. A better place to start would be:
amrcp latex/method.3
which itself can be polished to give the attached. Note to run these examples you will need to fix a bug that I recently posted to the newsgroup.
Once you can run the attached, you can convert the CylinderProblem into a WedgeProblem by changing the level-set passed to the routine:
AXS::InternalBoundary
It defines a distance function from a cell to the body of interest.
> thank you very much for your advice. I'll start to look at the script right > away. > However, there's the script I was working with.
> Andrea
Andrea,
The mailit you sent me is incomplete. At least the top-level scripts are missing the procedure BasicRampGrid2. Anyhow it looks like you've modified the ramp.mailit from the VKI notes, and as I noted earlier that particular script is a bit grungy. The smokefoil example I sent you is much more in line with how AMRITA would be programmed today. It does, however, require you to view the source with a folding editor and from your mailit I'm guessing that you're using emacs and so you won't see the source in the intended fashion.
thank you for your help. Using a level-set method the script seems to
be more accurate.
However, I'm facing another problem. I'd like to print the values of
the thermodynamic parameters along the ramp, but it seems that the
"along" command works only with a constant value of y so every time I
try to write y as a function of x I have an error. Is there another
command that work with a variable y? Or, is it possible to use the
"along" command with other frames of reference?(ie: a rotated and
translated one with the X' axis parallel to the ramp)
Thanks,
Andrea
On Jun 11, 12:35 pm, James Quirk <j...@galcit.caltech.edu> wrote:
> On Wed, 11 Jun 2008, Andrea Papi wrote:
> > James,
> > thank you very much for your advice. I'll start to look at the script right
> > away.
> > However, there's the script I was working with.
> > Andrea
> Andrea,
> The mailit you sent me is incomplete. At least the top-level scripts
> are missing the procedure BasicRampGrid2. Anyhow it looks like
> you've modified the ramp.mailit from the VKI notes, and as I noted
> earlier that particular script is a bit grungy. The smokefoil
> example I sent you is much more in line with how AMRITA would
> be programmed today. It does, however, require you to view
> the source with a folding editor and from your mailit
> I'm guessing that you're using emacs and so you won't
> see the source in the intended fashion.
> thank you for your help. Using a level-set method the script seems to > be more accurate. > However, I'm facing another problem. I'd like to print the values of > the thermodynamic parameters along the ramp, but it seems that the > "along" command works only with a constant value of y so every time I > try to write y as a function of x I have an error. Is there another > command that work with a variable y? Or, is it possible to use the > "along" command with other frames of reference?(ie: a rotated and > translated one with the X' axis parallel to the ramp)
As it stands, the along command is limited to lines of x or y = constant. I notionally have the machinery to be able to cope with arbitrary curves, but I havn't found the time to put it all together. There is, however, a probe command that can be used to interrogate the flow solution at arbitrary points. Therefore there is nothing to stop you doing something along the lines of:
do t=0,1,$dt set x #= f($t) set y #= g($t) probe Q[] at $x,$y -> Q end do