Enhanced Cooling of a Liquid-Fueled Rocket Thrust Chamber by Metal Foams

摘要

As human beings pursue the deeper space exploration, advanced propulsion systems that deliver super performance and possess increased durability for the next generation spacecraft will be needed, despite current limitations on materials. A promising technology is to fill the current open cooling channels with open-cell metal foams to drastically enhance the cooling of the thrust chamber. After applying the methods developed for the feasibility evaluation, it is found that under equal pressure drop and coolant mass flow rate, the actual amount of increase in the heat transfer coefficient for the foamed channel over the open channel is approximately the same for any given pressure drop, while the percent heat transfer coefficient increase actually decreases with increasing pressure drop from 99% at 841 kPa/m to 48% at 3090 kPa/m. It is also shown that under equal pressure drop and coolant mass flow rate in an actual rocket condition, the heat transfer coefficient of the foamed channel is 49581 W/m~2 K, which is more than 110% enhancement, compared with 23464 W/m~2 K for the open channel. That means that, under the same pressure drop and mass flow rate, the foamed channel has the capability to significantly enhance the cooling for the rocket engine thrust chamber.