I am not new to solidworks but I am to the flow simulation. I used the trace tool to sketch an airfoil and I then modified some of the contours. I was also careful to find and delete any loose segments. I then extruded it 3 in. When I attempted to run the simulation the watertight error comes up. I looked up examples of how to use the lid function; however, those are of all very obvious holes. How can I fix this? I also attached the model if that helps.