diff --git a/src/gpu/VirtualFluids_GPU/Calculation/UpdateGrid27.cpp b/src/gpu/VirtualFluids_GPU/Calculation/UpdateGrid27.cpp
index dbb568df74a06d813a7bc3c6d05a3aed0cf62198..a794757a44298d1f8572e0f8a214afbc48f031a8 100644
--- a/src/gpu/VirtualFluids_GPU/Calculation/UpdateGrid27.cpp
+++ b/src/gpu/VirtualFluids_GPU/Calculation/UpdateGrid27.cpp
@@ -1434,9 +1434,7 @@ void coarseToFine(Parameter* para, int level)
 }
 
 UpdateGrid27::UpdateGrid27() = default;
-UpdateGrid27::~UpdateGrid27() = default;
-UpdateGrid27::UpdateGrid27(const UpdateGrid27 &updateGrid) {}
-UpdateGrid27::UpdateGrid27(UpdateGrid27 &&updateGrid27) {}
+UpdateGrid27::~UpdateGrid27(){}
 
 UpdateGrid27::UpdateGrid27(Parameter *para) { 
     chooseFunctionForCollisionAndExchange(para); }
diff --git a/src/gpu/VirtualFluids_GPU/Calculation/UpdateGrid27.h b/src/gpu/VirtualFluids_GPU/Calculation/UpdateGrid27.h
index aa39b81592ffa824a1b56baa48607b4d88d2b553..9bc083731622e85605fba80ef7a3a22e5cb003f6 100644
--- a/src/gpu/VirtualFluids_GPU/Calculation/UpdateGrid27.h
+++ b/src/gpu/VirtualFluids_GPU/Calculation/UpdateGrid27.h
@@ -15,9 +15,6 @@ class UpdateGrid27
 public:
     UpdateGrid27(Parameter *para);
     ~UpdateGrid27();
-    UpdateGrid27(const UpdateGrid27 &updateGrid);
-    UpdateGrid27(UpdateGrid27 &&updateGrid27);
-
     void updateGrid27(Parameter *para, vf::gpu::Communicator *comm, CudaMemoryManager *cudaManager,
                       std::vector<std::shared_ptr<PorousMedia>> &pm, int level, unsigned int t,
                       std::vector<SPtr<Kernel>> &kernels);
@@ -26,7 +23,7 @@ private:
     UpdateGrid27();
     std::function<void(Parameter *para, std::vector<std::shared_ptr<PorousMedia>> &pm, int level, unsigned int t,
                        std::vector<SPtr<Kernel>> &kernels, vf::gpu::Communicator *comm, CudaMemoryManager *cudaManager)>
-        collisionAndExchange;
+        collisionAndExchange = NULL;
     void chooseFunctionForCollisionAndExchange(Parameter *para);
 };
 
diff --git a/src/gpu/VirtualFluids_GPU/LBM/Simulation.h b/src/gpu/VirtualFluids_GPU/LBM/Simulation.h
index 75c979107f71798ba62f1ce29b4085effca03e18..f11212edaee93a7051887c43e3135b256b2f8a48 100644
--- a/src/gpu/VirtualFluids_GPU/LBM/Simulation.h
+++ b/src/gpu/VirtualFluids_GPU/LBM/Simulation.h
@@ -112,6 +112,6 @@ protected:
 	SPtr<EnstrophyAnalyzer> enstrophyAnalyzer;
 	////////////////////////////////////////////////////////////////////////////
 
-	UPtr<UpdateGrid27> updateGrid27;
+	SPtr<UpdateGrid27> updateGrid27;
  };
 #endif