Manifold microchannel cold plates for high-power GPU packages
Liquid cold plates for GPU packages that will dissipate 10 kW and more, and a design framework for manifold microchannel cold plates at large package footprints.
The problem
Power per GPU package is rising quickly. Next-generation AI accelerators are expected to dissipate 10 kW or more from a single package, at heat fluxes well above 100 W/cm². A cold plate for such a package needs a thermal resistance on the order of 3 K/kW, at a pressure drop that a data center coolant loop can supply.
Manifold microchannel cold plates are well suited to this. A manifold layer distributes coolant into short microchannel segments and collects it again, which gives high heat transfer at low pressure drop.
Initial work: design optimization for GaN power electronics
The first part of this work, published in the International Journal of Heat and Mass Transfer (2026), established a Pareto-based design optimization framework for a U-type manifold microchannel cooler and applied it to a specific case: a printed circuit board with six GaN power devices. It is a problem with a small footprint and very high local heat flux.
A conjugate heat transfer model driven by the heat map of the six devices was used to optimize the channel, fin and manifold geometry for thermal resistance and pressure drop, with the design constrained to remain machinable. The optimized copper cooler was CNC machined and tested on the GaN board, with junction temperatures measured in situ from the calibrated on-resistance of the devices.
- Pressure drop 70–98 % lower and thermal resistance 19–26 % lower than the baseline cooler, over 0.5–6 L/min.
- Heat fluxes up to 208 W/cm², with a cooling coefficient of performance up to 1.6 × 10⁶.
- Simulations within 3 % of experiment at all but the lowest flow rate.
- Extrapolated to a 75 mm × 75 mm package, a junction-to-coolant resistance near 3.5 K/kW.
I am a co-first author of this paper and presented the work at ASME InterPACK 2026.
GPU-scale cold plates
The next step is the GPU. We are designing manifold microchannel cold plates at GPU scale, around 40 mm, for current hardware such as the NVIDIA RTX 5090. The cold plates are being fabricated by both additive and conventional manufacturing, with several manufacturing partners, and tested on GPU hardware.
A design framework for large-area cold plates
Manifold microchannel cold plates have not been systematically developed for large package footprints, where distributing coolant evenly across the plate becomes the main difficulty. We are developing a design framework for large-area manifold microchannel cold plates aimed at 10 kW-class packages. It combines computational design, reduced-order modeling and machine-learning-assisted optimization. The details will follow publication.
Status
Ongoing. Design, fabrication and testing are in progress.