From 4796ce32bd99e1b46c3f5814982bba45ce486aba Mon Sep 17 00:00:00 2001
From: Will Bainbridge <http://cfd.direct>
Date: Thu, 6 Dec 2018 18:18:36 +0000
Subject: [PATCH] waveSuperposition: Fixed bug in gas pressure

---
 src/waves/waveSuperposition/waveSuperposition.C | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/src/waves/waveSuperposition/waveSuperposition.C b/src/waves/waveSuperposition/waveSuperposition.C
index 10934e9e23..275e204d7b 100644
--- a/src/waves/waveSuperposition/waveSuperposition.C
+++ b/src/waves/waveSuperposition/waveSuperposition.C
@@ -347,7 +347,21 @@ Foam::tmp<Foam::scalarField> Foam::waveSuperposition::pGas
     const vectorField& p
 ) const
 {
-    return - pLiquid(t, p);
+    tensor axes;
+    scalar u;
+    vectorField xyz(p.size());
+    transformation(p, axes, u, xyz);
+
+    axes = tensor(- axes.x(), - axes.y(), axes.z());
+
+    if (heightAboveWave_)
+    {
+        xyz.replace(2, height(t, p));
+    }
+
+    xyz.replace(2, - xyz.component(2));
+
+    return pressure(t, xyz);
 }