diff --git a/tutorials/cfdemSolverPiso/ErgunTestMPI/CFD/constant/couplingProperties b/tutorials/cfdemSolverPiso/ErgunTestMPI/CFD/constant/couplingProperties
index a2dabecd..07b9c60f 100644
--- a/tutorials/cfdemSolverPiso/ErgunTestMPI/CFD/constant/couplingProperties
+++ b/tutorials/cfdemSolverPiso/ErgunTestMPI/CFD/constant/couplingProperties
@@ -61,7 +61,6 @@ forceModels
     gradPForce
     viscForce
     KochHillDrag
-    //RongDrag
     //Archimedes
     //volWeightedAverage
     //totalMomentumExchange
@@ -178,17 +177,6 @@ BeetstraDragProps
 //    verbose true;
 }
 
-RongDragProps
-{
-    verbose true;
-    velFieldName "U";
-    voidfractionFieldName "voidfraction";
-    interpolation true;
-    implForceDEM true;
-    implForceDEMaccumulated true;
-    granVelFieldName "Us";
-}
-
 virtualMassForceProps
 {
     velFieldName "U";
diff --git a/tutorials/cfdemSolverPiso/ErgunTestMPI/DEM/in.liggghts_run b/tutorials/cfdemSolverPiso/ErgunTestMPI/DEM/in.liggghts_run
index 1d1306d0..e9ab59af 100644
--- a/tutorials/cfdemSolverPiso/ErgunTestMPI/DEM/in.liggghts_run
+++ b/tutorials/cfdemSolverPiso/ErgunTestMPI/DEM/in.liggghts_run
@@ -44,7 +44,6 @@ set         group all density 2000
 # cfd coupling
 fix         cfd all couple/cfd couple_every 100 mpi
 fix         cfd2 all couple/cfd/force/implicit
-#fix         cfd2 all couple/cfd/force/accumulator RongDrag 10 1.5e-3
 #fix         cfd2 all couple/cfd/force/implicit/accumulated #CrankNicolson 0.5
 
 # apply nve integration to all particles that are inserted as single particles
diff --git a/tutorials/cfdemSolverRhoPimple/ErgunTestMPI/CFD/constant/couplingProperties b/tutorials/cfdemSolverRhoPimple/ErgunTestMPI/CFD/constant/couplingProperties
index fe393283..20ce03dd 100644
--- a/tutorials/cfdemSolverRhoPimple/ErgunTestMPI/CFD/constant/couplingProperties
+++ b/tutorials/cfdemSolverRhoPimple/ErgunTestMPI/CFD/constant/couplingProperties
@@ -61,7 +61,6 @@ forceModels
     gradPForce
     viscForce
     //KochHillDrag
-    //RongDrag
     //Archimedes
     //volWeightedAverage
     //totalMomentumExchange
@@ -200,17 +199,6 @@ BeetstraDragProps
 //    verbose true;
 }
 
-RongDragProps
-{
-    verbose true;
-    velFieldName "U";
-    voidfractionFieldName "voidfraction";
-    interpolation true;
-    implForceDEM true;
-    implForceDEMaccumulated true;
-    granVelFieldName "Us";
-}
-
 virtualMassForceProps
 {
     velFieldName "U";