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A heat pipe model of electrohydrodynamical (EHD) enhancement heat transfer has been designed and made. The insulating liquid was selected as working fluid and the copper wire whose diameter was 1mm was used as the high voltage electrode. The temperature in the inlet and outlet of both the vaporization section and the condensation section, the saturation vapor pressure inside this model were measured respectively under different applied dc voltage and different tilt angle, that is, the vaporization section was placed higher than the condensation section. The experiment results indicate that the circumfluence between the condensation section and the vaporization section was improved with the increase of the applied dc voltage. Such EHD enhancement heat transfer technology can be practically employed in the heat transfer engineering, and has some reference values for the investigation of heat pipes used in the case of anti-gravity.

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The paper presents a technique of UHF method with an antenna as a coupling sensor to detect the signals of partial discharge excited within the high voltage apparatus with co-axial cylinder electrode at a defect site. The experimental modeling is designed and the detecting devices concluding the receiving antenna are manufactured. The defects caused PD failures in the high volt apparatus are artificially simulated in different configurations under different pressures. Through the research work the valuable results are gained. The characteristics of the antenna response to the kinds PD signals in the high voltage apparatus with co-axle cylinder electrode at a defect site and the PD pulse curves are shown in this paper.. The facts are proved that the method is powerful to detecting the PD and locating the defect site.