Recent internet photos show that a new version of the WS-10 “Taihang” engine has been equipped with two Chinese fighter jets – J-11B and J-16. The most striking feature of the engine is that it is equipped with a newly designed exhaust nozzle, of which the longer convergence-expansion section is closer to the GE F100 engine fuel nozzle in shape.
Before this, the most interesting design feature of the domestic “Taihang” engine visible to the naked eye was its double-layer ejector nozzle. This fuel nozzle may be affected by the Russian D30-F6 afterburner turbofan engine. It has internal and external bilateral convergence-expanding fish scales. The fish scales are linked by a connecting rod, and there is a circle of cold air ejection channels between the two, according to analyst Bai Zhandao.
With the large-scale service of WS-10 engines, it has gradually matured in the accumulation of massive flight hours, and the subsequent improvement of the engine is also on the agenda. In addition to further increase in thrust and reliability, the focus of the follow-up improvement of “Taihang” is to improve the design of its exhaust nozzle.
Bai Zhandao speculates that the new WS-10 engine has probably abandoned the iconic double-layered fuel nozzle for a more mainstream single-layered fuel nozzle design thanks to new heat-resistant materials, so it has a longer convergent-expanding section in appearance, which is completely different from the old Taihang engine.
Under the premise of meeting reliability and longevity, the new nozzle greatly simplifies the structure and facilitates maintenance due to the elimination of many fish scales and connecting rods, and the single-layer design can also reduce the weight of the nozzle and improve the overall thrust-to-weight ratio of the engine, allowing China’s homemade fighters to have higher maneuverability. It is expected that the “Taihang” engines for J-20 stealth fighters will soon use the stealthy serrated fuel nozzle based on the new fuel nozzle, after J-20’s maiden flight with Taihang WS-10 engines in 2017.