From d727abc5616a264361b34b49b4e089897ffe2c8c Mon Sep 17 00:00:00 2001
From: Mike Lau <mike.lau@monash.edu>
Date: Tue, 3 May 2022 16:42:42 -0400
Subject: [PATCH] add moddump that sets solid body rotation

---
 src/utils/moddump_rotate.f90 | 46 ++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100644 src/utils/moddump_rotate.f90

diff --git a/src/utils/moddump_rotate.f90 b/src/utils/moddump_rotate.f90
new file mode 100644
index 000000000..ef21d875c
--- /dev/null
+++ b/src/utils/moddump_rotate.f90
@@ -0,0 +1,46 @@
+!--------------------------------------------------------------------------!
+! The Phantom Smoothed Particle Hydrodynamics code, by Daniel Price et al. !
+! Copyright (c) 2007-2022 The Authors (see AUTHORS)                        !
+! See LICENCE file for usage and distribution conditions                   !
+! http://phantomsph.bitbucket.io/                                          !
+!--------------------------------------------------------------------------!
+module moddump
+!
+! set solid body rotation for all gas particles about the z-axis given angular frequency
+!
+! :References: None
+!
+! :Owner: Mike Lau
+!
+! :Runtime parameters: None
+!
+! :Dependencies: None
+!
+ implicit none
+
+contains
+
+subroutine modify_dump(npart,npartoftype,massoftype,xyzh,vxyzu)
+ integer, intent(inout) :: npart
+ integer, intent(inout) :: npartoftype(:)
+ real,    intent(inout) :: massoftype(:)
+ real,    intent(inout) :: xyzh(:,:),vxyzu(:,:)
+ real                   :: omega,vphi,R
+ integer                :: i
+
+ ! Assume rotation axis is the z-axis
+ omega = 4.12e-2  ! Omega in code units
+
+ do i = 1,npart
+    R = sqrt(dot_product(xyzh(1:3,i),xyzh(1:3,i)))
+    vphi = omega*R
+    vxyzu(1,i) = -omega*xyzh(2,i)
+    vxyzu(2,i) = omega*xyzh(1,i)
+    vxyzu(3,i) = 0.
+ enddo
+
+ return
+end subroutine modify_dump
+
+end module moddump
+