Director: The special effects are too expensive, so I had to make real shots

Chapter 55 Immersion Phase Change Liquid Cooling Technology

Being able to sit at the same table with Professor Zheng and eat at an event is not something ordinary young people can do.

Some people eat at the children's table.

Xu Nuo ate at the old man's table.

It can be seen that Xu Nuo is extraordinary.

During the meeting, Professor Zheng talked with Xu Nuo about the details of building a supercomputer.

From Shenwei Technology's many-core processors to the selection of heat dissipation technology for the entire supercomputing, both of them conducted in-depth discussions.

Especially the heat dissipation of supercomputers is an unavoidable problem.

Although Xu Nuo's Nanshan smart villa, which has already started construction, is next to Nanshan Lake, and there are two big rivers in Yuzhou not far away, the requirements of the natural environment are quite satisfactory, but the cooling system of the supercomputer itself is also An essential part.

"Xiao Xu, what kind of heat dissipation method are you going to use to build a supercomputer this time?"

"Traditional air-cooled and water-cooled air-conditioning cooling methods have begun to become somewhat inadequate for the development of supercomputing. I think immersion liquid cooling should be the best choice at present."

Xu Nuo thought for a while and replied.

The way of liquid cooling and heat dissipation is indeed more advantageous than traditional heat dissipation.

For example, it is more extreme in terms of energy saving.

Because the refrigerant will be in direct contact with the heating element, the heat exchange efficiency will be higher, and full natural cooling can be achieved, and the system PUE will be <1.05.

And the power density has been greatly improved, and the power density of a single cabinet can reach more than 60kW.

The heat dissipation of the device is also more uniform. If the liquid cooling of the full immersion method is adopted, the internal temperature field of the server will be more uniform, and the reliability of the device will be more guaranteed.

In fact, there is no need to worry about the risk of leakage for liquid cooling. As long as an insulating and environmentally friendly cooling liquid is used, even if a leakage occurs, there is basically no risk to the infrastructure hardware and the external environment.

Noise is definitely unavoidable in traditional heat dissipation methods, but with liquid cooling, the noise will become even lower. All components of the server can be dissipated through liquid cooling, and the fanless design is implemented inside, and the noise of full-load operation can be <45dB.

Therefore, most of the supercomputers completed in recent years will choose to use immersion phase change liquid cooling technology.

"Well, immersion liquid cooling is indeed a good option, but it will be more expensive in terms of cost."

Professor Zheng nodded.

"It doesn't matter." Xu Nuo said calmly: "For our company, these costs are not a big problem, but in terms of immersion phase change liquid cooling technology, I have to ask Professor Zheng, what do you think? Do we use single-phase immersion liquid cooling, or two-phase immersion liquid cooling?"

"Single-phase and two-phase immersion liquid cooling technologies have their own advantages and disadvantages. It depends on whether you choose stability or heat dissipation efficiency."

There are still differences in principle between single-phase immersion liquid cooling and two-phase immersion liquid cooling.

In single-phase immersion liquid cooling.

With electronic fluorinated fluids maintained in a liquid state, the electronic components are submerged directly in the dielectric fluid, which is placed in a sealed but easily accessible container, and heat is transferred from the electronic components to the liquid.

A circulation pump is usually used to flow the heated e-fluorinated fluid to a heat exchanger where it is cooled and circulated back to the container.

The coolant remains in a liquid state during the circulation and heat dissipation process without phase change.

After the low-temperature coolant takes away the heat, the temperature rises, and the elevated coolant flows to other areas to re-cool and complete the cycle
Single-phase liquid cooling requires a higher boiling point of the cooling liquid, so that the control of cooling liquid volatilization and loss will be relatively simple, and the compatibility with the components of computer equipment is better, and there is no need to replenish cooling liquid frequently. This is a single-phase immersion liquid Cold stability advantage.

However, compared with two-phase immersion liquid cooling, the heat dissipation efficiency is lower.

Two-phase immersion liquid cooling is different.

Through the boiling and condensation process of the electronic fluorinated liquid, the heat transfer efficiency of the liquid will be improved exponentially, and the electronic components are directly immersed in the dielectric liquid in the container, which is sealed but easy to handle.

Inside the container, heat is transferred from the electronic components to the liquid, causing the liquid to boil to produce steam.

The steam condenses on the heat exchanger in the container and transfers the heat to the facility cooling water that circulates in the data center, and the cooling liquid undergoes a phase change during the circulation and heat dissipation process.

The cooling liquid takes away the heat of the electronic components and undergoes a phase change to gasify, and the gaseous cooling liquid is condensed by other equipment and becomes liquid again.

However, the two-phase immersion liquid cooling is not perfect, because in the process of this phase change, the cooling liquid will escape when it evaporates into a gaseous state, so there are certain requirements for the sealing of the container.

But it can’t be too sealed. To prevent accidents due to interruption of the cooling system, certain safety facilities need to be installed. The safety requirements are much higher than those of single-phase immersion liquid cooling.

"For me, it is more appropriate for the heat dissipation to be relatively stable."

Xu Nuo thought about it, and felt that the heat dissipation stability was more suitable for his supercomputer.

After all, the supercomputing that I am about to complete in a smart villa does not pursue the ultimate computing power, and the cost is only about 4 million yuan. The world's supercomputing ranking cannot even enter the top [-], so there is no need for cooling efficiency. The ultimate pursuit.

Only those top supercomputers in the world will generate unimaginable energy consumption during operation, so cooling efficiency is very important at this time.

"If you are looking for stability, then choose single-phase immersion liquid cooling."

Professor Zheng suggested: "At that time, we will adopt single-phase immersion liquid cooling technology for your supercomputer, so that the heat dissipation stability of the supercomputer will be highly guaranteed during operation, but Xiao Xu, Are you sure you don't pursue high heat dissipation efficiency?"

"Uh-huh."

Xu Nuo nodded, and decided to use single-phase immersion liquid cooling.

With a supercomputing capability of tens of billions of calculations per second, and a stable cooling method, it is a very stable "home" for Guan Ju.

"Well, there is also energy consumption. I think you are mentally prepared for the super-calculated electricity consumption?"

Professor Zheng asked about the power consumption of the supercomputer: "How do you plan to solve it?"

After all, it is a supercomputer used by enterprises, and it is not the same as the National Supercomputing Center.

Like the National Supercomputing Center, some can even directly use nuclear power plants for power supply.

Take Sunway TaihuLight as an example.

Its power consumption per second is 4.2 degrees.

What is the concept? Sunway TaihuLight will consume 1.5 kilowatt-hours of electricity when it is turned on for an hour. If calculated according to the normal electricity price, the electricity bill for a day will be 30 million.

Therefore, the National Supercomputing Center generally has a dedicated power supply method.

However, for the supercomputer of the enterprise, it has to bear the electricity bill by itself.

Even the supercomputer that Xu Nuo wants to build uses a Shenwei 15000 processor worth about 26010 yuan and about a dozen computing cabinets, the power consumption is quite terrifying.

But Xu Nuo pondered.

Guan Ju can be regarded as a mature AI, should he learn to earn electricity bills by himself?
(End of this chapter)