From 99b36f646a2b6ae49372cf3bcb381cde17a91b31 Mon Sep 17 00:00:00 2001
From: Will Bainbridge <http://cfd.direct>
Date: Tue, 18 Apr 2023 13:43:06 +0100
Subject: [PATCH] fv::zeroDimensionalMassSource: Prevent field copy

---
 .../zeroDimensionalMassSource/zeroDimensionalMassSource.C       | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/fvModels/zeroDimensional/zeroDimensionalMassSource/zeroDimensionalMassSource.C b/src/fvModels/zeroDimensional/zeroDimensionalMassSource/zeroDimensionalMassSource.C
index 55b33aecf3..a50aacd394 100644
--- a/src/fvModels/zeroDimensional/zeroDimensionalMassSource/zeroDimensionalMassSource.C
+++ b/src/fvModels/zeroDimensional/zeroDimensionalMassSource/zeroDimensionalMassSource.C
@@ -65,7 +65,7 @@ Foam::fv::zeroDimensionalMassSource::calcM0D() const
 
         if (thermo.phaseName() != word::null)
         {
-            const volScalarField alpha =
+            const volScalarField& alpha =
                 mesh().lookupObject<volScalarField>
                 (
                     IOobject::groupName("alpha", phaseName_)