Complete success! Key technology breakthroughs

The reporter learned from the Sixth Academy of China Aerospace Science and Technology Corporation on the 26th that China's first high-altitude pump-swinging high-thrust liquid oxygen-kerosene engine recently carried out a 300-second long-range test run and was a complete success.

The engine has the characteristics of high specific impulse and low starting inlet pressure, and will be used in the second-stage power unit of my country's new generation manned carrier rocket.

Video source: Institute 165 of the Sixth Academy of China Aerospace Science and Technology Corporation

It is reported that since September 28, this engine has completed three test runs totaling 650 seconds, with three victories. The three test runs successfully obtained the main working characteristics of this type of engine, and the various indicators of the engine basically met the overall requirements, indicating that the key technology of this type of engine has been broken through, laying a solid foundation for the smooth advancement of the development of my country's new generation of manned rocket engineering.

At the same time, this test run also indicates that the engine development team has fully mastered the technology of large-size titanium alloy nozzle extension section.

The large-size titanium alloy nozzle extension scheme is a core key technology of the high-altitude pump-swing large-thrust liquid oxygen-kerosene engine, and it is also the first application of a large-size regenerative cooling titanium alloy nozzle in a model. Compared with the traditional copper-steel nozzle, it has the outstanding advantage of light weight, which can greatly improve the engine thrust-to-weight ratio, but it also brings challenges such as easy deformation, difficult cooling, and difficult brazing. After 5 years of hard work, the research and development team has successively broken through a number of key technologies such as the design, forming, dissimilar metal brazing, and titanium-titanium brazing of the large-size titanium alloy nozzle extension, turning the drawings into reality. In this test run, the scheme successfully passed the 105% high-operating condition and high-mixing ratio assessment, and was also equipped with a newly developed high-performance kerosene.

Low inlet pressure starting technology is another key technology of the high-altitude pump-swing high-thrust liquid oxygen-kerosene engine. The development team adhered to the "small steps and fast progress" development strategy, gradually lowered the assessment indicators in the three hot tests of the engine, taking into account the development progress and risk control, so that the technology can be further verified.