Ionic wind vs fans for electronics cooling: thickness, noise, vibration, airflow and power compared, with when to use each. Talk to our engineers.
For over forty years, mechanical fans have been the default active cooling solution for electronics. They work. They are cheap. Supply chains produce billions of them annually. So why would anyone consider replacing them?
Because the design constraints of modern electronics are making fans increasingly impractical. Devices are getting thinner. Acoustic requirements are getting stricter. Reliability expectations are getting longer. And in many emerging applications — from wearable medical devices to embedded automotive electronics — fans simply cannot fit the design envelope.
Ionic wind offers a fundamentally different approach: moving air with electric fields instead of spinning blades. This article provides an engineering-level comparison of the two technologies across the parameters that matter for electronics thermal design.
This is where ionic wind's advantage is most dramatic.
The smallest commercially available axial fans are approximately 5 mm thick (e.g., 15x15x5 mm micro-fans). Below this threshold, blade aerodynamics degrade rapidly — shorter blades produce less pressure rise, and the hub-to-tip ratio becomes unfavorable. Centrifugal blowers can go somewhat thinner (down to about 3.5 mm), but still face fundamental limits from bearing dimensions and impeller geometry.
DBD plasma actuators can be fabricated at thicknesses below 1 mm. The entire electrode-dielectric-electrode stack is comparable in thickness to a few layers of a printed circuit board. This means ionic wind devices can be integrated into spaces where fans physically cannot exist: inside smartphone housings, between PCB layers, on the surface of chip packages, or within AR/VR headset frames.
For product designers working on devices thinner than 5 mm with active cooling requirements, ionic wind is not merely competitive with fans — it is the only viable forced-convection option.
Mechanical fans generate noise through multiple mechanisms: blade-passing frequency tones, turbulent boundary layer noise on blade surfaces, motor electromagnetic noise, and structural vibrations transmitted to the housing. Even well-designed fans in consumer electronics typically produce 25–40 dBA at operating speed.
Ionic wind devices generate airflow through ion-neutral momentum transfer — a process with no moving surfaces, no blade wake interactions, and no motor harmonics. Because nothing rotates, there is no blade-pass tone, motor harmonic or bearing noise. Acoustic output depends on drive voltage and frequency and should be measured in the target enclosure.
This difference matters enormously in several application categories. Recording studios and broadcast environments require near-silent electronics. Medical devices used in clinical settings need to operate without contributing to the already-high ambient noise levels in hospitals. Open-plan office environments amplify the aggregate noise from dozens of cooling fans into a meaningful productivity drain.
The noise character of ionic wind is different in kind, not just in level.
A mechanical fan is a rotating machine with bearings, a motor with windings, and blades that experience cyclic stress. Each of these components has a wear-out failure mode:
DBD plasma actuators have no moving parts, no bearings, and no mechanical wear surfaces. The primary aging mechanism is dielectric degradation, for which we have not yet published a characterised figure. With no friction surfaces, there is no lubrication to degrade and no gradual performance decline from bearing wear.
For applications requiring long unattended operation (remote edge computing nodes, telecommunications infrastructure), the absence of mechanical wear is a significant reliability advantage.
Every rotating machine produces vibration. Fan vibration causes problems ranging from cosmetic (audible buzzing) to functional (interference with vibration-sensitive components like hard disk drives and optical systems) to structural (fatigue of mounting hardware and solder joints over extended operation).
Fans in data centers have been documented as a measurable source of vibration-induced bit error rates in conventional hard disk drives. In optical systems, fan-induced vibration can degrade imaging performance.
Ionic wind devices produce zero mechanical vibration. This makes them suitable for:
In raw airflow volume, mechanical fans maintain a significant advantage. A 40 mm axial fan can move 3–10 CFM of air. A 120 mm server fan can exceed 100 CFM. Current ionic wind devices typically generate bulk air velocities of 1–4 m/s with volumetric flow rates well below those of equivalent-sized fans.
This means ionic wind is not currently suited for applications requiring high-volume air movement: server rack cooling, desktop gaming PCs, industrial ventilation, or applications with higher per-module heat loads unless extended-surface heat sinks are used.
However, ionic wind's lower flow velocities are partially offset by two factors:
Boundary layer thinning. Because DBD actuators produce a wall jet that flows directly along the heated surface, they are exceptionally effective at disrupting the thermal boundary layer — the thin layer of stagnant air that insulates the surface from the bulk airflow. A fan-driven flow typically approaches the surface at some angle and may not efficiently thin this boundary layer across the entire heat source.
Point-of-need delivery. Fans push air into a general volume. Ionic wind actuators can be placed directly on or adjacent to the heat source, delivering cooling exactly where it is needed without ductwork or airflow path design. This spatial efficiency means that less total airflow can achieve equivalent thermal performance in constrained geometries.
Air density also matters: at altitude a fan moves less mass, while DBD actuator thrust follows a different pressure curve. See avionics thermal management.
Small fans (15–40 mm) typically consume 0.5–5 W. DBD actuator power depends on electrode length, drive voltage and frequency, and should be compared at equal heat removal for the specific geometry.
The difference becomes more interesting at the system level. Fans require driver electronics, mounting hardware, and often ductwork or shrouds to direct airflow. These system-level elements add weight, cost, and design complexity. Ionic wind actuators, being printed onto substrates, require only a compact high-voltage power supply — which can itself be integrated onto a PCB.
For battery-powered devices, where every milliwatt matters, the efficiency comparison depends on the specific thermal load and geometric constraints. In thin devices where a fan simply cannot operate efficiently (because the blade length is too short to generate useful pressure), ionic wind provides cooling capability that a fan physically cannot deliver at any power level.
Fans are susceptible to dust accumulation on blades and in bearings, which degrades performance over time and can eventually cause failure. Cleaning or replacing fans in sealed devices is often impractical.
Ionic wind devices face a different contamination challenge: the electric field can attract charged dust particles to the electrodes. However, DBD plasma actuators can be designed with self-cleaning voltage reversal cycles, and because they are solid-state with no mechanical gaps, they are inherently less susceptible to particulate fouling than bearing-based systems.
Use mechanical fans when: - Per-module heat load is high and extended-surface heat sinks are not an option - Device thickness allows 5+ mm for the fan assembly - Noise is not a primary constraint - The application environment is clean and well-controlled - Cost is the primary selection criterion (fans benefit from massive economies of scale)
Use ionic wind when: - The device must be thinner than 5 mm - Tonal or bearing noise is unacceptable - Zero vibration is critical - Bearing wear-out is the limiting failure mode - The per-module heat load is low - The form factor is non-planar or geometrically constrained
Use both when: - A heat pipe or vapor chamber handles heat spreading, ionic wind handles the final heat rejection in a constrained space - Spot-cooling of specific components supplements bulk fan-driven airflow
For more on how ionic wind compares to other cooling technologies including thermoelectric coolers, see: Plasma Actuators vs Thermoelectric Coolers. For a concrete example of where fan penalties become disqualifying, see drone electronics cooling.