PDLP Chapter 679 Trying to bait me? Dream on!
Chapter 679 Trying to bait me? Dream on!
"These are the two core parameters that I think are important!"
“Therefore,” Jiang Xia concluded, “I suggest using θ = 10° as the design reference angle for preliminary calculations. This will effectively suppress eddy separation, reduce ξd to around 0.15, and avoid the cone being too long. Then, calculate the required cone length L based on the specific pipe dimensions (D1, D2).
Jiang Xia paused briefly after a satisfying typing session, a surge of pleasure—a feeling of "spoiler alert"—rushing straight to the top of his head:
"In terms of structural design, the cone can be divided into 3-5 segments, with very subtle adjustments to the cone angle of each segment, such as gradually changing from 11° at the inlet to 9° at the outlet, forming a smooth streamlined transition. This further optimizes ξc, bringing it close to the lower limit of 0.05. In this way, the multi-segment micro-element model has a clear physical meaning and design basis."
perfect!
Jiang Xia stopped typing and a knowing smile appeared on her face.
Secretary Liu, who was standing by, assumed he was checking the screen for typos, unaware that Jiang Xia was inwardly laughing hysterically: "Hahaha, teachers, look at these standard answers, aren't you surprised? Aren't you taken aback?"
Hehehe, I'm not going to tell you that this golden θ angle was something you guys figured out after scratching your heads for ages!
In his moment of triumph, another brilliant idea struck him: That's it! There's also the Moody Chart! This is a treasure trove of information! It specifically describes the intricate and complex relationship between Darcy friction factor, Reynolds number, and pipe roughness.
It can handle not only round pipes, but also oddly shaped pipes! It's practically a "universal diagram" for fluid mechanics and engineering!
Since its creation in 1944, this diagram has been kept under tighter control by certain people than a family secret recipe.
Jiang Xia slapped his thigh: "Great idea! Let's take this opportunity and give it away as a gift!"
With this diagram, along with the 'steam flow calculation table' that these experienced workers have developed over half a lifetime, not to mention designing a flow guide cone, any job involving pipelines will save a lot of brain cells!
Jiangxia typed away on the keyboard, his mood beaming. His secretary, Xiao Liu, watched with envy and a racing heart; his brother's typing speed was truly impressive!
Old Wang was like an ant on a hot pan, so anxious that he scratched his head and cheeks.
His mind was still filled with that strange ship! With his heart set on the navy, he couldn't wait to grab Jiang Xia's tuft of hair and ask him exactly what a "hydrofoil" was!
Unfortunately, this thought could only flutter wildly in his mind. If he dared to put it into action, the consequences could be severe…
Actually, it's partly Old Wang's fault for not gathering enough information, or perhaps the Navy was too embarrassed to say it...
After all, it's quite embarrassing to talk about this.
A group of water dragons couldn't get the small boat moving! Liu Huaqing and the others were so anxious that they were pulling their hair out of the small boat's hair around the engine, which was much smaller than a diesel engine.
Finally, having no other choice, they had to use a cable to drag the "old man" back.
As a result, when it was being towed, the dilapidated boat was still restless, trying to jump onto the hull of the Anshan. Its posture was just like a big yellow dog that had been holding back its desires and suddenly saw its favorite "Ahua" and couldn't wait to "take over" immediately!
This "floating disco" style of behavior actually made a group of naval officers and soldiers laugh.
The captain of the Anshan was so angry that he wanted to fire a 130mm main gun at it and send it to the seabed to "refine its restless heart".
That's a story for later, so let's leave it at that for now. Surprises always need to come at the right time to really get our blood pumping. We must still have faith in Uncle Kim's unwavering character...
……
At this moment, Jiang Xia had already finished drawing the two pictures using the simple interface of the text message. Although limited by the graphic display, the originally smooth curves could only be made up with "..." and "----", which made it look a bit like abstract art.
Well, it's roughly correct; as long as you can understand the meaning, that's fine! Accurate data is the most important thing! If it really doesn't work, I'll draw a proper diagram later...
Jiang Xia withdrew his claws, rubbing them as he recalled what theoretical support the teachers still needed.
Old Wang seized the opportunity and immediately fawned over Jiang Xia, offering him a cup of hot tea, then grabbing his hand and giving him a "professional massage": "Take a break, little Jiang? It's good to balance work and rest..."
Seeing Old Wang's eager (and inquisitive) eyes, Jiang Xia decided to go along with it: "Okay..."
Actually, Jiang Xia saw that there was no new information coming from the other side, and guessed that the older generation was busy "digesting" (actually verifying) the "future knowledge" he had thrown out. So he went along with it and got up to tell Lao Wang some gossip about that strange boat.
Jiang Xia was actually wondering to himself: He hadn't thought much about it at first, but now that he had some time to think about it, this thing suddenly appeared? That doesn't make sense!
Logically speaking, welding a few vertical steel plates under the bottom of a boat is something that, unless the bald eagle has gotten its head stuck in a door, or it's just a makeshift "fishing net cutting" toy to fool the bald guy, otherwise... that thing is almost certainly a hydrofoil!
What exactly is a hydrofoil?
Simply put, water is the tiptoeing ballerina of the boat world! It has a few wing-like things underneath (hydrofoils), and when it runs, it forcefully "lifts" itself out of the water, leaving only those "wings" sticking in the water to paddle.
Ordinary boats: They move along the water with great difficulty, as if they are dragging mud and water.
Hydrofoil: By using hydrofoils to lift the hull, the water resistance is instantly reduced by more than half! It shoots off in a flash, with a speed that leaves other boats of the same size far behind!
To put it simply, it's like equipping the boat with a "floating suspension system." While others are still "bathing" in the water, it's already riding on a "water seesaw," heading towards poetry (speed) and distant places!
Among hydrofoils, the top star is undoubtedly the "Pegasus-class missile boat" from the United States. Back then, this little boat was touted as having "Cold War black technology," "the fastest assassin on the surface," and "a deadly little throwing knife"... its aura was dazzling.
However… Jiang Xia scratched his head: Wasn't this thing only officially put into service in the 70s or 80s? Oh right! If it was deployed in the 70s, it might already be under secret development. It's quite possible they'll produce a prototype! After all, they don't have a "cheat code" like me; development has to be done step by step…
Thinking of this, Jiang Xia's "storytelling" switch was turned on again.
"If I'm not mistaken, this should be an experimental ship. I just don't know why the U.S. is suddenly being so generous as to give it away as a gift..." Jiang Xia stroked his chin, looking deep in thought.
"Then...then haven't we gotten a great deal this time?!" Old Wang's breathing quickened, and his eyes gleamed.
"Tsk...it's hard to say," Jiang Xia paused for a few seconds, sensing that things weren't so simple. "Tell me about the situation in more detail! The more detailed the better!"
Old Wang then realized that Jiang Xia had only heard the gist of the story before rushing off to "debate Jiangdong." He immediately recounted all the details of the battle that he had learned to Jiang Xia, like spilling beans.
As Jiang Xia listened, he mentally ranted: To say hydrofoils are useless? That's absolutely dishonest! Just their speed of over forty knots is enough to make anyone drool! Not to mention the treasure inside—the gas turbine!
Exactly! Without a gas turbine, what kind of hydrofoil can you play with? Do you really think it's as easy as a skateboard? You think you can just bounce around on it and fly off? Dream on!
But! Even Little Grey knows this kind of "cutting-edge technology" is precious, so why would Bald Eagle be so generous? Would it really expose its true colors in a single conflict just to save face? That doesn't make sense!
You should know that the gas turbine blueprints in the space shop are ridiculously expensive; Little Ao Mao's points accumulated so far are only enough for a fraction of that.
The Pegasus-class missile boat looks cool and stylish, bursting with technological sophistication, but its cost... it's truly mind-boggling! Back in the early design phase of 72, the budget was already a staggering $1800 million per vessel!
When the first vessel was actually built, wow, the bill skyrocketed to $6500 million!
$65 million in the 1970s—that's a huge sum! Even the US Navy itself was terrified at the time, and they only managed to build six ships!
Ultimately, because these things were too delicate and expensive, and didn't match their development path of "big ships and big guns" (actually aircraft carrier groups), they were ruthlessly "exiled" to the Caribbean Sea to do the job of chasing pirates...
(The massive warships mentioned here are actually a trap set by the US. They later built an all-nuclear fleet and took it on a world tour, fooling the Russians into painstakingly building super cruisers, while they themselves turned around and started building aircraft carriers. It's really cunning.)
However, Jiang Xia thought about it again and realized that the manufacturer of this small boat was that notoriously "fragile Boeing," which seemed a little more reasonable? After all, they often use "technology bundling" when selling airplanes.
But... something still feels off!
Could this be... a grand scheme by the bald eagle? Are they deliberately showing us the "extraordinary" nature of these hydrofoils, then eagerly imitating them, so as to lead us astray from our proper development path?
Just like how they steer the alliance astray?
Is this a tempting technological trap set for us?
Yes! That's it! I bet that gas turbine on the submarine is a useless piece of junk, and the impeller inside is probably crooked and broken!
"Pah!" Jiang Xia shook his head violently, his ahoge (cowlick) twitching three times. "I'm not falling for it! Even if I turn back to play with the wooden torpedo boats the Alliance gave me, I won't follow your lead!"
Hehe! I'll make sure you all waste your time!
He seemed to already see the bald eagle's conspiracy fail, and he proudly shook his tuft of hair.
If Uncle Jin, far away, knew that this brilliant man had conjured up such a "bald eagle technology conspiracy theory," he would probably just laugh bitterly and frantically pluck his hair: "I went through all that trouble to bring back this high-tech stuff to my hometown, and you just want to throw it aside and play with your wooden boat?!"
Huh? Why am I pulling my own hair? Don't run away, little ahoge!
I'll pluck that tuft of hair out of your head and turn it into a dandelion!