Into Unscientific Chapter 560

  Chapter 560 You also have today, kid

In classrooms.

  Looking at Luo Shijun with a serious expression.

   Fifth Master Qian's complexion didn't change much, but a bad premonition faintly appeared in his heart.

  Luo Shijun was a personal disciple he brought with him when he was at Caltech, and he received a doctorate from Caltech as early as 1950.

   Even if you look at the aerodynamic field across the country.

  Luo Shijun can also be regarded as a top aerodynamic expert, and is even regarded by Qian Wushi as his successor.

   If not.

  Qian Fifth Division will not let Luo Shijun be the leader of the theory team,

To know.

  In the entire theoretical group, there are still one or two seniors with higher qualifications than Luo Shijun, such as Chai Zhi, the deputy group leader.

   Let Luo Shijun be the team leader, which is enough to show his ability.

   And right now, being able to get Luo Shijun to name the problematic power link is equivalent to a person having a problem in the field he is most proficient in.

  Think here.

   Fifth Division Qian immediately took the report from Luo Shijun and read it seriously.

   About five or six minutes passed.

   Only then did Fifth Division Qian put down the report thoughtfully.

  He first slowly looked around the scene, and finally put his gaze back on Luo Shijun, and asked his disciple:

   "Shi Jun, that is to say, in order to have a missile with the parameters we need, the body length must be between 90 and 100 centimeters?"

  Luo Shijun nodded heavily:

   "Yes, teacher."

  See this scenario.

   Xu Yun on the side didn't need an explanation from Fifth Master Qian, and immediately understood what Luo Shijun said about the power link.

I see

   Mentioned earlier.

  Due to the limitations of the airship's carrying capacity and stagnant height, the length of the missiles carried by the "Jade Sword Array" cannot exceed two meters.

  【No more than two meters】.

  This description seems to say that 0-2 meters is fine, but the actual interval value should be between 1.5-2 meters.

the reason is simple.

   Well known.

  Missiles usually consist of four parts. Or modules:

   Warhead,

   projectile structure,

powerplant,

   and the guidance system.

  The warhead is a special device for destroying the target, also called a warhead—the place where the combat charge is placed.

  The warheads of strategic missiles mostly use nuclear charges, and winged missiles usually use high-energy explosives.

  The missile body structure is the support structure that connects the various parts of the missile, that is, the shell and the link of the missile. The literal meaning is easy to understand.

  The power plant is the power source for missile flight, and is equipped with propellant and engine.

   For example, ballistic missiles generally use solid or liquid rocket motors, winged missiles usually use turbofans or turbojet engines, and so on.

  Not to mention the guidance system, Xu Yun designed an ultrwideband proximity fuze.

  These four components add up.

   is a relatively conventional missile.

  And these parts are not like Doraemon's different-dimensional pockets, no matter how heavy or bulky you are, they can be stuffed into palm-sized pockets.

in reality.

   Except that the projectile structure is regarded as the "shell".

  The remaining three modules all need to occupy a certain amount of internal space.

   Therefore, even if there is gravitational potential energy to provide kinetic energy, the length of the missile cannot be too short.

  Even a layman like Xu Yun, who doesn't know much about missiles, subconsciously imagines that the length of the missile will not be less than 1.5 meters.

   However, according to Luo Shijun's calculation results.

  In order to conform to the related equations deduced by Qian Wushi, the longest missile can only be one meter from the beginning to the end.

   This is the end of my life.

  A one-meter missile will require quite sophisticated design even in 2023.

   In the current period, to achieve this length, there are only two steps to take:

   Either change the material so that the new material meets the parameter requirements within an interval of 1.5 meters.

  or

   Come up with a whole new missile structure that can be shortened to one meter.

   After a while.

   Fifth Master Qian asked Luo Shijun:

   "Shi Jun, our existing missile program—whether it is the first generation or the fourth generation, under the premise of basic parameters"

   "Which scheme has the shortest missile body length?"

  Luo Shijun's memory is notoriously good in the missile team. At this time, there is no need to retrieve the data and the result is immediately reported:

   "Teacher, the shortest missile we have designed is 1.2 meters long, code-named Pandora, and it is the third-generation missile under planning."

   "Teacher, this is already the shortest missile we can design, and it is still a preset plan for 20 or 30 years. It is simply not capable of production now"

"1.2 meters."

  Fifth Master Qian frowned slightly when he heard this, and a dignified look appeared on his always amiable round face.

   But soon.

   This dignified look was replaced by another calm look.

   He took a deep breath, calmed down, and said to Luo Shijun:

   "Shi Jun, I've already understood the situation. It's really not easy in terms of difficulty, but you don't have to be too nervous."

   "After all, the superior department sent our missile team to the base to assist, isn't it because of various problems that may be encountered during the development of the Jade Sword missile?"

   "It is not an accident to develop an accident this time, and it is an accident if there is no accident. There is still a psychological expectation for this."

  Hearing Fifth Master Qian's last sentence, which seemed to be a bit of a tongue twister, Luo Shijun's face suddenly showed a hint of consternation.

right.

   They traveled thousands of miles from the capital to Jinyintan this time, didn't they come here to solve the problem of Zhuxian platform?

   Indeed.

   The problem of missile size is really not in their original preset scope.

   After all, a lot of high-altitude data can only be collected by meteorological Doppler radar, and no missile platform that stays in the stratosphere for a long time has been developed in China before.

  So among the many issues discussed in advance.

  Qian Wushi and others have preset many possible problems such as missile propeller, missile elevation angle, missile shaft speed, etc., but the body length has indeed been ignored.

   But that's no excuse to panic.

after all

   It is not that they have encountered more difficult situations than this.

  For example, the No. 1059 missile that was successfully launched last year.

three years ago.

  The rabbits officially began to imitate Maoxiong's P2 missile and named it 1059.

  In the whole process, the engine is the key in the missile imitation.

  But at that time, the rabbits didn't have many design drawings, and the core information was even blank.

  But under the leadership of Qian Wushi and others.

  The team of the Fifth Academy finally overcame many barriers such as materials, processes, equipment and propellants, and successfully mastered the key technology of the P2 missile liquid rocket engine.

   Then imitate near the end.

  Engine put into test requires a test bench, but there is no such equipment in China.

  So Xinmin, the chief engine designer at the time, keenly realized that if he did not test the vehicle in China, he would inevitably choke the neck of the independent development of domestic missiles.

   In the end he was without any physical assistance.

  Only relying on a small amount of textual information, a detailed test bench design task book was abruptly compiled.

   After nearly a year of engineering construction.

  The Rabbits' first large-scale liquid rocket engine test bench was finally accepted successfully.

   followed by a year after landing on the test bench.

  1059 The missile was launched successfully.

correct.

  1059 missile had a more famous name later.

   called

   Dongfeng No. 1.

  The entire development process of Dongfeng No. 1 was also full of various accidents, but the rabbits still persisted and resolved it smoothly?

  Think here.

  The astonishment and panic on Luo Shijun's face immediately subsided a lot.

  I saw him take a deep breath, and seriously said to Fifth Master Qian:

   "Director Qian, I understand, please give me instructions!"

  Fifth Master Qian patted him on the shoulder:

   "It's good to understand, there is no rush for instructions, go back to your seat first."

  Luo Shijun's expression was serious:

"yes!"

  After Luo Shijun returned to his seat.

   Fifth Master Qian also pushed Xu Yun's wheelchair back to the podium, and copied several structural parameters onto the blackboard:

  Missile body length:

  0.9-1.0 meters.

quality:

  13 kg.

  Center of mass position:

  0.5423.

  Slip angle:

  14.9°.

   Rudder deflection:

  2.0°-4.9°.

   Relative mass of the wings:

   After a few minutes.

   Fifth Master Qian stopped what he was doing and said to everyone:

   "Okay, comrades, here is basically the parameter structure calculated by everyone."

   A few more seconds passed.

   Fifth Master Qian drew a bar below the two parameters of body length and center of mass position, and continued:

   "The easier problems should be dealt with before the harder ones, so among these two problems, let's solve the centroid shift first."

   "We take the Pandora missile as a sample, and the length of the missile is reduced to one meter, so it means that its center of mass must be compressed."

   "We still list Jx, Jy, and Jz, which are the moments of inertia of the missile relative to each axis of the missile coordinate system."

   "ωx, ωy, and ωz are the components of the rotational angular velocity ω of the projectile coordinate system relative to the ground coordinate system on each axis of the projectile coordinate system."

   "Then there is."

  I saw Fifth Master Qian quickly continued to write down an equation on the blackboard:

  Jxdωx/dt+(JzJy)ωzωy=Mx

  Jydωy/dt+(JxJz)ωxωz=My

  Jzdωz/dt+(JyJx)ωyωx=Mz (Note: Let's explain again, don't say that I use formula hydrology, 7 letters are equal to one Chinese character, and the replacement of this row of letters into Chinese characters is less than half of what I noted.)

   It is not difficult to see from the expression.

   This is a kinetic equation for a missile rotating around its center of mass.

  Then Fifth Master Qian added the aerodynamic coefficients cx, cy, and cz to them.

   Write here.

   Fifth Master Qian couldn't help but stop what he was doing.

   Facing a middle-aged man with straight brows and a fuller and rounder face than others, he said:

   "Huaijin, let me tell you about the following thinking."

  There were more than 20 people on the scene including the liaison officers, and there was only one person with Huai Jin in his name.

  This person is the chief designer of the later Hongqi No. 2, Mr. Chen Huaijin—still the youth version pro.

   Hearing what Qian Wushi said.

  Chen Huaijin immediately stood up from the seat, and accidentally brought the stool down due to excessive movements.

   Fortunately, Chai Zhi, who was on the side, had quick eyesight and quick hands, and supported the stool before it fell to the ground.

  Chen Huaijin didn't seem to notice her movements, her eyes were fixed on the blackboard.

   After a while.

  Chen Huaijin organized the language and said:

   "Director Qian, I think it is possible to add a moment with a negative sign to the right side of the equation?"

   "In this way, the error brought about by the center of mass in mathematics can be eliminated."

   "This moment can technically be achieved by rolling the missile body, that is, using a tail with a little deflection, so that the missile rotates around the axis at a low speed during flight."

   "In a certain period, the specific period value must be calculated. In short, the problem of moving the center of mass forward can be solved by turning one circle within this period."

   "At the same time, the total aerodynamic force is also a vector. When it does not pass through the center of mass, it will also generate a moment that makes the missile rotate. When the sum of these two moments is not zero."

  Looking at Chen Huaijin who was talking eloquently.

  Xu Yun experienced for the first time what Qiao Caihong felt when he was listening to physics class.

  So this is how it feels to grow a brain

  You also have Today.jpg.

no way.

   Mentioned earlier.

  You asked Xu Yun to calculate some things about fluid mechanics. After all, Xu Yun has taken this course, and mathematical calculations are also common.

  But when it comes to the research and development of missile body, he is a real newcomer.

  He can understand or understand every word, but he can only express the meaning of the word together with a question mark on his face

certainly.

  Although I don't understand the specific principle.

  But Xu Yun still has the ability to read words and expressions.

  From the frequent nodding of Fifth Master Qian, it is not difficult to see that what Chen Huaijin said should be correct, at least in general.

   Actually what Xu Yun didn't know was.

  The advanced version of the principle mentioned by Chen Huaijin is actually the center-of-mass principle of the air steering of the Hongqi 17 missile in later generations.

  The whole principle can actually be described in one sentence:

  The center of mass is before the center of indentation.

  The projectile is stable;

  The center of mass is after the center of indentation.

  The projectile is unstable.

  However, if the unstable state of the projectile is well controlled, the center of mass can regularly jump repeatedly before and after pressing the center

   Then some bugs can be stuck.

   This operation is somewhat similar to the Supreme Lord of the Rings in "Lord of the Rings".

  When Frodo puts it on, the Ringwraiths will find him, and when he unties it, he will lose the target, so you can wear it from time to time to attract monsters.

   Then about ten minutes passed.

  Chen Huaijin just finished talking about her thoughts.

  Fifth Master Qian nodded in satisfaction, and affirmed:

   "Comrade Huai Jin's idea is very subtle, but on the basis of Comrade Huai Jin, I would like to add a little bit."

   "That is, we can actually apply a deflector on the tail of the missile, and generate another moment through deflection and friction."

   "This moment is perpendicular to the central axis where the center of mass is located, and parallel to the airflow ring ratio tangent of the jet port. In addition"

   Hearing Qian Wushi's words.

  Chen Huaijin, who was standing there, was taken aback for a moment.

   After a while.

  He suddenly slapped himself on the head heavily, with a cry:

   "Yes!"

   "If a deflector is used to increase a moment, then no matter whether the center of mass moves forward or backward, the heat energy that needs to be consumed will be much smaller."

   "In this way, the margin of the missile can be freed up to place other equipment or propellant!"

  Xu Yun still looks OvO:

   "Ah yes yes yes."

  Afterwards, Fifth Master Qian directly wrote Chen Huaijin's plan on the blackboard, and there was another large line of formulas densely packed.

   Here we go.

   The difficulty of the center of mass has been answered.

   Solved the centroid problem.

  The rest is the most intuitive link:

  How to reduce the length of the missile?

   After all, the center of mass considers the displacement of the center of pressure after the missile is reduced to one meter, which belongs to the level of subsequent optimization.

   To handle this optimization, the length of the missile must be solved first.

  The reason why Fifth Master Qian solved the problem of the center of mass first is to take into account that the mobs should be cleared first so as to focus on the big boss, and the second reason is.

  Use a relatively simple question to increase the confidence of everyone.

   Now the mobs have been cleared, and the rest is the master.

  Think here.

   Fifth Division Qian could not help turning his head to look at the deputy team leader Chai Zhi, and asked him:

   "Old Chai, what do you think?"

  Chai Zhi's age was second only to Fifth Master Qian on the scene, and he was also an extremely experienced old comrade.

  After hearing Fifth Master Qian's questioning.

  Chai Zhi quickly opened the notebook in front of him and said:

   "Director Qian, first of all we need to make one thing clear."

   "That is, if the missile wants to reduce its body length to one meter, it is obviously necessary to compress the internal structure of the missile."

   "According to my simple estimation, the length of the warhead warhead can be optimized by about 10 centimeters when it is completely smooth."

   "After all, the U2 reconnaissance aircraft is different from other aircraft. Its body shell is very thin-this is one of the few data released by Mao Xiong."

   "So I think we can appropriately reduce the capacity of the warhead to reduce the length of some missiles."

   Chai Zhi finished speaking.

  Some people were silent at the scene.

   Some frowned.

   Some people nodded.

   Among those who nodded, Xu Yun was surprisingly included.

   Mentioned earlier.

  The U2 reconnaissance aircraft is a model that is completely used for reconnaissance, so that it can be said to have been castrated in many attributes.

   Such as the detection radar mentioned earlier.

   Another example is that its landing needs to be guided by a tractor. When it lands, one side of the wing will inevitably wear out when it touches the ground.

   Another example.

  U2's body is extremely thin.

   Moreover, in order to dissipate heat from the engine, there is a gap tens of centimeters wide behind the body.

   It is not an exaggeration to say.

  In the area behind the rear of U2, you can cut a gap with a kitchen knife ten times—this is a true thing that has been tested.

   And because of this.

   The amount of charge on the warhead of the sniper U2 missile can actually be reduced.

  Through the optimization of the warhead, the length of some missiles can be reduced.

  For example, in some military forums of later generations, many people have discussed a problem:

  How much can the warhead of the Sam-2 missile be reduced to successfully blow up U2?

  Although this question is often skewed in the end to whether it hits the fuel tank or the head area, it is similar to whether a 155 howitzer hits a tank from the side or the front.

  But a more recognized value is

  5 kg.

   That's right.

  Sam 2 with 135 kg warhead charges, in fact, only 5 kg warhead explosives can blow up U2.

  A Sam 2 is still the case.

   Not to mention that there are four missiles on the Zhuxian Sword Formation.

  Under the guidance effect of the ultrwideband proximity fuze, Xu Yun estimated that the warhead only needs 3 kilograms of explosives.

  Counting the shell of the warhead, the mass of the entire warhead should be reduced to 4 kg.

  The line of sight returns to reality.

  After Chai Zhi finished speaking.

  Fifth Master Qian did not show a clear expression on his face, but gestured to Chai Zhi:

   "Old Chai, go ahead."

  Chai Zhi nodded. Having cooperated with Fifth Master Qian for many years, he knew that Fifth Master Qian had adopted his idea, so he continued:

   "In addition to the warhead, there are only the proximity fuze, the engine and the propellant part."

   "I saw the diagram of the proximity fuze at Dean Sun Junren's place in the morning, and the total amount is about one finger (thumb down, **** up straight distance), basically there is not much room for optimization."

   "As for the power composition of the engine, not to mention, the engine of the micro missile is so big, we can't reduce it in terms of size or accuracy."

   "So theoretically another place that can be optimized is the combustion chamber where the engine stores propellant."

   This time.

   There are obviously many more people who agree with it.

  It was mentioned above.

  The rabbits didn't master the rocket engine test bench until last August.

  So let's not talk about the theory of the front end of the engine.

   Just the upper limit of equipment accuracy, the rabbits' engine development is locked to death.

in this case.

   Winged missiles use rocket motors or air-breathing motors.

   Therefore, it is impractical to optimize the engine structure—even if someone comes up with a better solution.

  After all, the production mold determines the accuracy, unless you can come up with another set of more precise equipment.

  Therefore, the only modules left in front of Qian Wushi and others that can theoretically be optimized are—

  The volume of the combustion chamber.

   Then Chai Zhi paused, and continued:

   "According to our original design, the length of the combustion chamber of the 'Pandora' missile is 39 centimeters, occupying 1/3 of the length of the missile body."

   "This length is even longer than the warhead of the missile. If it can be reduced by more than ten centimeters, then the development of a one-meter missile may be realized."

   Fifth Master Qian also nodded and looked at the crowd:

   "Comrades, does anyone have any different opinions on what Comrade Chai Zhi said?"

  Everyone at the scene shook their heads in unison.

"very good."

  Seeing this, Fifth Master Qian decisively issued another instruction:

   "Since everyone has no problem with this theoretical direction, let's discuss how to reduce the warhead."

   "Now is the time for free discussion. Anyone who has an idea can express their opinion. Is there any comrade who can start?"

   Fifth Division Qian just finished speaking.

  A boy who had not spoken all this time raised his hand.

  This person, Xu Yun, met his name when he was introduced by the Fifth Division Qian. The deity is Mr. Shen Zhongfang, the commander-in-chief of China's third-generation medium-to-high-altitude and long-range air defense missile models.

   According to some resumes published by later generations.

  Mr. Shen is a radical in research and development. He often proposes some risky but profitable ideas, which is quite individual.

  For example [an engineer said with a smile, I hope that the 59 modification can be sent to heaven in the future] The source of all evil comes from the mouth of Mr. Shen.

   But at that time, he hadn't passed the declassification period, so the report just used "a certain engineer" instead.

  Then Fifth Master Qian made a gesture of invitation to him:

   "Zhongfang, please tell me."

  Seeing this, Shen Zhongfang also stood up from her seat, looking very energetic, and said:

   "Director Qian, I have a bold idea."

   "Since the warhead is reduced, the dose of propellant must also be reduced, right?"

   "So can we replace a more efficient propellant so that it can produce the same energy as the original in a smaller volume?"

   "For example, some kind of special propellant that is being developed."

   "Special propellant?"

   Fifth Master Qian repeated the word twice, and immediately his expression changed.

  As the current head of the missile team, he soon realized what Shen Zhongfang said.

   Well known.

   Tsiolkovsky deduced the ideal velocity formula for a single-stage rocket in 1903:

  V=ω×Ln(Mo/Mk).

   This is also known as the Tsiolkovsky formula.

   where ω is the jet velocity of the engine.

  Ln is a logarithmic expression.

   represents the logarithm with the natural logarithm e as the base.

  Ln(Mo/Mk) is expressed as the logarithm of Mo/Mk with e as the base.

  What about Mo and Mk?

   are the initial mass of the rocket and the mass when the engine is turned off, that is, when the propellant is exhausted.

  So Mo/Mk is called the mass ratio of the rocket. (This formula is very important, it is recommended to insert an eye)

  So after the Tsiolkovsky formula came out.

  Rocket propellant also began to develop.

   In terms of physical form.

  Propellants used in rocket motors come in two forms:

   One is a liquid substance.

  The other is a solid substance.

   An engine in which both the combustion agent and the oxidant are in liquid form is called a liquid fuel engine, or a liquid rocket engine.

  If both are in a solid state, they are called solid fuel rocket motors or solid rocket motors.

  In this period.

  Liquid rocket propellants are considered the mainstream of technology, and the status of solid rocket motors is far from that of later generations.

  Among them, the first generation of liquid rocket propellants used liquid oxygen plus gasoline, which is considered a relatively primitive method.

  The second generation is liquid oxygen plus alcohol. This propellant has continued until now:

Its principle is to cool the thrust chamber by means of liquid film cooling and regenerative cooling, and use the high-temperature airflow generated by the decomposition of hydrogen peroxide catalyzed by sodium permanganate to drive the turbo pump for pumping pressurized delivery of propellant .

  The thrust of this mode can reach 2.5 tons, which is enough to launch many missiles.

   But with the development of science, the propellant is constantly being updated.

  For example, a brand-new propellant has appeared in the world, called

   Mixed hydrazine 50.

  Its alias Aerozine50 is a 50/50 mixture of hydrazine and unsymmetrical dimethylhydrazine UDMH, which was developed by General Aviation Jet Company across the sea two or three years ago.

  Its propulsion force is indeed much higher than that of the second-generation liquid. In the words of later generations, it is the "son of the version".

  The special propellant mentioned by Shen Zhongfang is exactly this raw material.

but

  This kind of extremely toxic substance has a leakage probability of more than 60% in the current domestic pressure vessels, and it is very unstable.

  Due to technical barriers, domestic research on it has just started—about February last year, China only mastered the structural formula of this mixture.

  From the domestic research and development to the present, the success rate of the sample rocket successfully launching is less than 30%.

   Therefore, this is not a good choice whether it is from the perspective of security or stability.

  However, the problem is that besides replacing the propellant, the Fifth Qian Division seems to be unable to find any other usable method.

   Do you really want to use this?

   And just as Qian Wushi was hesitating.

  From the corner of his eye, he suddenly caught a glimpse of Xu Yun beside him.

at the same time.

  The words of the chief appeared in his mind again:

   "Just use Han Li as a donkey"

  Think here.

   Fifth Division Qian could not help coughing lightly, turned to look at Xu Yun, and asked him:

   "Comrade Han Li, what do you think?"

"Ah I?"

  Xu Yun was watching and eating melons silently, but he was a little surprised when Fifth Master Qian asked him so abruptly.

   After regaining consciousness.

  He subconsciously prepared to shake his head.

   After all, he really doesn't know anything about missile design. It is obviously impossible for you to ask him to say any optimization theory.

  However, just as the words were about to come out.

  In Xu Yun's mind, inexplicably, the waverider technique mentioned by Qian Wushi flashed across.

   Immediately after.

  A news report he had seen in reality came to his mind.

  In addition, Qian Wushi said it before.

  Xu Yun only needs to be Party A, and he can make any unconstrained request.

  So Xu Yun was silent for a moment, and said to Fifth Master Qian:

   "Director Qian, I do have an idea, but please don't hit me if you say it."

Note:

  The last few days at the end of the month, please ask for a monthly pass. This month is really desperate for changes.

  The goal at the beginning of the month should be completed according to the current situation, but there are still three days to update, so the flag will not be set. The specific data will be reported on the 31st.

  (end of this chapter)

Chapter end