Chapter 190 Persian Tomcat
“DSI air intake?”
Although the related concept has been proposed very early, it was obviously not very common in 1997, so Sun Huizhong After thinking for a while, I searched for relevant knowledge in my mind:
"I remember...a few years ago, the United States built some advanced compact air intake system, and it seems that it was studied. This thing?”
“Yes.”
Chang Haonan nodded. In an era when information was not developed, he was really impressed that the other party knew this:
"Actually, I already had the central idea of the DSI air inlet in my previous design. It has been applied.”
While speaking, he had already drawn a cross-sectional diagram of a DSI inlet and a partition inlet on the blackboard:
“Above the J-7F. , I used the nose radome as a cone-shaped precursor instead of a complex partition to process the incoming flow once to prevent low-energy flow from entering the air intake, which greatly improved the air intake efficiency.”
“But in fact, the standard semi-conical shape is not very precise in controlling the flow field, so a more complex fan-shaped lip design is still needed to improve the ability to exclude the boundary layer, which will bring great resistance. , on the other hand, it will increase the volume of the air intake and add back the weight saved by eliminating the partition.”
Hearing this, another engineer next to him seemed to think of something:
“I have indeed seen a photo of the F16. Although it is a bit blurry and it is black and white, the air intake is indeed the same as the one on the blackboard. Almost, the appearance is quite exaggerated, a bit... a bit like what you said before."
Sun Huizhong is obviously thinking more deeply:
"So, this DSI air intake. The key to the design lies in the... shape of the bulge near the lip?"
The following content was completely beyond the scope of Chang Haonan's painting skills, so he simply did not continue with the pointless attempt. .
Fortunately, we are all professionals, and we can explain everything with words alone:
"Yes, the bulging compression surface of the DSI air intake is designed based on the waverider principle. Its benchmark The shape is still a conical surface, but several tracking points need to be selected from the front edge line. In the flow field, start tracking from these tracking points to the downstream of the flow field. The flow surface formed by these tracked streamlines is the bulge compression surface. . ”
“Although this process is not difficult to say, the numerical calculations involved are quite complicated. I also need to sort out my ideas, so I am not in a hurry. I will first give the overall design according to my previous plan. Let’s work it out.”
In fact, Chang Haonan’s idea is similar to his previous idea for Turbofan 9, which is to research certain key new technologies in advance for subsequent key models.
Last time it was for the Turbofan 10, but this time, it is undoubtedly for the J-10.
Since in this time and space, the J-8C has successfully completed the design and finalization and been delivered to the troops for trial, so for third-generation aircraft, especially single-engine medium-sized third-generation aircraft like the J-10, it has been possible to completely give up the pursuit of speeds above Mach 2.0. , and instead focus on optimizing overall performance at medium and low speeds.
Now that the No. 01 prototype of the J-10 has reached the final assembly process, it is naturally impossible to reinvent the wheel, but the new DSI air inlet design can still be used on subsequent full-state prototypes.
As long as his efficiency is high enough.
After all, the shape of the air intake of the J-10 itself has undergone a major change.
On the full-size model in 1991, an air intake similar to that of the F16 was used.
When it came to the prototype stage, it was replaced with a two-dimensional adjustable inclined plate inlet that focused more on high-speed performance.
The previous Xiaolong only really used the DSI air intake design from the No. 04 prototype.
In addition, the design of prototype No. 01 will not be wasted.
It can definitely be exported.
China does not need the high-speed capabilities of the J-10, but it does not mean that other countries do not need it either.
Most countries have only one type of main fighter aircraft, and this model is needed to cover everything. Therefore, an old design with relatively good air intake efficiency in the full airspeed range would be more suitable.
... Just when Chang Haonan was taking advantage of the few time he had a year ago to conduct research on new aircraft and new designs in Chengdu, the 410 Factory in Shengjing ushered in a group of people who had been waiting for a long time for the Chinese military industry. Unseen guests——
A delegation from Persia.
The leader was Brigadier General Mark Welsh, the chief of staff of the Persian Air Force.
Among the people responsible for reception, Zhong Shihong, who is responsible for technical work, is naturally indispensable.
In fact, during the Xiangzhou Air Show in early November last year, the Persians had already shown a strong interest in several models. The subsequent development did not exceed the expectations of the aviation technology group. They quickly We received a request from the other party for cooperation in arms sales.
But no one expected that Persia first expressed interest in neither the J-8C nor the J-7F, but the Turbojet 14.
So under the leadership of Zhong Shihong, the Persian delegation spent about a day visiting the final assembly workshop and part of the production workshop of the 410 factory——
Again, Hangfa If you can figure out things just by looking at them, then China wouldn’t have been able to come up with a stable turbofan 10 until 2010 in the previous life...
"Brigadier General Welsh, I wonder what kind of fighter jet you plan to use our aviation engine to adapt to?"
Zhong Shihong almost subconsciously thought that the other party was going to buy an engine during this trip.
As a factory owner, he does not need to think about "whether it can be sold". That is the task of the Science and Technology Commission and the Aviation Technology Group.
Besides, although the Turbojet 14 is a top-notch aviation engine for China, if you really want to compare it on a global scale, it is actually not a particularly extraordinary black technology. If someone really buys it, there is nothing wrong with it. For sale.
The Chinese military industry in this era is not yet at the level of being picky about its customers.
But he was obviously wrong.
After hearing the question through the translator, Welsh shook his head decisively:
“No, Mr. Zhong, we are not here to buy your engine. After all, to be honest, with Considering the current level of the aviation industry in Persia, it may be difficult to fully produce fighter jets.”
“We want to entrust you with the overhaul of a batch of turbofan engines.”
When he first heard this answer, Zhong Shihong thought it was a mistake in the translation.
But he soon realized what the other party was talking about:
“Are you referring to the TF30 engines on those F14s in your army?”
“That’s right.”
Welsh turned around, looked at several turbojet 14 engines being assembled in the factory and said:
“You should know that the combination of TF30 and F14 does not perform satisfactorily in terms of reliability. , even though our pilots are very careful when driving, engine surge and other failures often occur.”
"Over the years, the spare parts previously purchased have been exhausted. After all, the number of parts obtained through special channels is limited, and the quality and quantity are unstable. The F14 is our main model, so we thought of seeking technical help."
(End of this chapter)