A water-cooled tube-in-tube gas cooler was designed in this paper

and experimental researches on it were conducted. A triple tube is equipped in the gas cooler with CO2 in the inner tubes and water between inner and outer tubes. Experimental investigations were done about the effect of CO2 mass flow rate

inlet pressure and cooling water temperature on heat transfer coefficient

heat transfer and heat exchanger efficiency. The results show that both heat transfer coefficient and heat transfer firstly increase and then decrease while CO2 mass flow rate increases

and heat exchanger efficiency reduce gradually when CO2 mass flow rate increases. In the same CO2 mass flow rate

heat transfer coefficient

heat transfer and heat exchanger efficiency increase with the increase of CO2 inlet pressure and decrease while cooling water temperature increases.