From f97c0f81ab7c078bd73790102155ed52d2d8c533 Mon Sep 17 00:00:00 2001
From: Hrvoje Jasak <h.jasak@wikki.co.uk>
Date: Tue, 30 Apr 2019 15:44:09 +0100
Subject: [PATCH] Updated I/O handling of fixed gradient and mixed FV patches
 for DLB.  Vuko Vukcevic

---
 .../fixedGradient/fixedGradientFvPatchField.C | 22 +++++++++++++++----
 .../basic/mixed/mixedFvPatchField.C           | 17 ++++++++++----
 .../basic/transform/transformFvPatchField.C   |  2 +-
 3 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/src/finiteVolume/fields/fvPatchFields/basic/fixedGradient/fixedGradientFvPatchField.C b/src/finiteVolume/fields/fvPatchFields/basic/fixedGradient/fixedGradientFvPatchField.C
index fa1a73466..3e8437239 100644
--- a/src/finiteVolume/fields/fvPatchFields/basic/fixedGradient/fixedGradientFvPatchField.C
+++ b/src/finiteVolume/fields/fvPatchFields/basic/fixedGradient/fixedGradientFvPatchField.C
@@ -67,11 +67,20 @@ fixedGradientFvPatchField<Type>::fixedGradientFvPatchField
     const dictionary& dict
 )
 :
-    // HR 15.12.18: Must not call evaluate during construction. Read value
-    // instead. This is needed for PLB.
-    fvPatchField<Type>(p, iF, dict, true),
+    fvPatchField<Type>(p, iF, dict),
     gradient_("gradient", dict, p.size())
-{}
+{
+    // Call evaluate only if the value is not found. Used to avoid evaluating
+    // when we have incomplete meshes during Parallel Load Balancing. When
+    // shipping the field over to another processor, we first call write, making
+    // sure that the value is written and read it on the other side (see
+    // write member function). If this proves to be problematic, we can always
+    // initialize with patch internal field for the start-up. VV, 12/Apr/2019.
+    if (!dict.found("value"))
+    {
+        evaluate();
+    }
+}
 
 
 template<class Type>
@@ -190,6 +199,11 @@ void fixedGradientFvPatchField<Type>::write(Ostream& os) const
 {
     fvPatchField<Type>::write(os);
     gradient_.writeEntry("gradient", os);
+
+    // Write value along with the gradient in order to avoid calling evaluate
+    // on construction (from dictionary constructor) for Parallel Load Balancing
+    // runs. See dictionary constructor for details. VV, 12/Apr/2019.
+    this->writeEntry("value", os);
 }
 
 
diff --git a/src/finiteVolume/fields/fvPatchFields/basic/mixed/mixedFvPatchField.C b/src/finiteVolume/fields/fvPatchFields/basic/mixed/mixedFvPatchField.C
index e542db57b..2223cc6d4 100644
--- a/src/finiteVolume/fields/fvPatchFields/basic/mixed/mixedFvPatchField.C
+++ b/src/finiteVolume/fields/fvPatchFields/basic/mixed/mixedFvPatchField.C
@@ -54,13 +54,22 @@ mixedFvPatchField<Type>::mixedFvPatchField
     const dictionary& dict
 )
 :
-    // HR 15.12.18: Must not call evaluate during construction. Read value
-    // instead. This is needed for PLB.
-    fvPatchField<Type>(p, iF, dict, true),
+    fvPatchField<Type>(p, iF, dict),
     refValue_("refValue", dict, p.size()),
     refGrad_("refGradient", dict, p.size()),
     valueFraction_("valueFraction", dict, p.size())
-{}
+{
+    // Call evaluate only if the value is not found. Used to avoid evaluating
+    // when we have incomplete meshes during Parallel Load Balancing. When
+    // shipping the field over to another processor, we first call write, making
+    // sure that the value is written and read it on the other side (see
+    // write member function). If this proves to be problematic, we can always
+    // initialize with patch internal field for the start-up. VV, 12/Apr/2019.
+    if (!dict.found("value"))
+    {
+        evaluate();
+    }
+}
 
 
 template<class Type>
diff --git a/src/finiteVolume/fields/fvPatchFields/basic/transform/transformFvPatchField.C b/src/finiteVolume/fields/fvPatchFields/basic/transform/transformFvPatchField.C
index 27d6dd2c2..1199f4e87 100644
--- a/src/finiteVolume/fields/fvPatchFields/basic/transform/transformFvPatchField.C
+++ b/src/finiteVolume/fields/fvPatchFields/basic/transform/transformFvPatchField.C
@@ -41,7 +41,7 @@ transformFvPatchField<Type>::transformFvPatchField
     const DimensionedField<Type, volMesh>& iF
 )
 :
-   fvPatchField<Type>(p, iF)
+    fvPatchField<Type>(p, iF)
 {}