J-20 Uses WS-15

J-20 proves that it uses WS-15 engines as there are no grooves on the nozzles of its engines.

The nozzle of Russian AL-31F engine used on J-20 prototypes. There are two groves on the nozzle

Engine with no grooves on it

 

WS-15 is much more powerful than AL-31F. The AL-31F’s nozzle has shrunk so that the speed of smoke is much higher than that of the WS-15 with nozzle not shrunk while they produce similar thrust for the J-20

Aero engine development:

Mil.news.sina.com.cn  in report reveals that the temperature before turbine is 1,474 degree Celsius in WS-15, the highest in the world. No wonder WS-15 is much more powerful than AL-31F.
Its reliability lies between Western and Russian ones with a life of 900 hours longer than AL-31F.
Since the engine problem has been solved, J-20 can be regarded as a capable modern stealth fighter as it has satisfactory electronics and stealth shape.