diff --git a/dart/src/wTimeSolver.cpp b/dart/src/wTimeSolver.cpp
index ac2f4cd9214938f805ee1069b07509d8562c56c5..fcd307833bb2c5580030b6e7fed1e706e58fe462 100644
--- a/dart/src/wTimeSolver.cpp
+++ b/dart/src/wTimeSolver.cpp
@@ -82,17 +82,18 @@ int TimeSolver::Integration(size_t iPoint, BLRegion *bl)
     double CFL = CFL0;
     unsigned int itFrozenJac = itFrozenJac0;
     double timeStep = SetTimeStep(CFL, dx, bl->invBnd->GetVt(iPoint));
-    Matrix<double, 5, 5> IMatrix;
-    IMatrix = Matrix<double, 5, 5>::Identity() / timeStep;
+    //MatrixXd IMatrix(5,5);
+    MatrixXd IMatrix(5,5);
+    IMatrix = MatrixXd::Identity(5,5) / timeStep;
 
     /* Initial system residuals */
 
-    Vector<double, 5> SysRes = SysMatrix->ComputeFluxes(iPoint, bl);
+    VectorXd SysRes = SysMatrix->ComputeFluxes(iPoint, bl);
     double normSysRes0 = SysRes.norm();
     double normSysRes = normSysRes0;
 
-    Matrix<double, 5, 5> JacMatrix;
-    Vector<double, 5> slnIncr;
+    MatrixXd JacMatrix(5,5);
+    VectorXd slnIncr(5);
 
     nErrors = 0;                 // Number of errors encountered
     unsigned int innerIters = 0; // Inner (non-linear) iterations
@@ -127,7 +128,7 @@ int TimeSolver::Integration(size_t iPoint, BLRegion *bl)
             SysRes = SysMatrix->ComputeFluxes(iPoint, bl);
             CFL = 1.0;
             timeStep = SetTimeStep(CFL, dx, bl->invBnd->GetVt(iPoint));
-            IMatrix = Matrix<double, 5, 5>::Identity() / timeStep;
+            IMatrix = MatrixXd::Identity(5,5) / timeStep;
             normSysRes = (SysRes + slnIncr / timeStep).norm();
             itFrozenJac = 1;
             std::cout << "normSysRes is nan " << std::endl;
@@ -143,7 +144,7 @@ int TimeSolver::Integration(size_t iPoint, BLRegion *bl)
 
         CFL = std::max(CFL0 * pow(normSysRes0 / normSysRes, 0.7), 0.1);
         timeStep = SetTimeStep(CFL, dx, bl->invBnd->GetVt(iPoint));
-        IMatrix = Matrix<double, 5, 5>::Identity() / timeStep;
+        IMatrix = MatrixXd::Identity(5,5) / timeStep;
 
         innerIters++;
     } // End while (innerIters < maxIt)
diff --git a/dart/src/wViscFluxes.cpp b/dart/src/wViscFluxes.cpp
index 5d0e0a19e3eca0f44194849127734cde70e7cb52..86269781ba7ab35260ee7d3970705db84bb8f188 100644
--- a/dart/src/wViscFluxes.cpp
+++ b/dart/src/wViscFluxes.cpp
@@ -23,7 +23,7 @@ ViscFluxes::~ViscFluxes()
     std::cout << "~ViscFluxes()\n";
 } // end ~ViscFluxes
 
-Vector<double, 5> ViscFluxes::ComputeFluxes(size_t iPoint, BLRegion *bl)
+VectorXd ViscFluxes::ComputeFluxes(size_t iPoint, BLRegion *bl)
 {
     unsigned int nVar = bl->GetnVar();
     std::vector<double> u(nVar, 0.);
@@ -34,7 +34,7 @@ Vector<double, 5> ViscFluxes::ComputeFluxes(size_t iPoint, BLRegion *bl)
     return BLlaws(iPoint, bl, u);
 }
 
-Matrix<double, 5, 5> ViscFluxes::ComputeJacobian(size_t iPoint, BLRegion *bl, Vector<double, 5> &sysRes, double eps)
+MatrixXd ViscFluxes::ComputeJacobian(size_t iPoint, BLRegion *bl, VectorXd &sysRes, double eps)
 {
 
     unsigned int nVar = bl->GetnVar();
@@ -58,7 +58,7 @@ Matrix<double, 5, 5> ViscFluxes::ComputeJacobian(size_t iPoint, BLRegion *bl, Ve
     return JacMatrix;
 }
 
-Vector<double, 5> ViscFluxes::BLlaws(size_t iPoint, BLRegion *bl, std::vector<double> u)
+VectorXd ViscFluxes::BLlaws(size_t iPoint, BLRegion *bl, std::vector<double> u)
 {
     unsigned int nVar = bl->GetnVar();
 
diff --git a/dart/src/wViscFluxes.h b/dart/src/wViscFluxes.h
index 1c9867f34e29f1b40c617b0a5d4d9ae8f36ccfc1..e6881f72e11f897db1c630ccb46b70c5c4d22ce7 100644
--- a/dart/src/wViscFluxes.h
+++ b/dart/src/wViscFluxes.h
@@ -18,11 +18,11 @@ private:
 public:
     ViscFluxes(double _Re);
     ~ViscFluxes();
-    Eigen::Vector<double, 5> ComputeFluxes(size_t iPoint, BLRegion *bl);
-    Eigen::Matrix<double, 5, 5> ComputeJacobian(size_t iPoint, BLRegion *bl, Eigen::Vector<double, 5> &sysRes, double eps);
+    Eigen::VectorXd ComputeFluxes(size_t iPoint, BLRegion *bl);
+    Eigen::MatrixXd ComputeJacobian(size_t iPoint, BLRegion *bl, Eigen::VectorXd &sysRes, double eps);
 
 private:
-    Eigen::Vector<double, 5> BLlaws(size_t iPoint, BLRegion *bl, std::vector<double> u);
+    Eigen::VectorXd BLlaws(size_t iPoint, BLRegion *bl, std::vector<double> u);
     double AmplificationRoutine(double hk, double ret, double theta) const;
 };
 } // namespace dart