عنوان مقاله [English]
نویسندگان [English]چکیده [English]
In this paper a mini turbofan engine which would be used in a UAV, is considered to be in the early and reverse design phase and reliability and maintainability analysis have been performed. To overcome the lack of data in design phase, it is used generic data or expert judgments. Then simulation process utilizing reliability block diagrams is performed. The results involve reliability evaluation of system, reliability importance and availability. The engine has less than 98 percent reliability in 126 flight hours. A reliability allocation method has been utilized to improve the reliability measure to 98 percent in 250 flight hours. An availability analysis utilizing Monte Carlo simulation has been done and 0.753 percent as mean availability has been estimated during 3 years usage and maintenance policies have been proposed for 3 years usage of the engine. Results reveal that the oil and fuel filters, pumps and the disks and blades of the rotating subsystems are the most critical parts of the engine.
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