Smoothing surface

I am hoping somebody can help with some modelling I am doing.
I have several hollow aerofoil sections with open ends which I wish to make smoother. The reason for this is I intend to scale it up for printing and I wish the surface to be very smooth yet retain the edges on the trailing edge and also the straight joints between the sections.
Can anybody help.
Below is one of the sections to show what I mean.


Could try creating a new structure suitable for subdivision, and use shrinkwrap modifier to make it adhere to the surfaces of that one. Then hold the edges with edge creasing or perimeter edge loops and have subdivision surfaces smooth the rest.