A spray cooling system for transverse evaporative spray cooling in a narrow gap which may generally include a mixing zone, a converging zone, a cooling conduit, and a re-circulation conduit. The spray cooling system in some of its embodiments, provides among other things, a feed system for narrow gap evaporative spray cooling, a method for reducing the pressure gradient across the surface from which heat is to be transferred and a housing system which utilizes a baffle to separate the cooling conduit from a re-circulation conduit and to re-circulate vapor to the entry of the cooling conduit.