Study on gas-liquid flow characteristics of buffers in the landing gear of a certain type of UAV landing gear lowering stage

Abstract

When designing the retractable landing gear of an aircraft oil-gas mixed type，the medium flow characteristics between the inner cavities should be fully considered. The damping aperture and fuel filling amount of a certain UAV landing gear buffer is taken as the research object，and the single factor experimental method is used to analyze the changes of gas-liquid flow inside the buffer caused by each factor. The gas-liquid characteristics of the buffer under different damping apertures and oil filling amounts in the lowering stage are simulated and calculated by Fluent software. The results show that the damping hole oil flow during the landing gear lowering process is only related to the size of the pore size，not affected by the oil filling amount of the buffer. Under the 637 mL oil filling required by this type of UAV，the buffer damping aperture should be greater than 6 mm. For other types of landing gear buffers，when the oil filling amount is determined，the gas-liquid filling of the buffer that meets the lowering stage should be used as one of the buffer damping hole design criteria.

Keywords

• buffer
• damping pore size
• gas-liquid filling time
• oil filling capacity
• gas-liquid exchange