diff --git a/cpu/VirtualFluidsCore/CoProcessors/AverageValuesCoProcessor.cpp b/cpu/VirtualFluidsCore/CoProcessors/AverageValuesCoProcessor.cpp
index 7c5cdf72614a348660d25cfc2d73b8c75442ef8a..474703728481f85b7fcddbf4bf7e6f33d2bfd52d 100644
--- a/cpu/VirtualFluidsCore/CoProcessors/AverageValuesCoProcessor.cpp
+++ b/cpu/VirtualFluidsCore/CoProcessors/AverageValuesCoProcessor.cpp
@@ -274,7 +274,7 @@ void AverageValuesCoProcessor::addData(const SPtr<Block3D> block)
 	//int ghostLayerWidth = kernel->getGhostLayerWidth();
 
 	//knotennummerierung faengt immer bei 0 an!
-	int SWB,SEB,NEB,NWB,SWT,SET,NET,NWT;
+	unsigned int SWB,SEB,NEB,NWB,SWT,SET,NET,NWT;
 
 	int minX1 = 0;
 	int minX2 = 0;
diff --git a/cpu/VirtualFluidsCore/CoProcessors/AverageValuesCoProcessor.h b/cpu/VirtualFluidsCore/CoProcessors/AverageValuesCoProcessor.h
index 65ef5721bff343e45cefd28cedf7047a186c4aa2..f3931c4be90997784816303889bfa6efa317c0b6 100644
--- a/cpu/VirtualFluidsCore/CoProcessors/AverageValuesCoProcessor.h
+++ b/cpu/VirtualFluidsCore/CoProcessors/AverageValuesCoProcessor.h
@@ -48,7 +48,7 @@ protected:
 
 private:
 	std::vector<UbTupleFloat3> nodes;
-	std::vector<UbTupleInt8> cells;
+	std::vector<UbTupleUInt8> cells;
 	std::vector<std::string> datanames;
 	std::vector<std::vector<double> > data; 
 	std::vector<std::vector<SPtr<Block3D>> > blockVector;
diff --git a/cpu/VirtualFluidsCore/CoProcessors/QCriterionCoProcessor.cpp b/cpu/VirtualFluidsCore/CoProcessors/QCriterionCoProcessor.cpp
index 291eb31e9b56a4b2dab561548e5b4ca3de7ecb00..6378c3b7e96f8781f9ae0cf097bce88b96391234 100644
--- a/cpu/VirtualFluidsCore/CoProcessors/QCriterionCoProcessor.cpp
+++ b/cpu/VirtualFluidsCore/CoProcessors/QCriterionCoProcessor.cpp
@@ -116,7 +116,7 @@ void QCriterionCoProcessor::addData(const SPtr<Block3D> block)
 	SPtr<BCArray3D> bcArray = kernel->getBCProcessor()->getBCArray();          
 	SPtr<DistributionArray3D> distributions = kernel->getDataSet()->getFdistributions();  
 
-	int SWB,SEB,NEB,NWB,SWT,SET,NET,NWT;
+	unsigned int SWB,SEB,NEB,NWB,SWT,SET,NET,NWT;
 
 	int minX1 = 0;
 	int minX2 = 0;
diff --git a/cpu/VirtualFluidsCore/CoProcessors/QCriterionCoProcessor.h b/cpu/VirtualFluidsCore/CoProcessors/QCriterionCoProcessor.h
index 52bb2860067d779781299312c11ad70d05cf4a64..1a1f53d9ad0c2391fc43ab08117ea2a2a95ac0b4 100644
--- a/cpu/VirtualFluidsCore/CoProcessors/QCriterionCoProcessor.h
+++ b/cpu/VirtualFluidsCore/CoProcessors/QCriterionCoProcessor.h
@@ -48,7 +48,7 @@ protected:
 private:
 	void init();
 	std::vector<UbTupleFloat3> nodes;
-	std::vector<UbTupleInt8> cells;
+	std::vector<UbTupleUInt8> cells;
 	std::vector<std::string> datanames; //only one entry for QKrit-CoProcessor: Q
 	std::vector<std::vector<double> > data; 
 	std::vector<std::vector<SPtr<Block3D> > > blockVector;
diff --git a/cpu/VirtualFluidsCore/CoProcessors/TimeAveragedValuesCoProcessor.cpp b/cpu/VirtualFluidsCore/CoProcessors/TimeAveragedValuesCoProcessor.cpp
index c1a3b76f2c08e8750d8805a8c6c3ba0ad83c43e4..79dafae063b64b8dbbfa62dc6e6c1d5e2e0173f6 100644
--- a/cpu/VirtualFluidsCore/CoProcessors/TimeAveragedValuesCoProcessor.cpp
+++ b/cpu/VirtualFluidsCore/CoProcessors/TimeAveragedValuesCoProcessor.cpp
@@ -285,7 +285,7 @@ void TimeAveragedValuesCoProcessor::addData(const SPtr<Block3D> block)
    //int ghostLayerWidth = kernel->getGhostLayerWidth();
 
    //knotennummerierung faengt immer bei 0 an!
-   int SWB, SEB, NEB, NWB, SWT, SET, NET, NWT;
+   unsigned int SWB, SEB, NEB, NWB, SWT, SET, NET, NWT;
 
    int minX1 = iMinC;
    int minX2 = iMinC;
diff --git a/cpu/VirtualFluidsCore/CoProcessors/TimeAveragedValuesCoProcessor.h b/cpu/VirtualFluidsCore/CoProcessors/TimeAveragedValuesCoProcessor.h
index 844beb9ffc2c5e2c7fff548157dd46c99341b295..9a9df0f8041647918d9bf51fbf3b1f3543faf66c 100644
--- a/cpu/VirtualFluidsCore/CoProcessors/TimeAveragedValuesCoProcessor.h
+++ b/cpu/VirtualFluidsCore/CoProcessors/TimeAveragedValuesCoProcessor.h
@@ -69,7 +69,7 @@ protected:
 private:
     SPtr<Communicator> comm;
    std::vector<UbTupleFloat3> nodes;
-   std::vector<UbTupleInt8> cells;
+   std::vector<UbTupleUInt8> cells;
    std::vector<std::string> datanames;
    std::vector<std::vector<double> > data;
    std::vector<std::vector<SPtr<Block3D> > > blockVector;
diff --git a/cpu/VirtualFluidsCore/CoProcessors/TurbulenceIntensityCoProcessor.cpp b/cpu/VirtualFluidsCore/CoProcessors/TurbulenceIntensityCoProcessor.cpp
index 3ca28306cad61f149302975f06d8ea80d6cb510a..e3a4f4ee90df1c15e279bd0d3982dd8f7231802e 100644
--- a/cpu/VirtualFluidsCore/CoProcessors/TurbulenceIntensityCoProcessor.cpp
+++ b/cpu/VirtualFluidsCore/CoProcessors/TurbulenceIntensityCoProcessor.cpp
@@ -124,7 +124,7 @@ void TurbulenceIntensityCoProcessor::addData(const SPtr<Block3D> block)
    //int ghostLayerWidth = kernel->getGhostLayerWidth();
 
    //knotennummerierung faengt immer bei 0 an!
-   int SWB,SEB,NEB,NWB,SWT,SET,NET,NWT;
+   unsigned int SWB,SEB,NEB,NWB,SWT,SET,NET,NWT;
 
    int minX1 = 0;
    int minX2 = 0;
diff --git a/cpu/VirtualFluidsCore/CoProcessors/TurbulenceIntensityCoProcessor.h b/cpu/VirtualFluidsCore/CoProcessors/TurbulenceIntensityCoProcessor.h
index 811bf808da1128b328432578f6eb86422490f2db..2fd39b030af0ae36e9e2d935cf1dca1d5ede8480 100644
--- a/cpu/VirtualFluidsCore/CoProcessors/TurbulenceIntensityCoProcessor.h
+++ b/cpu/VirtualFluidsCore/CoProcessors/TurbulenceIntensityCoProcessor.h
@@ -28,7 +28,7 @@ protected:
 private:
    void init();
    std::vector<UbTupleFloat3> nodes;
-   std::vector<UbTupleInt8> cells;
+   std::vector<UbTupleUInt8> cells;
    std::vector<std::string> datanames;
    std::vector<std::vector<double> > data; 
    std::vector<std::vector<SPtr<Block3D> > > blockVector;
diff --git a/cpu/VirtualFluidsCore/CoProcessors/WriteBoundaryConditionsCoProcessor.cpp b/cpu/VirtualFluidsCore/CoProcessors/WriteBoundaryConditionsCoProcessor.cpp
index d4b4df1d02b7af997fd332abf6559fe82ec79556..d74e1edf3c453ae0efd28355552f0bf55580cb82 100644
--- a/cpu/VirtualFluidsCore/CoProcessors/WriteBoundaryConditionsCoProcessor.cpp
+++ b/cpu/VirtualFluidsCore/CoProcessors/WriteBoundaryConditionsCoProcessor.cpp
@@ -130,7 +130,7 @@ void WriteBoundaryConditionsCoProcessor::addDataGeo(SPtr<Block3D> block)
    SPtr<BCArray3D> bcArray = kernel->getBCProcessor()->getBCArray();
 
    //knotennummerierung faengt immer bei 0 an!
-   int SWB, SEB, NEB, NWB, SWT, SET, NET, NWT;
+    unsigned int SWB, SEB, NEB, NWB, SWT, SET, NET, NWT;
 
    int minX1 = 0;
    int minX2 = 0;
diff --git a/cpu/VirtualFluidsCore/CoProcessors/WriteBoundaryConditionsCoProcessor.h b/cpu/VirtualFluidsCore/CoProcessors/WriteBoundaryConditionsCoProcessor.h
index bbbca20b01e83dbebc8e97d1e51f00cdf722a079..407d56b3ee67d6986b7a4deed8ecdd8473ac5063 100644
--- a/cpu/VirtualFluidsCore/CoProcessors/WriteBoundaryConditionsCoProcessor.h
+++ b/cpu/VirtualFluidsCore/CoProcessors/WriteBoundaryConditionsCoProcessor.h
@@ -31,7 +31,7 @@ protected:
 
 private:
    std::vector<UbTupleFloat3> nodes;
-   std::vector<UbTupleInt8> cells;
+   std::vector<UbTupleUInt8> cells;
    std::vector<std::string> datanames;
    std::vector<std::vector<double> > data;
    std::string path;
diff --git a/cpu/VirtualFluidsCore/CoProcessors/WriteMacroscopicQuantitiesCoProcessor.cpp b/cpu/VirtualFluidsCore/CoProcessors/WriteMacroscopicQuantitiesCoProcessor.cpp
index 5ee51000950a8eed7745fca0131236cd0d4afa2f..25ce8cd39c2c59d8ed764b56f3dbc65d29f72065 100644
--- a/cpu/VirtualFluidsCore/CoProcessors/WriteMacroscopicQuantitiesCoProcessor.cpp
+++ b/cpu/VirtualFluidsCore/CoProcessors/WriteMacroscopicQuantitiesCoProcessor.cpp
@@ -139,7 +139,7 @@ void WriteMacroscopicQuantitiesCoProcessor::addDataMQ(SPtr<Block3D> block)
    LBMReal vx1,vx2,vx3,rho;
 
    //knotennummerierung faengt immer bei 0 an!
-   int SWB,SEB,NEB,NWB,SWT,SET,NET,NWT;
+   unsigned int SWB,SEB,NEB,NWB,SWT,SET,NET,NWT;
 
    if(block->getKernel()->getCompressible())
    {
diff --git a/cpu/VirtualFluidsCore/CoProcessors/WriteMacroscopicQuantitiesCoProcessor.h b/cpu/VirtualFluidsCore/CoProcessors/WriteMacroscopicQuantitiesCoProcessor.h
index ca6e2fcb41b3975ba22ca8f25e8cd031881e7177..e112fc10ab9b4b176b77099cc5f7cd44a7717fc4 100644
--- a/cpu/VirtualFluidsCore/CoProcessors/WriteMacroscopicQuantitiesCoProcessor.h
+++ b/cpu/VirtualFluidsCore/CoProcessors/WriteMacroscopicQuantitiesCoProcessor.h
@@ -35,7 +35,7 @@ protected:
 private:
    void init();
    std::vector<UbTupleFloat3> nodes;
-   std::vector<UbTupleInt8> cells;
+   std::vector<UbTupleUInt8> cells;
    std::vector<std::string> datanames;
    std::vector<std::vector<double> > data; 
    std::string path;