From c58fa1c07575c4e696affaa63a1365ef2172f714 Mon Sep 17 00:00:00 2001
From: Will Bainbridge <http://cfd.direct>
Date: Wed, 25 May 2022 12:44:14 +0100
Subject: [PATCH] fvMeshStitchers::moving: Prevent communication missmatch

The sub mesh on which mesh fluxes are corrected potentially only exists
on a small subset of the processors. This was causing issues when
processor boundaries were evaluated as this triggered the construction
of weights and delta coefficients on only some of the processors,
causing a communications missmatch. This has been resolved by a
pre-emptive call to construct the surface interpolation coefficients.
---
 src/fvMeshStitchers/moving/fvMeshStitchersMoving.C | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/fvMeshStitchers/moving/fvMeshStitchersMoving.C b/src/fvMeshStitchers/moving/fvMeshStitchersMoving.C
index ae7610066b..245cb9399d 100644
--- a/src/fvMeshStitchers/moving/fvMeshStitchersMoving.C
+++ b/src/fvMeshStitchers/moving/fvMeshStitchersMoving.C
@@ -297,6 +297,7 @@ void Foam::fvMeshStitchers::moving::internalFaceCorrectMeshPhi
     fvMeshSubset subsetter(mesh());
     subsetter.setLargeCellSubset(ownerCoupledCellSet());
     const fvMesh& subMesh = subsetter.subMesh();
+    subMesh.deltaCoeffs();
 
     // Determine the disconnected regions of the sub mesh
     const regionSplit subMeshRegions(subMesh);