MP bug fix and additional interpolation warning details

Author: joshkellyjak

Common/src/interface_interpolation/CMixingPlane.cpp

@@ -146,7 +146,14 @@ void CMixingPlane::SetTransferCoeff(const CConfig* const* config) {
                     // Calculate interpolation coefficient
                     coeff = (spanValuesTarget[iSpanTarget] - spanValuesDonor[kSpan]) / 
                             (spanValuesDonor[kSpan + 1] - spanValuesDonor[kSpan]);
-                    if (((coeff < 0) || (coeff > 1)) && (rank == MASTER_NODE)) cout << "Warning! Target spans exist outside the bounds of donor spans!" << endl;
+                    if (((coeff < 0) || (coeff > 1)) && (rank == MASTER_NODE)){
+                        cout << "Warning! Target spans exist outside the bounds of donor spans!" <<  endl;
+                        cout << "Target span " << iSpanTarget << " <- " << kSpan << " coeff = " << coeff << endl;
+                        if (iSpanTarget < nSpanTarget/2) cout << "This is likely an issue at the hub." << endl;
+                        if (iSpanTarget > nSpanTarget/2) cout << "This is likely an issue at the shroud." << endl;
+                        cout << "Setting coeff = 0.0" << endl;
+                        coeff = 0.0;
+                    }
                     targetSpan.donorSpan = kSpan;
                     targetSpan.coefficient = coeff;
                     break;