Asetek Emma V2: State-of-the-art closed-loop liquid cooling

It’s not just the closed impeller design that enables the Emma V2 pump to outperform its predecessors, though: another important factor is the optimisation of the pump housing and flow paths therein. All liquid channels have been carefully tuned with an organic shape and smoother surface finish to minimise flow impedance and reduce unnecessary turbulence. With less impedance inside the channels, higher flow rates and pressure head can be leveraged at the cold plate to achieve superior thermal performance.

The Emma V2 cold plate is manufactured from 99.95% high-purity CU1100 copper and features a large 32.5 by 22.5 mm array of skived microfins. The density of the microfins has been further increased compared to the previous Sigrid generation coolers in order to make the best use of the superior hydraulic performance of the Emma V2 pump. A central groove within the microfin array works in tandem with the integrated injection plate to ensure even liquid distribution across the cooling fins as well as maximum penetration depth:

Another key element of closed-loop liquid coolers is, of course, the radiator. Asetek’s Emma V2 coolers use 20 FPI (Fins per Inch) radiators that have been optimised for maximum cooling performance at quiet fan speeds. Unlike some other radiators on the market, Asetek uses non-louvered fins. While louvered fins can provide improved thermal performance at high air velocities, the air velocities produced by quiet fans such as the NF-A12x25 G2 and NF-A14x25 G2 are too low to take advantage of this potential benefit. Since louvered fins also introduce extra flow impedance, they would actually lead to lower performance when using quiet, low-speed fans.

Asetek’s Emma V2 coolers use high-quality braided EPDM (Ethylene Propylene Diene Monomer) tubes with an extremely low permeation rate in order to minimise liquid loss and ensure optimal long-term stability. While some all-in-one liquid coolers use more flexible tubes, using softer materials can come at the expense of increased permeation or risk of buckling, so this option was ruled out in order to ensure that the NL-LC1 safely reach the lifetime expectations required to be covered by Noctua’s 6-year warranty period.

Another important factor that affects the lifetime of all-in-one liquid coolers is the coolant. Emma V2 units use a mixture of demineralised water and propylene glycol with excellent antifreeze, anti-corrosion and anti-biological performance. Unlike automotive antifreeze coolants, this mixture is non-toxic and safe to handle, even if a system is accidentally cut open and the user comes into contact with the fluid. Fully compliant with environmental regulations such as RoHS and REACH, the working fluid can be disposed of through the household wastewater system. At the same time, the included propylene glycol guarantees that the system can safely withstand adverse environmental conditions in storage or transport (-20°C to +70°C).

Over years of usage in millions of systems, the anti-corrosion and anti-biological formulation of Asetek’s coolant has proven highly effective in preventing galvanic corrosion and gunk-buildup, thereby ensuring maximum system lifespan and performance stability. All Asetek Emma V2 coolers are certified to meet international safety standards such as IEC 62368-1 / UL 62368-1 and undergo rigorous QC testing before shipment.

In sum, the engineering innovations of Asetek’s Emma V2 platform have enabled it to set new standards in terms of pump efficiency as well as thermal and acoustic performance while providing the same industry leading quality and long-term stability as previous generations of Asetek coolers.