Data Center Cooling Days 2026: Q&A RecapBy Mark MacDonald, Thermal Systems Lead

We had a great time presenting at this summer’s Data Center Cooling Days 2026! It is inspiring to see so many thermal hardware enthusiasts assembled to exchange ideas and hear about new technologies and cooling strategies. In our session this year, we discussed the challenge of “thermal orphans” that can be created as the data center industry pivots to full liquid cooling to meet the cooling challenges of AI and OpEx pressures to lower cost.

Thermal orphans are typically submodules on the server platform, such as network interface cards (NICs), non-volatile storage solid state drives (SSDs), power supply units (PSUs), or other custom PCIe modules. These modules sit far from the xPU and memory complex within the server. In a fully liquid cooled rack, there is little airflow at these locations to manage the modest module heat loads. There is a strong desire from platform designers to find alternative cooling solutions that don’t require the added cost, complexity, or leakage risk of connecting them to the primary liquid cooling stream.

At Ventiva, we are exploring the use of ionic cooling modules that move air using electrohydrodynamics (EHD) to cool thermal orphans in a server environment. Our ultra-compact ionic cooling devices effectively circulate cooling air through the thermal orphans, managing heat without the need for bulky fans or extraneous liquid connections.

In our Data Center Cooling Days 2026 presentation, we showed implementation examples for a NIC module and an SSD module. There was a lot of interest in this new technology approach – in fact, we had so many questions that we didn’t have time to answer them all during the session. So, I thought I would respond here to a couple of the questions we couldn’t get to during the Q&A:

Q: Does the ionic cooling module generate ozone?
Yes, a portion of the air is ionized in any electrohydrodynamic (EHD) air mover and the creation of some level of ozone is unavoidable. However, Ventiva has developed a proprietary low-cost solution for controlling ozone when our ionic cooling module is deployed in customer applications so that ozone levels are well within regulatory and safety limits.

Q: How did you model the ionic cooler? Prescribed air flow rate?
We do our system level flow modeling using FloTherm, an industry standard CFD tool for electronics cooling applications. Within the tool, we do not prescribe the device’s flow rate, rather we employ a full pressure-flow curve (“PQ curve”), similar to how you would specify a fan or blower. In our case, our PQ curve is empirically calibrated to actual device performance measured using an Air Flow Chamber (AFC) or wind tunnel.

We do have the in-house capability to predict the air flow created within the ionic cooling module a priori using multiphysics models that incorporate electromagnetic fields, gas phase chemistry and electrochemistry, and fluid mechanics (we use COMSOL for that purpose), but these highly detailed models are unnecessarily cumbersome for analysis of a full server platform, so we use FloTherm for all platform-level work. The multiphysics modeling is used for design optimization of the EHD device itself.

Q: What is the cost of an ionic cooler?
Final cost depends on the number of ionic cooling device(s) used in the platform implementation as well as the number of power supply unit(s) required to support them. It also depends on the purchase volume, etc. At a high level, the total cost should be competitive with traditional fan/blower cooling solutions.

Q: Could a fluid other than air be used instead? For example, could a coolant liquid to be propelled (with appropriated sealing around emitter)?
While EHD forces can be used in a variety of ways to move liquids, the underlying physics are somewhat different (usually a dielectric fluid with a charge-carrying impurity is used and no ionizing corona is established). There are also a number of techniques using electrostatic acceleration of atomized sprays of dielectric liquids for things like spacecraft propulsion. Either way, these liquid-moving devices are constructed significantly differently than our air-moving ionic cooling module. If you are interested in learning more about ionic driven liquid flows, a literature search on “electrohydrodynamic” or “electrokinetic” pumping/propulsion will reveal a vast amount of academic research in these fascinating areas (as well as a smaller amount of commercial work!).

Q: How was the ionic cooling inlet boundary condition implemented? Directly known values of velocity at inlet?
As mentioned above, CFD modeling of cooling platforms using our ionic cooling modules uses empirically calibrated values for pressure and flow through our device. In this way, we can consider a wide variety of system-level boundary conditions representing realistic internal server conditions for fully liquid-cooled and hybrid liquid/air-cooled server configurations. If you have specific follow up questions on how to set up and specify an ionic cooling module for your own application, please reach out to us directly – we’ll be happy to help!

It was a pleasure presenting at Data Center Cooling Days 2026. Thank you all for your interest and we look forward to presenting more exciting updates in the future!