A heat and mass transfer system configured to be a passive system using gravitational force to form a thin liquid film flow on an outer surface of a flow distribution head and downstream conduit member to subject the thin liquid film to heat transfer mediums. The at least partially spherical flow distribution head creates a uniform thin flow of liquid on the outer surface increasing the efficiency of the heat and mass transfer system. The heat and mass transfer system may include a heat transfer medium supply system in fluid communication with internal aspects of the downstream conduit such that a heat transfer medium flows within the downstream conduit while the liquid film flows on the outer surface of the downstream conduit. Rather than conventional sheet flow on inner surfaces of a conduit, the flow distribution head enables sheet flow to be formed on an outside surface of a component.