Chapter 844: Chapter 445: Main Design Completion, Review Group Arrives_1
After Zhao Yi presented the design idea, the R&D team began to justify the project in terms of materials and design.
The design aspect was still managed by Sun Lei and Zhao Yi, with the involvement of Zhou Qing, who demonstrated the meaning of participation. He simply voiced an idea, which Zhao Yi expanded into a feasible proposal. Zhou Qing didn’t understand construction or design issues; most of the time, his role was limited to serving tea and water.
However, Zhao Yi still let Zhou Qing participate, since it was Zhou Qing who provided the initial idea.
In R&D, ideas or creativity are crucial; without them, there is nothing. Zhou Qing only provided an idea, but it was this idea that led to the design.
This is the contribution to R&D.
Li Rongmao and Zhang Hong Tao were responsible for the materials aspect, needing to work together to determine which materials met the requirements and to list in detail the performance and parameter indicators of these materials. They were not to list just one type but many, to create an analysis report of advantages and disadvantages.
The R&D team spent the next three days doing this work.
Three days were enough to finalize the design.
Ultimately, they put forward a solution that met both design and material requirements, finalizing the design for the relief valve.
And then, the only remaining issue with Sun Lei’s design proposal was—
The pipeline problem!
The compressor is located in the middle of the turbofan engine, positioned between the combustion chamber and the turbine group, with the pipeline routed parallel to the exhaust outlet across half the engine’s length.
This distance was simply too long.
As the engine’s inner skin needed to withstand very high temperatures and pressure, constructed of at least titanium alloy, adding several internal pipelines would significantly increase the weight. The power provided by the piston was very limited; even while operating, if it reached five percent of the main exhaust jet’s power, it was already the theoretical maximum.
This power was actually not insignificant, because when the fighter jet decelerated, it would greatly reduce fuel supply. With the relief valve providing auxiliary power, fuel supply could be further reduced.
However, compared to the added weight of the engine, designing pipelines parallel to the exhaust jet would surely be a loss.
Ultimately, it was still a design issue, but pipelines are not like the relief valve, which can use a clever design to compensate for other problems. The shortest distance between two points is a straight line, and it’s very difficult to achieve any significant effect with more elaborate designs in terms of length.
Of course, there were still solutions.
Yuan Haitao offered an idea. He believed that the exhaust could be placed in the secondary duct. A turbofan engine has more than one duct; the primary duct serves as the source of the engine’s power, with all its components catering to this main duct, while the secondary duct surrounds the primary duct. The primary reason for the secondary duct’s design was that the front fan took up too much space, while the central compressor occupied too little.
When the fighter jet flew at high speeds, the high-velocity air couldn’t all pass through the main duct, turning the engine itself into a significant resistance. Hence, secondary and even tertiary ducts were designed.
As wind intensity increased to a certain level, the vents of the secondary ducts would open to let the air pass directly through them, and similarly, tertiary duct vents would open when the wind intensity grew even higher.
If the relief valve’s exhaust was placed inside the secondary duct, the high-pressure air could be discharged directly into it, flowing along the duct and out the vent.
This idea was immediately rejected by Zhao Yi and Sun Lei because releasing high-pressure air into the secondary duct would not augment thrust, which defeated the purpose of the previous design. ƒгeewёbnovel.com
Therefore, the air relief valve’s exhaust could only be positioned inside the primary channel, preferably where the high-pressure air could also serve another purpose, such as entering the combustion chamber to promote fuel burning.
"Putting it into the combustion chamber is impossible,"
Sun Lei immediately shook his head, "The temperature in there is too high. The heat could backflow through the exhaust into the pipeline, easily causing damage."
Zhao Yi nodded, "Let’s rule out the combustion chamber. We still have to place the exhaust vent at the edge of the main jet," fɾeewebnoveℓ.co๓
"That could work,"
he pondered for a moment and then said, "We can redesign around the perimeter of the primary duct and the exterior of the secondary duct to bring the edge of the combustion chamber and the jet nozzle closer, reducing potential weight increase."
"Let’s give it a try~"
With the R&D direction set by Zhao Yi, no one else had any objections; they were complete novices when it came to designing the engine’s skin. Not one had undertaken similar design work before.
Everything depended on Zhao Yi alone, but for him, the difficulty of this design wasn’t prohibitive. Others might need to consider various factors while designing, but with enough conditions met, he could effortlessly achieve the desired structural design. In just a day and a half, he came up with a design plan.
This plan involved shaping the outer layer of the compressor into an arc. Since the combustors on either side were small, the compressor semi-encased the combustion chamber, allowing the relief valve’s exhaust pipes to directly cross over the combustion chamber and through the thick outer layer of the turbine group to reach near the edge of the jet nozzle.
Although it was still a straight traversal, the length of the pipeline was significantly reduced to just a quarter of the original; it could be incorporated within the inner skin without needing an extra layer of material.