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Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Author: dutta-alankar

doc/source/modules/radCooling.rst

@@ -7,10 +7,10 @@ Equations solved and method
 ---------------------------
 
 The ``RadiativeCooling`` module implements the computation of the loss of internal thermal energy
-due radiation in an optically thin medium. Physically, it solves for :math:`\dot_{e}=\mathcal{L}`,
-where we have used :math:`\mathcal{L}=-n_H^2 \Lambda (T)` (where :math:`T` is the gas temperature,
-:math:`n_H=\rho X_H/m_p` is the total hydrogen number density, and :math:`\Lambda(T)`) is the
-radiative cooling rate computed seperately from quantum mechanical calculations
+due to radiation in an optically thin medium. Physically, it solves for :math:`\dot{e}=\mathcal{L}`,
+where we have used :math:`\mathcal{L}=-n_H^2 \Lambda(T)` (where :math:`T` is the gas temperature,
+:math:`n_H=\rho X_H/m_p` is the total hydrogen number density, and :math:`\Lambda(T)` is the
+radiative cooling rate computed separately from quantum mechanical calculations
 by other plasma modeling codes, for example, Cloudy (Ferland et. al, PASP 110, 749 (1998)).
 
 This computation becomes especially relevant for multiphase gas in astrophysical environments

src/fluid/addSourceTerms.hpp

@@ -204,9 +204,11 @@ struct Fluid_AddSourceTermsFunctor {
       Uc(MX2,k,j,i) += dt*Sm / rt(i);
   #endif // COMPONENTS
 #endif
+#if HAVE_ENERGY
     if (coolingOn) {
       Uc(ENG,k,j,i) += delta_eng_cool(k,j,i); // energy per unit volume
     }
+#endif
   }
 };
 

src/fluid/cooling/cooling.cpp

@@ -164,9 +164,10 @@ void RadCooling::TownsendIntegration(real dt) {
           del_prs = -Vc(RHO,k,j,i)/(mu*m_p/kB)*(temperature-T_fin)/pow(vel_unit,2);
           delta_eng(k,j,i) = eos.GetInternalEnergy(del_prs, Vc(RHO,k,j,i));
         }
-        else {
-          del_prs = ZERO_F;
-          delta_eng(k,j,i) = ZERO_F;
+        } else {
+          T_fin = TcoolFloor;
+          del_prs = -Vc(RHO,k,j,i)/(mu*m_p/kB)*(temperature-T_fin)/pow(vel_unit,2);
+          delta_eng(k,j,i) = eos.GetInternalEnergy(del_prs, Vc(RHO,k,j,i));
         }
       }
     });

src/fluid/cooling/cooling.hpp

@@ -9,7 +9,7 @@
 #define FLUID_COOLING_COOLING_HPP_
 
 #include <string>
-
+#include <functional>
 #include "idefix.hpp"
 #include "input.hpp"
 #include "grid.hpp"