Muh-Rong Wang

Unmanned aerial vehicles (UAVs) have become popular for military applications as well as for use in structural inspection, weather monitoring, and festival demonstrations. Suitable landing gears to ensure that the UAV can take off and land safely are important when the price of the cargo and UAV increase. A lightweight and high-strength landing gear is desirable to overcome accidents during service. Composite materials are a promising, excellent solution for this purpose. This study demonstrated the design, numerical analysis (Ansys), manufacture, and experimental verification (LabVIEW) of a composite landing gear for a UAV. In particular, landing gears with different carbon fiber-reinforced polymer (CFRP) composite fiber orientations were analyzed, manufactured, and experimentally verified in this study.

This paper describes the production of metal powder using an atomiser with internal-mixing mechanisms under supersonic configuration. The atomiser is designed with a convergent–divergent channel and a confinement section. The atomisation gas was first accelerated to supersonic speed through the annular convergent–divergent channel. It was then introduced to the confinement section and impinged onto the melt injected from the delivery tube. The interaction between the atomisation gas and the melt in the confinement section resulted in the atomisation of the melt. The confinement of the region downstream of the delivery tube is called the internal-mixing zone. Flow expansion was observed in the internal-mixing zone as the supersonic flow came out from the divergent section. The liquid phase was confined by the high-speed gas flow in the centre of the atomiser. The velocity of atomisation gas can further increase through the flow expansion and the high-velocity region of atomisation gas is extended. The resu...