Chapter 433: Bearings are a big problem
Noine looked at the computer screen that clearly stated how to operate to increase the range and how to operate the rocket to anti-ship, and for a moment he was a little confused. How to evaluate.
In fact, let alone him, even Zhang Hongyin was a little confused when he saw this plan for the first time.
The launch dynamics of rockets, especially rockets with a large aspect ratio, is an extremely complex subject in itself, and a long-range ballistic weapon with a range of more than 300 kilometers like the Guardian 2 has to undergo There are multiple temperature layers with completely different environmental conditions. In the final analysis, the design idea has completely broken away from the scope of general artillery weapons.
Allowing customers to change the missile body design on their own can easily make the ballistic computer with poor performance even worse.
Especially extending the range of ballistic weapons cannot be solved by adding more fuel.
If you mess with the upper structure of the rocket, the stability will be deteriorated and it will fly randomly and completely without accuracy after launch, or it will disintegrate before hitting the target.
At that time, the Iraqis put two Scuds together and assembled them into a ballistic missile with a longer range. However, almost none of them landed normally after being launched. In the end, they were all included in the Patriots' interception "results." "in.
But Rui Xiaoting said very confidently that he had fully considered the issue of launch dynamics. The new missile body after replacing the seeker can share the launch table data with the prototype missile, and the terminal stage is also OK. Relying on active radar guidance to adjust the flight attitude, the accuracy of hitting a frigate dozens of meters long can still be guaranteed.
As for the extended-range version, there are no changes to the missile body itself at all. Instead, the maximum range is extended by modifying the parameters of the solid rocket motor.
In short, Rui Xiaoting quickly convinced Zhang Hongyin, who was worried, with professional and accurate calculation results.
Of course, the customer does not understand the technology, and the detailed design data is a commercial secret and cannot be fully disclosed, so we can only rely on test firings to speak for itself.
But this is not over yet.
The PPT on the computer screen quickly turned to the next page.
“In addition to the three existing ammunition modes, we also plan to produce supporting drones for the Guardian 2 rocket system, which can be loaded directly into the launch box and launched through booster rockets and blocking nets. Recovery, under certain necessary circumstances, can carry out artillery reconnaissance and meteorological observation missions, as well as co-launched, larger-caliber ballistic missiles..."
If Rui Xiaoting learned anything else besides the usage of TORCH Multiphysics at Beijing Hang University, it must be Chang Haonan's cake painting skills.
Be it the drones or ballistic missiles I just mentioned, it would be too much to say it was a plan. In fact, it was just the content of the brainstorming session between him and Zhang Hongyin on the way to the shooting range.
After all, these days, the entire Chinese army has few serious drones, and the domestic aviation field is still close to blank in this regard.
This is not a problem that those in the weapons industry can solve.
However, Noine on the opposite side obviously didn’t know this. He thought that these were very mature technical solutions like the previous parts, so he asked for a lot of details.
Fortunately, half an hour was not long, and before Rui Xiaoting could no longer continue editing, it was time to conduct a launch test.
On the monitor not far away, the 6*6 launch vehicle just now was speeding on a dirt road. After several turns, it stopped at the preset launch position, and then slowly lowered its support. shelf.
“Because the fire control computer has been upgraded, I no longer need to wait until entering the firing position to calibrate the shooting elements. I have already preset the coordinate data of the target in the preparation area, and now I only need to adjust Just take it out, which greatly speeds up the reaction speed from entering the position to launching..."
Zhang Hongyin explained beside him.
As soon as he finished speaking, with a burst of dust flying, the first rocket broke through the sealing sheet in front of the directional tube and shot out like an arrow off the string.
Then came the second and third rounds...
“Compared with the previous generation product, we have modified the design of the frame, hydraulic mechanism and directional tube, and the firing interval between each two rounds has been shortened to 2 Within seconds, the firepower density is also more guaranteed."
In the time it took to speak, all six rockets were fired, the support frame of the launch vehicle was raised, and then the launch position was withdrawn as quickly as possible. .
The whole process probably lasted less than four minutes.
“The shorter the time from entering the position to withdrawing from the position, which means the lower the danger of the launching unit. Compared with the 10-15 minutes transfer time of most artillery units, our survivability It can be increased by about four times. "Of course, with the range of the Guardian 2, there are not many weapons that can threaten it..."
By this time, the way Noine looked at the screen was different from the beginning.
Although there was no movement in the target area, he had already made up his mind that as long as the final accuracy was not too outrageous, he would definitely place this order.
After the long wait.
In another camera, six successive fires covered the entire target point with a white circle...
"Bang!"
Noine smashed the table in excitement:
"You two, I want to go and take a look at your factory."
......
Chang Haonan, who was far away in the capital, naturally didn't know that Rui Xiaoting had already played Guardian 2 to a great extent after getting his software.
After sending the design of the Air Police 200 to the Fucheng Wind Tunnel, he naturally returned his main focus to the aeroengine.
Although the compressor and turbine experimental devices have not yet been put into use, this does not mean that related research cannot be carried out at all.
Since the 1980s, Chang Haonan has obtained a vast amount of aviation engine usage data nationwide since the 1980s from the Committee of Science and Industry.
Especially breakdown and accident data.
From the feedback of the use of turbojet 7/13, Spey MK202 and various other models, including civilian models, the main pain points are other than the fluid dynamics design that has always attracted more attention. There are also many problems at the mechanical manufacturing and mechanical design levels.
For example, he found that among the in-flight parking accidents caused by all engine components, only the main shaft high-pressure rotor front fulcrum (three-point) bearing and the LPT shaft fulcrum (four-point) bearing accounted for nearly 40%, which affected flight safety. The main problem.
In aviation engine maintenance data, replacement records of parts at these two locations are often seen.
Take the turbojet 14 that has just been put into use as an example. In theory, the three-point ball bearing needs to be replaced 3-4 times during the entire life cycle. However, for the SPEI MK202, which has a longer overall life, the number of replacements is even higher. It will take up to 6-7 times, which adds a lot of workload to the ground staff and seriously affects the aircraft readiness rate.
The fundamental reason is that during the take-off, climb, cruise, landing and other stages of the aircraft flight cycle, the rotor system load, speed and other operating parameters continuously change with the engine flight envelope. Typical service conditions are high speed, Heavy load, high temperature, etc. During flight, aircraft engines are affected by short-term transient conditions such as surge and rotor imbalance. As a result, the two bearings involved in high-pressure rotor support often have to withstand extreme operations such as speed changes, load changes, over-rotation, oil cuts, and oil starvation. Under the test of environmental conditions, early failures and benign contact fatigue failures originating from subsurface layers often occur.
As for the solution...
Considering that even engines like the CFM56 are plagued by bearing failures, simply replacing them with better materials is definitely not enough.
It is also necessary to carry out analysis of the three-point contact state of the main load-bearing area, the hoop stress of the inner ring and cage performance under high-speed operating conditions, the lubrication state, and the temperature field analysis for the typical service conditions of aeroengines. The relationship between condition changes and structural parameters and bearing performance is realized to achieve parameter optimization of bearings and surface fatigue and damage resistance design.
And this happens to be the part that Chang Haonan plans to focus on next.
Because this technology is also crucial for the heavy-duty die forging press project that may be launched soon.
"Let's start with you first..."
Chang Haonan put down the statistical form he had just prepared, picked up the receiver of the red landline phone from the table, and dialed Ding Gaoheng.
(End of this chapter)