Added some asserts, typo fix in pe coupling

src/pe_coupling/mapping/BodyBBMapping.cpp

@@ -57,7 +57,7 @@ CellInterval getCellBB( const pe::ConstBodyID body, const IBlock & block, Struct
       // then determine the cell bounding box of the intersection
       blockStorage.getCellBBFromAABB( cellBB, body->getAABB().getIntersection( extendedBlockAABB ), level );
 
-      // if infinte body does not intersect with the extended block AABB, return an empty interval
+      // if infinite body does not intersect with the extended block AABB, return an empty interval
       if( cellBB.empty() ) return CellInterval();
    }
 

src/pe_coupling/momentum_exchange_method/BodyMapping.h

@@ -123,6 +123,9 @@ private:
 
       CellInterval cellBB = getCellBB( body, *block, *blockStorage_, flagField->nrOfGhostLayers() );
 
+      WALBERLA_ASSERT_LESS_EQUAL(body->getLinearVel().length(), real_t(1),
+            "Velocity is above 1 (" << body->getLinearVel() << "), which violates the assumption made in the getCellBB() function. The coupling might thus not work properly. Body:\n" << *body);
+
       Vector3<real_t> startCellCenter = blockStorage_->getBlockLocalCellCenter( *block, cellBB.min() );
 
       real_t cz = startCellCenter[2];
@@ -157,6 +160,9 @@ private:
                   }
                   // let pointer from body field point to this body
                   (*bodyField)(x,y,z) = body;
+
+                  WALBERLA_ASSERT(isFlagSet( cellFlagPtr, obstacle ), "Flag mapping incorrect for body\n" << *body );
+                  WALBERLA_ASSERT_EQUAL((*bodyField)(x,y,z), body, "Body field does not point to correct body\n" << *body << ".");
                }
                else
                {

src/pe_coupling/momentum_exchange_method/restoration/PDFReconstruction.h

@@ -108,7 +108,7 @@ private:
                if (isFlagSet(flagField->get(x,y,z), formerObstacle)) {
                   boundaryHandling->setDomain( fluid, x, y, z );
                   removeFlag( flagField->get(x,y,z), formerObstacle );
-                  (*bodyField)(x,y,z) = NULL;
+                  (*bodyField)(x,y,z) = nullptr;
                }
             }
          }