When a high electric field is applied to an insulating liquid (refrigerant, oil, etc.), flow occurs due to Coulomb force. EHD pumps utilizing this phenomenon have no moving parts, and thus are characterized by the absence of vibration and noise compared to conventional pumps using impellers. In order to develop heat transport devices using EHD pumps, we are clarifying high-performance electrodes and pump geometries through numerical analysis and experiments, and applying them to pumps and flow control. We are also investigating the scale effect of the size of EHD conduction pumps for application to flow control on a micro-nano scale. We are also conducting fundamental research on pumps applicable to liquid-vapor two-phase flow using dielectrophoretic forces acting at the liquid-vapor interface instead of Coulomb forces, and on phase change enhancement using vibration.