The Military-industrial Scientific Research System of the Academic Master Chapter 512

Chapter 512 Finally, we can produce turbofans independently!

 Although it is just an improved model, aviation safety is extremely important, and the necessary testing procedures must not be sloppy.

What's more, the utilization rate of new technology in this so-called "Spey reform" is almost more than one-third -

 The first prototype No. 901 modified some unreasonable designs of the high-pressure compressor blades and oil supply part, replaced it with a new domestic oil pump, bearings and gear set, and integrated the original bearing components.

 This reduces the number of components and widens the surge margin.

By this time, although there are still many modifications, they are still minor repairs to the prototype engine.

Not only the performance calibration has not changed, but the core design of the hot end component has also remained original, so the basic performance has not changed much, except that the weight has been reduced by about 75 kilograms.

  But on the second prototype No. 902, which was produced at the end of 1997, the changes were relatively large.

In order to test the effectiveness of the new active cooling technology, Chang Haonan specifically asked technicians from the 606 Institute to modify the engine performance calibration.

By improving combustion efficiency and upgrading aviation fuel, the temperature in front of the turbine has been increased by about 50-60°C, reaching a level close to that of the third-generation turbofan engine.

 The intoxicated expression is slightly abnormal.

At the entrance of the engine assembly workshop of the 410 Factory, Chang Haonan, Zhong Shihong, and Zhang Zhenhua stood side by side, watching the engine that had finally completed the factory's complete machine inspection being slowly installed on the specially designed engine bracket.

 But this second prototype, due to huge improvements in all aspects, the original British parts could no longer adapt to its working condition.

 Shengjing, mid-January morning.

 Especially the processing of air film holes on the inner walls of turbines and combustion chambers.

Not only does the processing of each hole require several more steps than the turbojet 14, but the subsequent grinding and quality inspection also require additional steps.

To this end, the compressor of the second prototype engine was also modified. The blade separation flow active control technology developed during the development of turbofan 10 was used on the 9-12-stage high-pressure compressor blades to reduce the total pressure of the compressor. The ratio increased to around 22-23.

Compared to a dozen accurate round holes, the dustpan-shaped hole with a forward angle developed by Chang Haonan is quite unfriendly to the EDM technology developed by the 410 Factory.

 The design of aeroengines affects the whole body.

However, he still couldn't hold it back and gently stroked the oil pipeline exposed on the outside of the engine casing.

 In order to speed up production, about a quarter of the components of the previous 901 machine were directly assembled using parts imported from the UK.

In short, although Chang Haonan could not wait to start testing this engine that uses a lot of turbofan 10 technology the day after posting the picture, even if the 410 factory specially set aside a production line and carried out production in three shifts 24 hours a day, it would still be It took more than two months to produce the 902 machine.

 It was not until the engine was fixed by the hoisting team and started to be packed in cargo boxes that he reluctantly returned.

“Sibei, after more than 20 years of domestic production, we have finally created an engine that is 100% domestically produced…”

 The metal tail nozzle was bone-chilling, freezing Zhang Zhenhua, who was not mentally prepared.

With the white mist rising in front of him, Zhang Zhenhua said with emotion.

 The temperature is about minus 20℃.

However, since the research and development of the manufacturing process will take time, the electrolytic machining, electron beam welding, precision forging, precision casting and other technologies used in the production and manufacturing of this engine are still at the previous level.

Zhang Zhenhua took two steps forward, stretched out his hand and patted the tail nozzle of the engine twice in mid-air.

 The yield rate is still much lower.

 Hence, all components are newly produced domestically.

During this process, Factory 410 also verified the application of several key new manufacturing technologies such as metal spraying, vacuum heat treatment, trajectory welding, vacuum brazing, and CNC pipe bending, laying the foundation for the next step of manufacturing the turbofan 10.

 “Yeah, but it's a pity it's a little too late...”

Zhong Shihong took out a ballpoint pen and signed his name on the factory slip and responded:

“After the introduction of SPEI, there was a period of vacillation for more than ten years. Now that we have made domestic models, even if their performance is better than the original ones, the prospects are relatively limited…”

 The introduction of Sibei also hides a love-hate relationship between the 410 factory and the 430 factory.

 The former insisted on continuing to develop turbofan 6, while the latter believed that it should start with Spey.

 If I must say it, it was a lose-lose situation in the end.

At this point, it is no longer clear who is who.

 Fortunately, for the generation of Zhong Shihong and Zhang Zhenhua, they don't have many related memories. The smell of gunpowder between the two units has gradually disappeared with the advancement of the Turbofan 10 project and the deepening of R&D collaboration.

 Contradictions fundamentally come from competition in resource allocation.

Now that Chang Haonan has almost increased the scale of China's aerospace industry by an order of magnitude, the difficulty of dividing the cake has naturally been reduced a lot.

Even so, after noticing that the topic between the two people was gradually moving towards the past, he quickly changed the subject:

 “It's useless to talk about the past.”

As he spoke, Chang Haonan also took the pen from Zhong Shihong and signed his name.

The production of the Turbofan 9A prototype is nominally as a technical demonstrator for the Turbofan 10, so the signature of his chief designer is naturally indispensable.

“No matter what, there must be a demand for dozens or hundreds of improved JH-7s, and the turbofan 9A can still make a difference in this regard.”

“It's just a pity that Spey Aircraft converted to combustion. Now the QC130 converted from turbojet 14 to combustion has entered the design finalization stage. The Navy should not accept another gas turbine with similar power..."

After the factory delivery procedures were signed, the staff quickly loaded the neatly packed engine packaging box onto a special Mercedes-Benz semi-trailer.

This car may be the only 100% imported product in the entire Turbofan 10 project.

 The main reason is that everyone is really busy and has no time to build a special engine transport vehicle.

 The finished engine will be transported by this vehicle to Beiling Airport, and then transported by an IL-76 transport aircraft to 624 for necessary ground testing.

“Mr. Chang, what do you think the actual performance of this engine can achieve?”

 Zhang Zhenhua, as the director of the production department, has not been involved much in the field of engine design, so he does not know the specific effects of these upgrades on the turbofan 9A.

 “Don't have too high expectations...”

Chang Haonan shook his head, returned the pen in his hand to Zhong Shihong, and continued to explain:

“The design level of the Spey engine itself is not good. I spent a lot of time adjusting the data of the compressor and combustion chamber, but the matching degree is always average.”

“After all, it is an improved model, and it is impossible to go to great lengths to redesign a core machine, so we can only make do with it.”

 There was some dissatisfaction with the British in his words.

Of course, the two people next to me wouldn't have any objections.

 After all, Mr. Chang's ability is obvious to all, and he is indeed qualified to evaluate him in this way.

“In addition, because at the time of blade production, the multi-arc ion plating equipment in the factory was not yet in place, so the hot-end components had not yet used new coating technology, and the increase in temperature in front of the turbine was relatively limited.”

"Of course, on the other hand, the turbine front temperature of the Spey MK202 itself is already quite high. It is indeed true that the British can use such a high turbine front temperature to design such an engine with mediocre performance... tsk tsk tsk."

At this time, it would be difficult for Zhang Zhenhua and Zhong Shihong to answer the phone.

“Then…how much can some typical paper performance be improved?”

“If it's more specific, we'll have to do bench testing before we know it.”

 At this time, a Jetta King stopped in front of the three people.

 The one driving the car is naturally Zhu Yadan.

Chang Haonan opened the right rear door, turned back to the two people and continued:

“However, according to the performance calibration I did, the thrust at sea level can be increased to about 10,000kg. The total weight of the engine, according to the national standard, should not be higher than 1,750kg.”

 After finishing speaking, he got into the car and signaled that the convoy could set off.

 Only two people were left messy in the wind.

 “This is still called 'don't have high expectations'?”

 Zhang Zhenhua looked at Zhong Shihong next to him with a somewhat stiff movement.

You should know that the sea level afterburning thrust of the Sibei MK202 is 9300kg, the national standard dead weight is as high as 1842kg, and the thrust-to-weight ratio is only 5.05.

 The turbofan 9A directly increases the thrust-to-weight ratio of the engine by nearly 15%!

“As you know, Mr. Chang has always been very demanding on projects.”

Zhong Shihong held up the cotton hat on his head.

 He ​​actually felt it was a bit outrageous, but in front of Zhang Zhenhua, he still maintained his demeanor and did not show any obvious surprise:

 “In short, I have begun to look forward to the performance of the turbofan 10...”

 (End of this chapter)

Chapter end