From e2c64bb4baa64249e1401839b8500ceb5c6289ea Mon Sep 17 00:00:00 2001
From: Matthew Goodson <matthew.goodson@corvidtec.com>
Date: Tue, 7 Mar 2023 21:33:14 -0500
Subject: [PATCH 1/2] Add function to mixture to get surface radiative heat
 flux.

Add a function that can be called from the mixture object
that will return the net surface radiative heat flux.

See #303.
---
 src/gsi/GasSurfaceInteraction.cpp          |  6 ++++++
 src/gsi/GasSurfaceInteraction.h            |  7 +++++++
 src/gsi/Surface.h                          | 12 ++++++++++++
 src/gsi/SurfaceBalanceSolverMassEnergy.cpp |  9 +++++++++
 4 files changed, 34 insertions(+)

diff --git a/src/gsi/GasSurfaceInteraction.cpp b/src/gsi/GasSurfaceInteraction.cpp
index 31095b85..c6255446 100644
--- a/src/gsi/GasSurfaceInteraction.cpp
+++ b/src/gsi/GasSurfaceInteraction.cpp
@@ -216,6 +216,12 @@ void GasSurfaceInteraction::getMassBlowingRate(double& mdot){
 
 //==============================================================================
 
+void GasSurfaceInteraction::getRadiativeHeatFlux(double& qrad){
+    qrad = mp_surf->radiativeHeatFlux();
+}
+
+//==============================================================================
+
 inline void GasSurfaceInteraction::errorWrongTypeofGSIFile(
     const std::string& gsi_root_tag)
 {
diff --git a/src/gsi/GasSurfaceInteraction.h b/src/gsi/GasSurfaceInteraction.h
index 3a7313a2..95401954 100644
--- a/src/gsi/GasSurfaceInteraction.h
+++ b/src/gsi/GasSurfaceInteraction.h
@@ -179,6 +179,13 @@ class GasSurfaceInteraction
      */
     void getMassBlowingRate(double& mdot);
 
+    /**
+     * Function which returns the total radiative flux.
+     *
+     * @param qrad on return radiative heat flux W/m^2
+     */
+    void getRadiativeHeatFlux(double& qrad);
+
 private:
     /**
      * Error function; wrong type of Gas Surface Interaction input file.
diff --git a/src/gsi/Surface.h b/src/gsi/Surface.h
index 8e2f7b54..1b69eeea 100644
--- a/src/gsi/Surface.h
+++ b/src/gsi/Surface.h
@@ -193,6 +193,18 @@ class Surface
      */
     virtual double massBlowingRate() = 0;
 
+//==============================================================================
+
+    /**
+     * Purely virtual function returning the net radiative heat flux.
+     */
+    virtual double radiativeHeatFlux()
+    {
+        throw LogicError()
+        << "radiativeHeatFlux can be called only when solving "
+        << "the surface energy balance!";
+    }
+
 //==============================================================================
 
 };
diff --git a/src/gsi/SurfaceBalanceSolverMassEnergy.cpp b/src/gsi/SurfaceBalanceSolverMassEnergy.cpp
index 01087b2a..701f7b4f 100644
--- a/src/gsi/SurfaceBalanceSolverMassEnergy.cpp
+++ b/src/gsi/SurfaceBalanceSolverMassEnergy.cpp
@@ -239,6 +239,15 @@ class SurfaceBalanceSolverMassEnergy :
         return 0.;
     }
 
+//==============================================================================
+
+    double radiativeHeatFlux()
+    {
+        if (mp_surf_rad != NULL)
+            return mp_surf_rad->surfaceNetRadiativeHeatFlux();
+        return 0.;
+    }
+
 //==============================================================================
 
     void updateFunction(Eigen::VectorXd& v_X)

From 309b62bb31a908c793b3affa8c23137d2c0b13ba Mon Sep 17 00:00:00 2001
From: Matthew Goodson <matthew.goodson@corvidtec.com>
Date: Tue, 7 Mar 2023 21:41:31 -0500
Subject: [PATCH 2/2] Add function to mixture to get surface emissivity.

Add a function to the mixture object to return the
surface emissivity.

See #303.
---
 src/gsi/GasSurfaceInteraction.cpp          |  6 ++++++
 src/gsi/GasSurfaceInteraction.h            |  7 +++++++
 src/gsi/Surface.h                          | 12 ++++++++++++
 src/gsi/SurfaceBalanceSolverMassEnergy.cpp |  9 +++++++++
 src/gsi/SurfaceRadiation.cpp               |  7 +++++++
 src/gsi/SurfaceRadiation.h                 |  6 ++++++
 6 files changed, 47 insertions(+)

diff --git a/src/gsi/GasSurfaceInteraction.cpp b/src/gsi/GasSurfaceInteraction.cpp
index c6255446..73450ad7 100644
--- a/src/gsi/GasSurfaceInteraction.cpp
+++ b/src/gsi/GasSurfaceInteraction.cpp
@@ -222,6 +222,12 @@ void GasSurfaceInteraction::getRadiativeHeatFlux(double& qrad){
 
 //==============================================================================
 
+void GasSurfaceInteraction::getSurfaceEmissivity(double& eps){
+    eps = mp_surf->surfaceEmissivity();
+}
+
+//==============================================================================
+
 inline void GasSurfaceInteraction::errorWrongTypeofGSIFile(
     const std::string& gsi_root_tag)
 {
diff --git a/src/gsi/GasSurfaceInteraction.h b/src/gsi/GasSurfaceInteraction.h
index 95401954..74e07ce5 100644
--- a/src/gsi/GasSurfaceInteraction.h
+++ b/src/gsi/GasSurfaceInteraction.h
@@ -186,6 +186,13 @@ class GasSurfaceInteraction
      */
     void getRadiativeHeatFlux(double& qrad);
 
+    /**
+     * Function which returns the surface emissivity.
+     *
+     * @param eps on return surface emissivity
+     */
+    void getSurfaceEmissivity(double& eps);
+
 private:
     /**
      * Error function; wrong type of Gas Surface Interaction input file.
diff --git a/src/gsi/Surface.h b/src/gsi/Surface.h
index 1b69eeea..b2ca4e8a 100644
--- a/src/gsi/Surface.h
+++ b/src/gsi/Surface.h
@@ -205,6 +205,18 @@ class Surface
         << "the surface energy balance!";
     }
 
+//==============================================================================
+
+    /**
+     * Purely virtual function returning the surface emissivity.
+     */
+    virtual double surfaceEmissivity()
+    {
+        throw LogicError()
+        << "emissivity can be called only when solving "
+        << "the surface energy balance!";
+    }
+
 //==============================================================================
 
 };
diff --git a/src/gsi/SurfaceBalanceSolverMassEnergy.cpp b/src/gsi/SurfaceBalanceSolverMassEnergy.cpp
index 701f7b4f..31a76e9b 100644
--- a/src/gsi/SurfaceBalanceSolverMassEnergy.cpp
+++ b/src/gsi/SurfaceBalanceSolverMassEnergy.cpp
@@ -248,6 +248,15 @@ class SurfaceBalanceSolverMassEnergy :
         return 0.;
     }
 
+//==============================================================================
+
+    double surfaceEmissivity()
+    {
+        if (mp_surf_rad != NULL)
+            return mp_surf_rad->surfaceEmissivity();
+        return 0.;
+    }
+
 //==============================================================================
 
     void updateFunction(Eigen::VectorXd& v_X)
diff --git a/src/gsi/SurfaceRadiation.cpp b/src/gsi/SurfaceRadiation.cpp
index 1c7f31e2..fb324732 100644
--- a/src/gsi/SurfaceRadiation.cpp
+++ b/src/gsi/SurfaceRadiation.cpp
@@ -72,5 +72,12 @@ double SurfaceRadiation::surfaceNetRadiativeHeatFlux()
     return m_eps * (Mutation::SB * std::pow(T_surf, 4.0) - m_gas_rad_heat_flux);
 }
 
+//==============================================================================
+
+double SurfaceRadiation::surfaceEmissivity()
+{
+    return m_eps;
+}
+
     } // namespace GasSurfaceInteraction
 } // namespace Mutation
diff --git a/src/gsi/SurfaceRadiation.h b/src/gsi/SurfaceRadiation.h
index 98d21197..e99f8e16 100644
--- a/src/gsi/SurfaceRadiation.h
+++ b/src/gsi/SurfaceRadiation.h
@@ -73,6 +73,12 @@ class SurfaceRadiation
      */
     double surfaceNetRadiativeHeatFlux();
 
+//==============================================================================
+    /**
+     *  Function which returns the surface emissivity.
+     */
+    double surfaceEmissivity();
+
 //==============================================================================
     /**
      *  Function which takes the incoming radiative heat from the gas .