A new autonomous underwater vehicle (AUV) has high maneuverability near the bottom and a direction turnaround ability, called the autonomous underwater helicopter (AUH). This paper numerically investigates the hydrodynamic performance of the AUH. A Reynolds-Averaged Navier–Stokes (RANS) equation, a computational fluid dynamics (CFD) technique, is applied to analyze the AUH’s behavior. Investigations of the AUH’s hydrodynamic characteristics become more obvious with a service speed in the range of 0.4–1.2 m/s. For the same velocity condition, the resistance of the AUH increases, and the irregular eddy at the rear of the AUH expands with changes in the angles of attack and the length/height ratio. Essential design characteristics including pressure, velocity distribution, and velocity streamlines are shown and analyzed. These insights can be used as a guideline to reduce drag force and optimize the AUH profile for future designs. It has great potential for improving the AUH’s control algorithms.

In this study, the effect of cooling channel design on the warpage of the injection molding product is numerically investigated. Different cooling channel layouts have been carried out. The results show that the design of cooling channel layout has a strong effect on the warpage of injection molding product. By the using baffle cooling channel, the cross-sectional area for the coolant is significantly enhanced. The heat accumulation at the corner of the part is then eliminated. Finally, the warpage of product considerably drops, and the quality of product is improved.