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161.
《中国航空学报》2020,33(8):2176-2188
This paper describes the general optimization design method of Solar-Powered Unmanned Aerial Vehicle which priority considering propulsion system planning. Based on the traditional solar powered aircraft design method, the propulsion system top-level target parameters which affect the path planning are integrated into the general optimization design. According to the typical mission requirements of Solar-Powered Unmanned Aerial Vehicle, considering the design variables such as wing area, aspect ratio, design mission date and so on, the general optimization is carried out with the minimum aircraft weight as the optimization objective. The influence of wing area and aspect ratio on the optimal design results is analyzed and compared with the traditional design method. The results show that the general design method of Solar-Powered Unmanned Aerial Vehicle for priority considering propulsion system can greatly reduce the electricity demand of energy storage battery, greatly reduce the aircraft weight of Solar-Powered Unmanned Aerial Vehicle. 相似文献
162.
A data-driven health indicator extraction method for aircraft air conditioning system health monitoring 总被引:2,自引:0,他引:2
Prognostics and Health Management (PHM) has become a very important tool in modern commercial aircraft. Considering limited built-in sensing devices on the legacy aircraft model, one of the challenges for airborne system health monitoring is to find an appropriate health indicator that is highly related to the actual degradation state of the system. This paper proposed a novel health indicator extraction method based on the available sensor parameters for the health monitoring of Air Conditioning System (ACS) of a legacy commercial aircraft model. Firstly, a specific Airplane Condition Monitoring System (ACMS) report for ACS health monitoring is defined. Then a non-parametric modeling technique is adopted to calculate the health indicator based on the raw ACMS report data. The proposed method is validated on a single-aisle commercial aircraft widely used for short and medium-haul routes, using more than 6000 ACMS reports collected from a fleet of aircraft during one year. The case study result shows that the proposed health indicator can effectively characterize the degradation state of the ACS, which can provide valuable information for proactive maintenance plan in advance. 相似文献
163.
人力资源是企业发展动力的源泉,是可持续发展的根本保障。本文根据中国通用航空发展的态势和飞机修理厂的现状与发展目标,对飞机修理厂提出了规划要求和适应发展需要的应对措施。 相似文献
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High-efficiency aircraft antiskid brake control algorithm via runway condition identification based on an on-off valve array 总被引:1,自引:1,他引:1
The aircraft antiskid braking system is an important hydraulic system for preventing tire bursts and ensuring safe take-off and landing. The brake system adjusts the force applied on the brake discs by controlling the brake pressure. Traditional aircraft antiskid braking systems achieve antiskid performance by controlling the braking pressure with an electrohydraulic servo valve. Because the pilot stage of an electrohydraulic servo valve is easily blocked by carbonized hydraulic oil, the servo valve would become a dangerous weak point for aircraft safety. This paper proposes a new approach that uses an on-off valve array to replace the servo valve for pressure control. Based on this new pressure control component, an efficient antiskid control algorithm that can utilize this discontinuous feature is proposed. Furthermore, the algorithm has the ability to identify the runway circumstances. To overcome the discontinuity in the process of using an on-off valve array, the Filippov framework is introduced. The conditions of convergence of the system are also discussed. The results of the digital simulations and the hardware-in-the-loop (HIL) braking experiments are used to verify the efficiency and stability of the proposed control algorithm. The method also proves that the on-off valve array can replace the servo valve perfectly as a new type of antiskid braking pressure control component. 相似文献
166.
通过对广州民航职院1100余名学生的问卷调查,了解了学生对高技能人才的认识情况,掌握了民航高技能人才在培养目标、专业设置、课程结构、教学改革、师资水平的培养现状及存在的问题,并针对调查结果,提出了加强民航高技能人才培养的对策与建议。 相似文献
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童谷生%孙良新%刘英卫 《宇航材料工艺》2002,32(5):20-24,29
系统归纳并分析了国内外30年来在复合材料胶接修补研究中所取得的效果,以及最近10年的最新研究动态,涉及损伤修补设计,有限元精确分析,智能修补等,并指出了研究中值得注意的问题。 相似文献
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