At the test site, whether it was Xiao Weiguo, Messerschmidt or others, they all felt that this test should be a success! The first stage of the six-hour test is the most grinding time, because at this time everyone does not know whether there will be problems in this process, everything has to wait for the end of the 6 hours, the wind and thunder engine cools down, and then the engine is disassembled for careful inspection to know whether the improved design has worked. Even these 6 hours are not completely certain, because there are still 15 6-hour trials! The whole process was long and arduous!

After two hours of testing, Messerschmidt finally couldn't help but say: "The jet engine test is really complicated, and this long-lasting test is torture enough!" Hopefully, this time the Thunder Jet Engine will stand the test! ”

Xiao Weiguo nodded and said, "That's true!" A jet engine is inherently a complex product. In particular, the long-term test is related to the life of the wind and thunder engine, and we can't help but take it seriously! The life of an aero engine refers to the duration of the normal operation of the engine on the aircraft, and essentially refers to the time or the number of working cycles when the main structural parts can work safely and reliably before the wear, creep deformation, stress fracture or high and low cycle fatigue cracks cause the failure of the parts. If the engine life is too short, it will cause a huge waste of resources, and a long life will lead to serious flight safety accidents in use. In addition to the long-lasting test run of the engine, it is also necessary to slowly form a series of life determination and life control technologies for aero engines through long-term technical exploration, and play a role in the development and use of aero engines in the future. ”

Messerschmidt said: "This is only the first flip life of the engine, so how to determine the total working life of the engine?" ”

Xiao Weiguo said: "The total working life of the engine refers to the total working hours of the engine under specified conditions, from the beginning of use to the final scrapping. It is mainly determined by the total operating time, cycle life, i.e. low cycle fatigue times, and large state operating time. The total working life of the current piston engine is generally given in hours, so the jet engine can also be used in hours, but the engine developed in the later period can also be given with a low cycle fatigue number. For engines that are allowed to be overhauled during the total working life, the total working life of the whole machine can be sustained because almost all of its parts can be replaced. Therefore, in life management, the use of total life indicators is not mainly based on the consideration of engine safety and reliability, but more due to the need for economy, management and technology upgrading. Jet engines can also be scrapped after one overhaul or two overhauls, if they are only used for more than 100 hours or more than 200 hours. It's really wasteful, and many users can't afford such an expensive cost. “

After listening to Xiao Weiguo's explanation, the designers and engineers of the Fenglei series engine development team have a deeper understanding of the life of jet engines. It turns out that jet engines, like piston engines, can be rebuilt to extend their life again.

Xiao Weiguo continued: "Of course, the most direct and concise and effective way to extend life is still to use the bench for long-lasting test and leading use assessment. Because the structural strength of the wind and thunder series engine parts is guaranteed by the empirical safety factor method, the static strength reserve coefficient is larger, the structural design is biased towards safety, the life value given is relatively conservative, and there is a large life potential, so the life of the wind and thunder series engine can reasonably extend the service life, that is, the first life is re-determined after the first life! ”

"However, the safety factor method design does not reflect the load of the component under actual operating conditions, and we do not have the technical data to design and test the life verification, after all, we are the first company in the world to develop a jet engine. Therefore, it is an effective and feasible method to use the combination of long-term test test assessment and verification of the bench and leading use when the life extension of the wind and thunder series is fixed. The long-term test assessment is a necessary prerequisite for the extension of engine life. Before the long-term test assessment of the bench, it is usually necessary to analyze the fault conditions in use and carry out the necessary local reinforcement treatment on the identified weak links. Through long-term commissioning, the main components are assessed for possible failures during the expected service life. ”

"In the future, we will be conducting a long-term test program with a 1-to-1 hour on the bench and in the field. Due to the complex and changeable load in the actual use of the engine, it is difficult to simulate the engine use task and load cycle realistically only by relying on the long-lasting test spectrum of 1 to 1 hour, especially some motorized loads in use cannot be simulated on the test bench, and some component failures can not be fully exposed. Therefore, the engine after the long-term test must pass the assessment of small batches of leading flight use before approving the new life value. Leading use is to verify the achievability of the life extension goal through the use of life extension engines in small batches on aircraft. In fact, it is to verify whether the engine can be extended to a given life by strengthening the condition monitoring of the leading engine. If the wind and thunder jet engine through the final long-lasting test to determine its first flip life of 150 hours, then after 150 hours of use, you can determine its life extension through the test! ”

Xiao Weiguo explained in detail the method of determining the life extension of the Wind and Thunder series engines, which made everyone feel that there was a feeling of sudden enlightenment in front of them, and success seemed to be beckoning to the Dragon Soul Ordnance Complex! In this way, while discussing the problem of the wind and thunder engine, while waiting for the completion of the first stage of the long test, everyone did not even go to lunch, as if everyone present had forgotten to eat lunch!

Time flies. Six hours later, it's 4 o'clock in the afternoon! The first stage of the long test is finally over! After a period of cooling, the testers began to disassemble the thunderstorm jet engine! Everyone held their breath! Because everyone is afraid to see any damage to engine parts! Fortunately, after the wind and thunder jet engine was improved, it once again withstood the test! After careful inspection and the use of measuring tools, there was no obvious damage to the parts of the prototype of the Thunder Jet Engine after 6 hours of long test, which means that the second stage of the long test can be continued the next day! It only takes 15 6 hours of long testing and there is still no problem in the end. The Wind Thunder jet engine has initially withstood the test of protracted testing! You can enter the next step of the installation test flight!

The Wind Thunder Jet Engine really lived up to expectations, half a month later! It has finally completed the long-term test test! The test results showed that everything was normal. The life of the Wind Thunder jet engine exceeded expectations!

Just after the success of the long-lasting test run of the Thunder jet engine, Xiao Weiguo and Messerschmidt were going to participate in the tank bidding meeting secretly held by the German Ministry of Defense! (To be continued.) )