Experimental investigation of high-temperature water flow boiling characteristics in plate-fin heat exchanger for nuclear cooling

With the development of space nuclear reactors, the transmission and emission of a large amount of waste heat in space are inevitable. Because of its large heat transfer, clean nature, and safe working medium, flow boiling of high-temperature water is ideal for space applications. This study focuses on high-temperature heat dissipation and experiments on the flow boiling heat transfer of high-temperature water. The steady-state operation characteristics of high-temperature water flow boiling heat transfer in the operating temperature range of 100–250 °C are studied with an emphasis on the variations in heat exchanger efficiency (HEE), heat transfer power (HTP), liquid-side outlet quality (LSOQ) of the high-temperature heat exchanger, and two-phase heat transfer coefficient (HTC). The HTP can be improved to a peak of 16 kW under a moderate air mass flow rate, and the LSOQ can be increased to approximately 0.95. The maximum HTC in this system could reach approximately 2100 W/(m²*K), which offers significant design guidance for the high-temperature water flow boiling system.