Our digital world is expanding at an unprecedented speed, and the data center is trying to handle all our Netflix revelry and online transactions. Behind the scenes, there is a crucial factor that helps these data centers run smoothly: the cooling system. 
In terms of cooling capacity, the liquid cooler is far superior to air cooling, and it is efficient and cost-effective. In this paper, we will introduce two types of liquid cooling: immersion type and conductive type (directly to the chip).
Liquid cooling: basics
The data center is crowded with servers in racks, and each server calculates data at lightning speed. All these processes generate a lot of heat. liquid cooler exposes some or all servers to the coolant running through a pipeline network. When a liquid reaches a hot spot, it will absorb excess heat.
The now-warmed liquid then returns to the heat exchanger, which transfers heat from the liquid (usually the water loop connected to the cooling system). As the heat dissipates, the liquid flows back to the equipment and repeats this cycle.
The thermal conductivity of liquid is much better than air, which makes it a more effective way to absorb excess heat. It is more energy-saving and consumes 10-50% less energy than traditional air cooling. But as we have noticed, there are many different forms of liquid cooler solutions. Direct-to-Chip (DTC) cooling is one of the most common methods. It circulates liquid coolant through channels or cold plates, which are in direct contact with hot parts, such as computers and graphics processing units (CPU and gpu).
On the other hand, immersion liquid coolers completely immerse IT equipment in non-conductive liquid coolants. The coolant absorbs heat from all components, not just specific components, and takes it to the heat exchanger located outside the immersion tank. The heat energy is transferred to a separate cooling system, such as a chilled water circuit. After that, the coolant returns to the immersion tank and circulates. However, it should be noted that although this technology can cool the hottest immersed components very effectively, other components may still need supplementary air cooling.
Both methods are effective ways to keep the server cool at the source. However, let's discuss the differences between these two methods to better determine which method is most suitable for your needs.
Comparative analysis: immersion and direct cooling to the chip
Both liquid immersion and direct chip cooling are aimed at solving the heat generated by high-performance processors. But they have unique characteristics that make them unique. When choosing the right solution for your data center, you should consider the following points:
thermal resistance
Although these two cooling methods are significantly improved compared with the traditional cooling air, the direct liquid cooler of the chip dissipates a little more heat than the liquid immersion cooling. This is because the temperature of the fluid circulating through the direct contact chip system is usually lower than that in the immersion cooling system, thus providing lower resistance and transferring more heat from the chip-level components. However, directly cooling the chip will not cool other components such as the hard disk. You need to provide additional cooling means for other equipment-usually frozen thus offsetting many potential benefits of operational efficiency.
cost
If your organization currently has an existing chilled air infrastructure in the data center, you need to consider the initial setup cost of an immersion liquid cooler, because you will need to invest in immersion water tanks and coolant circulation systems. But in the long run, this investment is worthwhile, because it can significantly reduce energy consumption, and if you design and build a data center from scratch, the immersed infrastructure requirements are simpler (no air processors, coolers, row cooling, etc.), which can significantly reduce capital expenditure. Eliminating fans and isolating IT equipment from dust, static electricity, condensation, and vibration can also prolong the service life of the equipment.
Direct liquid cooler to the chip requires a lot of upfront investment in specialized equipment and infrastructure, as well as a coolant distribution unit, which circulates the fluid to each CPU or GPU, and so on. However, like immersion, it can effectively use energy, reduce power consumption, and save a lot of costs in the long run. However, because direct access to the chip only cools a single component, it does not provide a significant reduction in energy consumption, because you still need to supplement the cooling for the rest of your equipment.