Simulation of flat plate

[vs-karthik]

Hello Gaurav,

how to simulate flat plate in xcompact3d, i mean how to get flat plate geometry since in the examples given in the github flat plate is not there .what changes did you make to get flat plate ?

[gauravity30]

You have to modify the code in BC-Cylinder.f90 file. Instead of cylinder geometry, you have to adjust the code to make the flat plate.

[vs-karthik]

Hello Gaurav I have changed the geometry subroutine in BC-Cylinder.f90 file.But, even after doing it i am getting simulation results for the cylinder. I am new to this software. It's been only a week since i'm using the software. so any source available to learn.

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On Sun, 7 Jan 2024 at 19:47, Gaurav Gupta ***@***.***> wrote: You have to modify the code in BC-Cylinder.f90 file. Instead of cylinder geometry, you have to adjust the code to make the flat plate. — Reply to this email directly, view it on GitHub <#2 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BFALQFFWS6ITF7W6UWNRX5LYNKU6ZAVCNFSM6AAAAABBQK7O3SVHI2DSMVQWIX3LMV43SRDJONRXK43TNFXW4Q3PNVWWK3TUHM4DAMZXGE4DK> . You are receiving this because you authored the thread.Message ID: <airwarriorg91/xcompact3d-STL-importer/repo-discussions/2/comments/8037185 @github.com>

[gauravity30]

Can you post the code modifications and mention which file you changed ?

For learning: Read the reference papers and documentation. Rest is just practice and doing it on your own. That's how I am learning. You can surely take help from your guide/peer.

[vs-karthik]

I have only replaced the subroutine of cylinder geometry with the flat plate geometry and the remaining code I have left as it is. I have attached the file in this mail.

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On Mon, 8 Jan 2024 at 19:10, Gaurav Gupta ***@***.***> wrote: Can you post the code modifications and mention which file you changed ? — Reply to this email directly, view it on GitHub <#2 (reply in thread)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BFALQFEVT7AFO6G2M6HNNQ3YNPZOTAVCNFSM6AAAAABBQK7O3SVHI2DSMVQWIX3LMV43SRDJONRXK43TNFXW4Q3PNVWWK3TUHM4DANBZHAZTM> . You are receiving this because you authored the thread.Message ID: <airwarriorg91/xcompact3d-STL-importer/repo-discussions/2/comments/8049836 @github.com>

[gauravity30]

I am not able to find the code. Kindly check again.

You can just copy paste the changes here and put it inside the code block. Check GitHub markup syntax for more info.

Sample Code 

[vs-karthik]

I think now you can find the attached file.

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On Tue, 9 Jan 2024 at 00:41, Gaurav Gupta ***@***.***> wrote: I am not able to find the code. Kindly check again. — Reply to this email directly, view it on GitHub <#2 (reply in thread)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BFALQFGE5YLNBBPZ7P7X3ODYNRAGHAVCNFSM6AAAAABBQK7O3SVHI2DSMVQWIX3LMV43SRDJONRXK43TNFXW4Q3PNVWWK3TUHM4DANJUGM4DE> . You are receiving this because you authored the thread.Message ID: <airwarriorg91/xcompact3d-STL-importer/repo-discussions/2/comments/8054382 @github.com>

[gauravity30]

No, kindly put the code as a code block in a comment.

[vs-karthik]

PROGRAM FlatPlateGeometry
  USE decomp_2d
  IMPLICIT NONE

  INTEGER, PARAMETER :: nx = 100  ! Number of grid points in the x-direction
  INTEGER, PARAMETER :: ny = 100  ! Number of grid points in the y-direction
  INTEGER, PARAMETER :: nz = 50   ! Number of grid points in the z-direction
  REAL(mytype), PARAMETER :: dx = 0.1_mytype  ! Spatial grid spacing
  REAL(mytype), PARAMETER :: plate_height = 10.0_mytype ! Height of the flat plate
  REAL(mytype), PARAMETER :: remp = 1.0_mytype ! Value assigned within the plate region

  REAL(mytype), DIMENSION(nxi:nxf, nyi:nyf, nzi:nzf) :: epsi

  ! Call the subroutine to create the flat plate geometry
  CALL geom_flat_plate_centered(epsi, 1, nx, 1, ny, 1, nz, dx, plate_height, remp)

  ! Your simulation or further processing can be done here

END PROGRAM FlatPlateGeometry

! Subroutine to create a flat plate geometry centered within the domain
SUBROUTINE geom_flat_plate_centered(epsi, nxi, nxf, nyi, nyf, nzi, nzf, dx, plate_height, remp)
  USE decomp_2d
  IMPLICIT NONE

  REAL(mytype), DIMENSION(nxi:nxf, nyi:nyf, nzi:nzf), INTENT(OUT) :: epsi
  INTEGER, INTENT(IN) :: nxi, nxf, nyi, nyf, nzi, nzf
  REAL(mytype), INTENT(IN) :: dx, plate_height, remp

  INTEGER :: i, j, k
  REAL(mytype) :: plate_center, plate_bottom

  ! Calculate the center and bottom position of the flat plate
  plate_center = 0.5_mytype * (nyi + nyf) * dx
  plate_bottom = plate_center - 0.5_mytype * plate_height

  ! Initialize epsi
  epsi(:,:,:) = 0.0_mytype

  ! Create flat plate geometry centered in the domain
  DO k = nzi, nzf
    DO j = nyi, nyf
      DO i = nxi, nxf
        IF (REAL(j, mytype) * dx .LE. plate_bottom + plate_height .AND. &
            REAL(j, mytype) * dx .GE. plate_bottom) THEN
          epsi(i, j, k) = remp
        ENDIF
      END DO
    END DO
  END DO

END SUBROUTINE geom_flat_plate_centered

instead of cylinder geometry i have replaced it with this. and remaining code i left is as it.

[gauravity30]

No, this not how you implement the flat plate geometry. Are you using our library to convert a STL file in xcompact3d. Also, note our library currently only works with the iibm=1 i.e. simple IBM method. Also, you need to just simply modify the code in the geomcomplex_cyl subroutine.

The attached code creates a simple flat plate without the use of our library and works for all the IBM methods supported by xcompact3D. Thus, I if you wish to simulate over a simple flat plate then use the code otherwise you can use our library to import a complex geometry.

I hope it solves your issue !

  subroutine geomcomplex_cyl(epsi,nxi,nxf,ny,nyi,nyf,nzi,nzf,dx,yp,remp)

    use decomp_2d, only : mytype
    use param, only : one, two, ten
    use ibm_param
    use dbg_schemes, only: sqrt_prec

    implicit none

    integer                    :: nxi,nxf,ny,nyi,nyf,nzi,nzf
    real(mytype),dimension(nxi:nxf,nyi:nyf,nzi:nzf) :: epsi
    real(mytype),dimension(ny) :: yp
    real(mytype)               :: dx
    real(mytype)               :: remp
    integer                    :: i,j,k
    real(mytype)               :: xm,ym,r,rads2,kcon
    real(mytype)               :: zeromach, ca, sa, dxx, dyy, xr, yr
    real(mytype)               :: cexx,ceyy,dist_axi

    zeromach=one
    do while ((one + zeromach / two) .gt. one)
       zeromach = zeromach/two
    end do
    zeromach = ten*zeromach

    ! Intitialise epsi
    epsi(:,:,:)=zero

    ! Update center of moving Cylinder
    !cexx=cex+ubcx*t
    !ceyy=cey+ubcy*t
    ! Update center of moving Cylinder
    if (t.ne.0.) then
       cexx=cex+ubcx*(t-ifirst*dt)
       ceyy=cey+ubcy*(t-ifirst*dt)
    else
       cexx=cex
       ceyy=cey
    endif
    !
    ! Define adjusted smoothing constant
!    kcon = log((one-0.0001)/0.0001)/(smoopar*0.5*dx) ! 0.0001 is the y-value, smoopar: desired number of affected points 
!   
    ! A (angle of attack) = 10 deg ! Adjust according to your need.
    sa = 0.173648177
    ca = 0.984807753
    print *, 'cos(A)', ca
    print *, 'sin(A)', sa
    print *, 'remp', remp
    
    do k=nzi,nzf
       do j=nyi,nyf
          ym=yp(j)
          do i=nxi,nxf
             xm=real(i-1,mytype)*dx
             dxx = xm - cexx
  	     dyy = ym - ceyy
             xr = dxx * ca - dyy * sa
	     yr = dxx * sa + dyy * ca

             if (abs(xr) <= ra .AND. abs(yr) <= 0.013 * ra) then
                epsi(i,j,k)=remp
             endif
          enddo
       enddo
    enddo

    return
  end subroutine geomcomplex_cyl