An oscillating heat pipe (OHP) is an effective heat transfer device for the thermal management of electronic devices. However, the heat transfer mechanism of the OHP was not fully understood due to its complicated operation characteristics. In this paper, the thermal performance of an OHP was experimentally studied. The condensation and evaporation temperature variations were monitored under different heat inputs and were then used to evaluate the OHP system operating characteristics. Thermal resistance was used as a key parameter to evaluate the thermal performance of the OHP system. The results indicated that as the heat input increased from 25 to 100 W, the average thermal resistance decreased while the stable evaporating and condensing temperatures increased. The equivalent heat transfer coefficient was derived theoretically. It showed that the reciprocal of the radial heat transfer coefficient increased with increasing liquid film thickness. Based on this result, an empirical correlation was proposed to evaluate the thermal resistance of an OHP system. This correlation was validated using both the experimental data provided in this study and the data collected from the open literature. The comparison results indicated that the proposed empirical correlation could reasonably predict the thermal resistance under different filling ratios and heat inputs.

Particle accumulation increases the pressure drop and reduces the long-term performance of micro-electrostatic precipitators (MESPs). This study quantifies wet-spray regeneration responses for a single MESP geometry intended for residential ventilation. The effects of spray pressure, spray angle, nozzle-to-module distance, and washing duration were evaluated using single-factor and orthogonal experiments. Increasing the spray pressure from 0.1 to 0.3 MPa decreased the post-cleaning pressure drop from 38.5 to 16.5 Pa and increased the pressure recovery rate from 54.9% to 95.3%, while further increases produced diminishing benefits. The operating ranges identified for nozzle-to-module distance and washing duration were 50–100 mm and 20–30 s, respectively. Within the selected factor levels, the factor order was nozzle-to-module distance > spray pressure > washing duration > spray angle. The preferred parameter combination identified by orthogonal range analysis was 0.4 MPa, 30°, 50 mm, and 30 s, based on the factor-level means. This combination requires confirmation using the same module and dust-loading conditions. The numerical comparison gave a relative deviation of 5.5% at 0.3 MPa and provided flow-field context for the parameter trends. The findings link the four spray parameters to residual airflow resistance and post-cleaning particle-collection efficiency, providing operating data for residential MESP regeneration.