The message was sent to the Nanzhou, and this time the waiting time was a bit long, almost an hour later, before receiving a reply from the Nanzhou.

Gao Kai on the screen had a serious face: "Leishan, your ship is moving away from the sun, with the direction and speed of your ship, it is too reluctant to set the cordon at forty percent, in order to ensure safety, it is best to increase it by another ten percentage points." ”

Ye Han's whole person is not good, but after thinking about it carefully, he has to admit that Gao Kai's worries are indeed justified.

Under normal circumstances, the fuel warning line of a space battleship is between 15 and 30 percent, and the specific amount must consider the speed, direction, load and output power of the thrusters.

He set the fuel warning line at 40 percent, leaving a very high margin, and to put it simply, this fuel is enough for the Leishan to fly from the asteroid belt to Beiyue Island and back.

However, as Gao Kai said, the Thunder Mountain is flying towards Jupiter's orbit, and it must slow down before returning, and after such a toss, 40% of the fuel is enough.

Ye Han thought for a while before replying: "Nanzhou, the call has been received, in view of the current situation of our ship, there is no need to raise the cordon immediately, if the speed of my ship continues to increase, I will raise the cordon to fifty ......percent at an appropriate time."

He had a lot of plans in mind for returning to the sea, but no matter which plan it was, it had to depend on the specific situation at that time, rather than staying in the bridge and thinking about it casually, and he could come up with a return plan that suited all the circumstances.

However, Ye Han already agreed with Gao Kai's suggestion in his heart, and it would not work if he didn't agree, it was really the fuel that was too critical, this thing was not only related to the power of the Leishan, but also involved another important issue: range.

If it is a surface ship, the range of the ship can be calculated after a very simple calculation, depending on the speed and fuel consumption of the ship.

However, the space battleship is in space without resistance, and if the situation facing the Thunder Mountain is relatively calm for a period of time in the future, then the battleship only needs a little fuel to adjust its direction, and it can fly far by inertia alone.

On the other hand, if the situation is turbulent and a lot of acceleration and deceleration and direction change must be carried out, then the Leishan will consume a large amount of fuel every day, and the reserve fuel will not last long.

Ye Han couldn't help but wonder in his heart, if only the output power of the thruster was a little higher!

He came up with the idea because the efficiency of nuclear-powered engines was simply too low.

The so-called nuclear power engine, in fact, should be called a nuclear power propulsion, this thing has too high requirements for materials, especially the reaction chamber that withstands explosions, especially the strength of the material.

A miniature nuclear explosion is also a nuclear explosion, and the reaction chamber must not only withstand the temperature of the miniature nuclear explosion, but also absorb the impact of the miniature nuclear explosion, feed back the impact to the battleship, and finally become the force of the battleship's advance.

The new engine of the Thunder Mountain is actually not a big deal, but a new alloy was accidentally obtained in a laboratory while researching the materials of the super engine.

In addition to working on materials, Ye Han has also heard of some more out-of-the-way methods.

For example, a cooling system is installed outside the reaction chamber and the reaction chamber is cooled by liquid nitrogen.

The idea is very good, and it is quite operable, but the reaction chamber is not a bad thing, on one side is close to minus 200 degrees of liquid nitrogen, on the other side is a continuous miniature nuclear explosion, the temperature difference between the inside and outside of the cavity is not less than two or three thousand degrees, no matter what material the cavity is, it can't withstand such a violent torture.

It's also a good idea to replace liquid nitrogen with other coolants, but the cooling effect is really not very good and it doesn't do much at all.

It's just a train of thought.

Ye Han also heard that some people got inspiration from the jet engine of a fighter jet and wanted to install an afterburner system on a nuclear engine.

To put it simply, at the same time as the fuel ball is launched, a "combustion agent" is added to the reaction chamber, which absorbs the energy of the miniature nuclear explosion and then plasmaizes, and the plasma is sprayed out along the reaction chamber, and finally achieves the effect of boosting and accelerating.

It is said that this method can increase the efficiency of nuclear engines by several times or even more than ten times, and theoretically, it can even catch up with the propulsion efficiency of chemical rockets!

To tell the truth, Ye Han thinks that this idea is really good, the principle and technology are mature, but plasma is also called plasma, this thing not only runs outside the reaction chamber, but also likes to drill into the reaction chamber, and the magnetic field must be used to control the spray direction of this thing, so as not to pour plasma into the reaction chamber.

First the afterburner system, then the magnetic beam equipment, and the "fuel tank" to store the accelerant, the engine structure was several times more complex in an instant, and the repair and maintenance costs skyrocketed.

Because of these miscellaneous reasons, countries know that this is a good way, and have carried out experiments in this area, but so far, no country has built a practical afterburner system.

After thinking about it, none of the methods currently mastered by mankind can be used in nuclear engines, and it is estimated that human warships will be inseparable from nuclear engines for a long time in the future.

Unless, a breakthrough in the research of super engines!

But according to Ye Han's understanding, the research of super engines has been difficult, and he has not figured out the detailed principle until today, only knowing that this thing is the same as human thrusters, and it also uses the principle of recoil.

But how exactly it works and what fuel is used is still a mystery.

If only the Thunder Mountain could fit a few miniature super engines...... Tsk, there is a problem with running all over the solar system in one go, and the exhausted aliens can't catch up, so what fuel is not fuel?

After thinking about it, I received a communication from Gao Kai again.

Gao Kai on the screen looked helpless: "Ye Han, I just received an order from Beiyuezhou, and the top asked me to fully cooperate with your actions, not only Nanzhou, but also the No. 3 and No. 4 bases have also received orders, and there are several other warships on the way, a total of six, but there are only two of ours, and the remaining ones are all sent by the base group...... This time it was really a big game, not only going deep behind enemy lines, but also attracting the international fleet ......"

Ye Han was also a little stunned when he received this news, since the second fleet returned to Earth, the international fleet has not moved, why is he willing to send the battleship out at this time?

He vaguely felt that this matter was not so simple.

In fact, it's not that complicated at all, the ownership of the asteroid belt is related to the safety of the entire human race, a large number of aliens have landed on the earth, if the alien fleet is allowed to hit the outer space of the earth, human beings are not completely finished?

Don't look at the Northern Capital and Washington have been fighting openly and secretly, but there is a limit to the struggle, at this juncture, the overall interests of mankind are more important than anything else, and no matter how much dirt there is behind it, it is impossible to tear each other down at this time.