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Coolants are widely used to dissipate grinding heat in conventional grinding. This process, however, is not satisfactory as coolants often lose efficacy in grinding due to film boiling and can result in adverse health and environment effects. The present paper put forward the concept of a rotating heat pipe grinding wheel, attempting to reduce or eliminate the coolant amount and realize green machining. The heat transfer performance of rotating heat pipe grinding wheel was studied by using volume of fluid method in ANSYS/FLUENT. The influence of the input heat flux, filling ratio and rotational speed were investigated by a simulation method. Results show that the appropriate heat flux range for the rotating heat pipe grinding wheel was from 2000 to 100,000 W/m2, the ideal filling ratio was 50% and the rise of the rotational speed turned out to weaken the heat transfer coefficient. Finally, dry grinding experiments on Ti-6Al-4V were performed and the temperatures in both the rotating heat pipe and the grinding contact zone were monitored. The new designed rotating heat pipe grinding wheel showed a good prospect for application to green grinding of difficult-to-cut materials.

Bone drilling is a common surgical operation, which often causes an increase in bone temperature. A temperature above 47 °C for 60 s is the critical temperature that can be allowed in bone drilling because of thermal bone osteonecrosis. Therefore, thermal management in bone drilling by a rotating heat pipe was proposed in this study. A new rotating heat pipe drill was designed, and its heat transfer mechanism and thermal management performance was investigated at occasions with different input heat flux and rotational speed. Results show that boiling and convection heat transfer occurred in the evaporator and film condensation appears in the condenser. The thermal resistance decreases with the increase of the rotational speed at the range from 1200 to 2000 rpm and it decreases as the input heat flux rises from 5000 to 10,000 W/m2 and increases at 20,000 W/m2. The temperature on the drill tip was found to be 46.9 °C with an input heat flux of 8000 W/m2 and a rotational speed of 2000 rpm. The new designed rotating heat pipe drill showed a good prospect for application to bone drilling operations.

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With the rapid development of information science and technology, the demand for computer data processing is increasing, resulting in the rapid growth of the demand for high-power and high-performance solid-state drives (SSDs). The stable operation of SSDs plays an important role in ensuring the reliable working conditions and appropriate temperature of information technology equipment, rack servers, and related facilities. However, SSDs usually have significant heat emissions, putting forward higher requirements for temperature and humidity control, and consequently the heat sink system for cooling is essential to maintain the proper working state of SSDs. In this paper, a new type of thin heat pipe (THP) heat sink is proposed, and the heat transfer performance and cooling effect are experimentally and numerically studied. The numerical results are compared with experimental results, which showed an error within 5%. Single and double heat pipes were investigated under different input powers (from 5 W to 50 W) and different placement angles between 0° and 90°. The heat transfer performance of the new heat sink is analyzed by the startup performance, the evaporator temperature, and the total thermal resistance. The results show that the new double THPs with a 90° angle have a great advantage in the heat transfer performance of SSDs. The research is of great significance for the design and optimization of the SSDs’ cooling system in practical applications.