Development of the engine began in the 2000s, along with its sibling, the smallerYF-115, which would power the upper stages of theLong March 6 andLong March 7 rockets.[7][8][9] Testing was directed by the China National Space Administration (CNSA) commencing in 2005. Development works are mainly carried out by the Xi'an Aerospace Propulsion Institute. The engine had its first 300 seconds test fire in November 2007.[10]
A high efficiency/high thrust environmentally-friendly rocket engine was always an objective withinProgramme 863 in the 1980s; however, Chinese industry was not mature enough at that time to produce such a rocket until they obtainedRD-120s in early 1990 from Russia following the collapse of the USSR.[7]It is the first Chinese rocket engine to adopt the staged-combustion cycle and the most powerful to date. During July 2012 the engine fired for 200 seconds generating 120 t (260,000 lb) of thrust.[11] On May 28, 2012, the National Defense Science and Industry Bureau certified the engine.[12]
The YF-100 is apump-fed oxidizer richstaged combustion rocket engine. It has adjustable thrust and variablemixture ratio. Its preburner burns all theLOX mass flow with a bit ofkerosene to generate hot gas that powers the single turbine. The turbopump is a single-shaft design, with a single-stage oxygen pump and a dual-stage kerosene pump driven by the same turbine. It also has two low-pressure pumps that preventcavitation. This arrangement is very similar to theRD-170 design. The engine has a heat exchanger to heat oxygen gas for LOX tank pressurization, and also supplies high-pressure kerosene as hydraulic fluid for thethrust vector control actuators.[13]
The development required ten years of research, requiring the mastering of 70 key technologies, the development of 50 new materials, and the construction of 61 sets of engines with a combined total of more than 40,000 seconds of ignition time by 2013.[12]
At least five different versions are known to exist.
YF-100 (single-axisTVC): Version for theLM-5 andLM-7 boosters. This version of TVC has a single axis of gimbal.
YF-100 (dual-axis TVC): Version for theLM-7 core. This version TVC has a dual-axis gimbal.
YF-100GBI: A version used on theLM-6. Due to the rocket's single nozzle, a dual-axis gimbal can not control the rocket's roll. Therefore, this version of the engine diverts a portion of the preburner exhaust through two roll control nozzles on opposite sides of the launch vehicle at the expense of losing 0.30% of thrust and 0.79% ofisp while theO/F ratio is increased by 0.12%.[14]
^"中国新型120吨液氧煤油火箭发动机已经试车成功" [China's new 120 tons of liquid oxygen kerosene rocket engine has been successfully fired] (in Chinese). 2005-11-09. Retrieved2015-07-02.
