Jump to content

Pyro solver - difference between inputs


Recommended Posts



What is the difference between solver inputs (pre-solve, velupdate, advection, post-solve)?


as for instance i may plug my gasfieldvop1 microsolver in any pyro solver inputs. 


the simulation looks the same in any case.


may be for this particular microsolver it does not matter , but for another microsolver it will do ?


Edited by 90okm
Link to comment
Share on other sites

correct me if i am wrong , from what i understand , 


a quick explanation to this is ,


the solver is composed of many parts which is solving the navier stokes equation for fluids , 


according the the equation the velocity is solved and updated at every point , 


so post solve and pre solve are computed before and after solving the field , which then updates the position /density/pressure etc of the point 


update velocity modifies the solved velocity field and advection uses this velocity field to advect the input points around using this filed  ,


of course there is more to solving the navier stokes equation , just to explain what these inputs are on this solver



more in depth explanation can be found here Wikipedia



Flow velocity[edit]

The solution of the Navier–Stokes equations is a flow velocity. It is a field, since it is defined at every point in a region of space and an interval of time. Once the velocity field is calculated, other quantities of interest, such as pressure or temperature, may be found. This is different from what one normally sees in classical mechanics, where solutions are typically trajectories of position of a particle or deflection of a continuum. Studying velocity instead of position makes more sense for a fluid; however for visualization purposes one can compute various trajectories.

General continuum equations[edit]

The Navier–Stokes momentum equation can be derived as a particular form of the Cauchy momentum equation. In an inertial frame of reference, the conservation form of the equations ofcontinuum[disambiguation needed] motion is:[2]

Cauchy momentum equation (conservation form)



f7f177957cf064a93e9811df8fe65ed1.png is the density, 25cdaba0e466192c4086c413c442def1.png is the flow velocity, fe3a83e41074834731743ab803cd4936.png is the del operator. 83878c91171338902e0fe0fb97a8c47a.png is the pressure 99390491be8757c2d00ba9ba45ee07d7.png is the identity matrix 733cff0c4621f85c07c6b39de9d3d811.png is the deviatoric stress tensor, which has order two, d244311c3a4861b5395d37e68ceba14a.png represents body accelerations (per unit mass) acting on the continuum, for example gravityinertial accelerationselectric field acceleration, and so on.





Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...