diff --git a/src/gpu/VirtualFluids_GPU/Communication/ExchangeData27.cpp b/src/gpu/VirtualFluids_GPU/Communication/ExchangeData27.cpp
index 5c4ee37b4b59fd37c9f1ff02a378c575806b8d31..0bf106248d8e2d0894148c318d0c5fc6652c3869 100644
--- a/src/gpu/VirtualFluids_GPU/Communication/ExchangeData27.cpp
+++ b/src/gpu/VirtualFluids_GPU/Communication/ExchangeData27.cpp
@@ -43,20 +43,6 @@ void exchangeCollDataXGPU27(Parameter *para, vf::gpu::Communicator *comm, CudaMe
                             para->getParH(level)->recvProcessNeighborX[i].rankNeighbor);
     }
     /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-    ////start non blocking MPI send
-    //for (unsigned int i = 0; i < (unsigned int)(para->getNumberOfProcessNeighborsX(level, "send")); i++)
-    //{
-    //    comm->nbSendDataGPU(para->getParH(level)->sendProcessNeighborX[i].f[0],
-    //                        para->getParH(level)->sendProcessNeighborX[i].numberOfFs,
-    //                        para->getParH(level)->sendProcessNeighborX[i].rankNeighbor);
-    //}
-    /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-    ////Waitall
-    //if (0 < (unsigned int)(para->getNumberOfProcessNeighborsX(level, "send")))
-    //{
-    //    comm->waitallGPU();
-    //}
-    /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
     // wait for memcopy device to host to finish before sending data
     if (para->getUseStreams())
         cudaStreamSynchronize(stream); 
@@ -152,20 +138,6 @@ void exchangeCollDataYGPU27(Parameter *para, vf::gpu::Communicator *comm, CudaMe
                             para->getParH(level)->recvProcessNeighborY[i].rankNeighbor);
     }
     /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-    ////start non blocking MPI send
-    //for (unsigned int i = 0; i < (unsigned int)(para->getNumberOfProcessNeighborsY(level, "send")); i++)
-    //{
-    //    comm->nbSendDataGPU(para->getParH(level)->sendProcessNeighborY[i].f[0],
-    //                        para->getParH(level)->sendProcessNeighborY[i].numberOfFs,
-    //                        para->getParH(level)->sendProcessNeighborY[i].rankNeighbor);
-    //}
-    /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-    ////Waitall
-    //if (0 < (unsigned int)(para->getNumberOfProcessNeighborsY(level, "send")))
-    //{
-    //    comm->waitallGPU();
-    //}
-    /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
     // wait for memcopy device to host to finish before sending data
     if (para->getUseStreams())
         cudaStreamSynchronize(stream);
@@ -279,20 +251,6 @@ void exchangeCollDataZGPU27(Parameter *para, vf::gpu::Communicator *comm, CudaMe
                             para->getParH(level)->recvProcessNeighborZ[i].rankNeighbor);
     }
     /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-    ////start non blocking MPI send
-    //for (unsigned int i = 0; i < (unsigned int)(para->getNumberOfProcessNeighborsZ(level, "send")); i++)
-    //{
-    //    comm->nbSendDataGPU(para->getParH(level)->sendProcessNeighborZ[i].f[0],
-    //                        para->getParH(level)->sendProcessNeighborZ[i].numberOfFs,
-    //                        para->getParH(level)->sendProcessNeighborZ[i].rankNeighbor);
-    //}
-    /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-    ////Waitall
-    //if (0 < (unsigned int)(para->getNumberOfProcessNeighborsZ(level, "send")))
-    //{
-    //    comm->waitallGPU();
-    //}
-    /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
     // wait for memcopy device to host to finish before sending data
     if (para->getUseStreams())
         cudaStreamSynchronize(stream);