What Is Immersion Cooling? What Are Its Advantages? And The Difference Between Two-phase And Single-phase Immersion Cooling?

Views: 544 Author: Site Editor Publish Time: Origin: Site

Immersion cooling is a typical type of direct contact cooling with liquid, which is to submerge the heated ASIC mining machines in the cooling liquid (coolant) and rely on the two-way flow of liquid to take away the heat generated by the mining machines running high-speed operation. The heated coolant will then be cooled down through a cooling system and circulates back to the liquid immersion cooling tanks.

The Immersion cooling

Compared to conventional cooling methods, immersion cooling has the advantages of heat dissipation efficiency, optimizing energy efficiency ratio, low noise, reducing investment and operating costs, abridging time consumption and complexity in site construction.

In the meantime, with the removal of redundant peripherals, a substantial amount of equipment footprint is no longer essential, hence a more flexible data center layout can be realized, miners will not be bound by the restriction in location selection before, nor the costs coming along with tract leveling or graveling.

Liquid immersion cooling is mainly divided into single-phase immersion cooling and two-phase immersion cooling, what is the difference between them?

Two-phase immersion cooling 

Servers or other electronic components are submerged in a thermally conductive dielectric liquid or coolant. Heat is removed from the system by circulating the liquid into direct contact with hot components, whereby the liquid undergoes a low-temperature evaporation process to cool the hot components and transfer the heat out of the liquid. The gas is cooled again by a heat exchanging method (such as a condenser coil) to allow return flow into the larger liquid volume.

Two-phase immersion cooling

Single-phase immersion cooling

In single-phase cooling, the electronic components are submerged directly in the dielectric fluid, which is placed in a sealed but easily accessible vessel, and heat is transferred from the electronic components to the fluid. A circulation pump is typically used to divert the heated fluid to a heat exchanger, where it is cooled and circulated back to the vessel.

Single-phase immersion cooling

Difference between the two

1. Cost

The biggest cost difference between single - and two-phase relates to the coolant. 

Two-Phase Cooling

Fluorocarbon-based two-phase coolants typically cost an order of magnitude more than hydrocarbon-based ones. Additional costs become significant when over 300 gallons of the evaporative fluid are used in a single rack. Moreover, fluid for two-phase immersion requires a fully sealed enclosure as to avoid losses. When it comes to maintenance, the complexity of the enclosure often creates trouble in access, let alone the costs related to fluid top-up. Furthermore, prolonged exposure to the vapor can cause health and environmental concerns since the fluorocarbon-based substance is highly regulated.

Single-Phase Cooling

Although it requires a pump to keep the coolant circulating through the system, single-phase immersion cooling wins the complexity category. Single-phase immersion cooling system has a simpler submerged cylinder design, making fluid containment easier to achieve, and has fewer concerns about material compatibility and contaminants in the fluid than two-phase immersion cooling. 

Efficiency & Operating Expenses

The efficiency levels of both methods are significantly higher when comparing them to a traditional air-cooled data center.

Two-Phase Cooling

The current research suggests that two-phase cooling may have a slight edge over single-phase cooling, claiming a PUE (Power Usage Efficiency) of 1.02 as opposed to 1.03.

While two-phase systems are energy-efficient, pulling maintenance on them can be complicated. As aforesaid, to access the servers, operators must unseal the enclosure while trying to minimize coolant loss and inhalation of vapor.

power udage efficiency comparision

Single-Phase Cooling

To contrast single-phase cooling with the relative energy inefficiency of non-immersion-cooled systems, 1.02-1.03 PUE is definitely convincing enough to champion the prize. In terms of fluid application, the hydrocarbon-based coolant is usually non-evaporative, odorless and non-toxic. Thus, The argument swings in favor of single-phase cooling when levels of maintenance are taken into consideration. Typically, single-phase immersion cooling solutions require much less maintenance and are much easier to access and repair if adjustments are needed.

Cooling Capacity & High-Density Performance

Two-Phase Cooling

Two-phase coolants can typically support extreme rack densities, higher heat transfer efficiency can be achieved through the boiling process (through state transforming from liquid to gas ), some providers claim to support up to 250 kW in a single rack (kilowatts [kW] per cabinet), regardless of finding commercially available hardware that will even reach 100 kW.

kw per rack potential

Single-Phase Cooling

By contrast, BBZ’s Drawer Bath Tank is capable of handling 200 kW per rack (let alone only 6 ASIC machines with a maximum power of 5-6kw each, are fitted in one single tank) when attached to a chilled water system, which is more than enough cooling performance for the foreseeable industry demand to future-proof.

To conclude, it is biased to criticize that one is better than the other between the two approaches discussed herein. However, it is fair to say that the basic principles of single-phase immersion cooling transcend the conventional ones to the next level, but in the meantime eliminate the drawbacks of two-phase immersion cooling which seems to be complex, costly and over-engineered for the majority of data center cooling needs today.

In need of immersion cooling tank?

If you are looking for an immersion cooling tank, you are in the right place. BBZ provides mining machine containers, mining transformers, and mining hosting facility services. If you want to know more about our immersion cooling tank, you can contact us!


Contact Us



Company Name