Sword of Light: Humanoid Self-Propelled Artillery

Chapter 242 The Fighter Jet That Drinks Sweet Potato Liquor

However, at this moment, Wang Gensheng said to Lu Haotian:
"By the way, does your flight school have aviation gasoline specifically for aircraft engines? In order to keep the planes at Xuzhou Airport and reduce the number of bomber sorties, our Marine Corps blew up the airport's fuel depot! So now all the fighter jets and bombers at the airport are running low on fuel!"

Upon hearing Wang Gensheng's words, Lu Haotian immediately smiled wryly and said:
"Our flight school is also running low on fuel. Although we obtained a considerable amount of fuel at Shengyang Airport, it's not enough to sustain us for an extended period because we don't have a refinery to produce aviation gasoline. However, while we can't produce fuel, we've figured out a way to use alcohol as a substitute! We just need to slightly modify and enlarge the fuel injectors on the fighter jet engines to use alcohol instead of aviation gasoline."

As Wang Gensheng listened to Lu Haotian's words, he couldn't help but recall the plot of the movie "The Age of White Clouds," in which the flight school's oil depot was blown up by spies.

With no fuel left, the flight school began experimenting with using alcohol as a substitute for aviation gasoline.

In fact, the Japanese had tried this method during the War of Resistance Against Japan. However, since the Japanese had not developed any oil fields in the country, and the United States blocked the Japanese fuel supply, their planes, tanks, and other equipment were rendered useless.

So, in order to avoid their planes going to dust, the Japanese began to research using alcohol fuel instead. However, after crashing more than thirty fighter planes, the Japanese abandoned the idea of ​​using alcohol instead of fuel.

However, this time, with the support of the flight school principal, they began to use alcohol instead of aviation gasoline for ground experiments.

After numerous experiments by Japanese experts who had joined the flight school, it was discovered that by simply enlarging the aircraft's fuel injection nozzle, alcohol could be used to replace fuel.

The reason why the Japanese failed to use alcohol as a substitute for fuel was mainly due to the insufficient calorific value of alcohol.

Because alcohol has only 68 percent of the calorific value of gasoline, or about two-thirds, the engine power is naturally limited during takeoff or when high-power operation is required.

By enlarging the nozzle opening, more alcohol is injected, thus increasing the amount of alcohol injected into the cylinder, making it possible to use alcohol instead of gasoline.

It can also allow fighter jets to take off without running on gasoline; they can run on sweet potato liquor and still fly.

While ethanol fuel can replace gasoline, it has a significant drawback: its low calorific value means that a tank of fuel in a fighter jet can only fly 1,500 kilometers with aviation gasoline, but only 1,000 kilometers with ethanol, greatly reducing the aircraft's range.

However, alcohol fuel, also known as ethanol fuel, has a characteristic that gasoline cannot match, and this characteristic was only discovered decades later.

Decades from now, efficient and environmentally friendly energy solutions will be a global research focus. Among the many noteworthy innovations, ethanol fuel, with its unique environmental characteristics and superior performance, is gradually changing our traditional understanding of automotive fuels. This seemingly ordinary liquid actually has the potential to significantly improve vehicle performance, and its contribution to reducing global greenhouse gas emissions makes it an eco-friendly energy option for our planet.

That's right! Besides being environmentally friendly, ethanol fuel can also improve the performance of car engines!

The reason ethanol fuel can improve power output is due to its significantly higher octane rating than conventional gasoline. Specifically, pure ethanol has an octane rating of 109, which is even higher than aviation gasoline with an octane rating of 100, which the United States spent a great deal of effort producing during World War II.

It's important to know that octane rating is a crucial indicator of a fuel's resistance to knocking. A high octane rating means the fuel can withstand higher compression ratios without spontaneous combustion, which is vital for engine performance. This is similar to the reason why the United States used aviation gasoline with an octane rating of 100 during World War II.

Ethanol's high octane rating allows engine designers to increase the engine's compression ratio, thereby improving combustion efficiency and enhancing the engine's power output.

Furthermore, for engines equipped with turbochargers, the high octane rating of ethanol allows for higher boost pressures without increasing the risk of knocking, which also helps to further improve engine power and performance.

Another advantage of ethanol in engines is that it can more effectively absorb heat from the surrounding cylinders during vaporization, a process known as the heat of vaporization. This effect is similar to how sweat helps the body dissipate heat in hot weather.

This property of ethanol is particularly evident in direct injection engines. By lowering cylinder temperature, ethanol not only improves engine performance but also helps to increase engine efficiency and lifespan.

For example, before Wang Gensheng's time travel, a car company was using ethanol fuel in a twin-turbocharged engine. This engine could produce 380 horsepower and 400 pound-feet of torque at 5,000 rpm under boost, while using gasoline, the power output was only 190 horsepower and 200 pound-feet of torque. This difference was partly due to the engine being able to operate at a higher compression ratio when using ethanol fuel, thus naturally generating more energy.

At the same time, the heat-absorbing properties of alcohol can help the engine achieve better heat dissipation and prevent the engine from experiencing heat fade.

Therefore, when ethanol fuel is used in fighter jets to replace aviation fuel, it can actually enable the aircraft engine to unleash greater power.

There's no need to worry about the engine overheating when the engine speed is too high.

Therefore, from the perspective of pursuing high engine performance, alcohol, or ethanol fuel, is the most suitable, even more so than gasoline with an octane rating of 100.

After all, given the octane rating of alcohol, it's possible to design engines with high compression ratios that are compatible with alcohol fuel.

Unfortunately, even with a high compression ratio, the performance improvement is limited to a maximum of 100%.

In the coming decades, jet engines will be the way to go, easily achieving several times or even dozens of times the power output of traditional engines.

This is evident in the fact that piston-engine fighter jets have a takeoff weight of only four or five tons, while jet fighters can easily reach a takeoff weight of thirty or forty tons, and piston-engine fighter jets are unlikely to reach supersonic speeds.

The fact that jet-powered fighters can easily achieve three times the speed of sound demonstrates the performance difference between the two.

However, jet engines in the United States and the Soviet Union are only just beginning to develop, and the United States doesn't even have the capability to manufacture piston engines, let alone jet engines with higher precision requirements.

(End of this chapter)