【摘要】：直升機(jī)已成為現(xiàn)代陸、海上人命和財產(chǎn)救助的一種重要裝備。救助絞車系統(tǒng)是救助直升機(jī)上的關(guān)鍵裝備之一,受力復(fù)雜,其結(jié)構(gòu)設(shè)計影響救助過程中救生員和絞車手操作便利性、安全性和可靠性。本文基于人機(jī)工程學(xué)、拓?fù)鋬?yōu)化、模態(tài)分析、疲勞分析理論,利用ANSYS Workbenc h有限元分析軟件,進(jìn)行了絞車支架的結(jié)構(gòu)優(yōu)化設(shè)計和分析,以提高其操作便利性、動態(tài)和疲勞特性。主要內(nèi)容包括：(1)在分析直升機(jī)救助過程中工況和受力特點的基礎(chǔ)上,建立絞車及支架受力分析模型,給出五種典型工況,作為絞車及支架設(shè)計載荷工況條件,為絞車支架設(shè)計奠定基礎(chǔ)；基于人機(jī)工程學(xué)原理,結(jié)合我國絞車手、救生員身體標(biāo)準(zhǔn),進(jìn)行絞車支架的結(jié)構(gòu)尺寸及外形設(shè)計,并利用ANSYS Workbench軟件對其在五種典型受力工況下的結(jié)構(gòu)強度進(jìn)行分析。分析結(jié)果表明,支架最大位移和應(yīng)力值都發(fā)生在載荷后偏30°工況,分別為1.25 mm和246.37 Mpa,均滿足結(jié)構(gòu)要求。(2)基于拓?fù)鋬?yōu)化理論,利用ANSYS Workbench軟件,對救助直升機(jī)絞車支架進(jìn)行拓?fù)鋬?yōu)化設(shè)計。設(shè)計案例分析表明,在應(yīng)力和位移滿足結(jié)構(gòu)要求的前提下,拓?fù)鋬?yōu)化后絞車支架的重量減輕12.5%,這將有助于提高直升機(jī)飛行的氣動性能,減少飛行過程中的能耗和成本。(3)基于ANSYS Workbench軟件,對拓?fù)鋬?yōu)化后的直升機(jī)救助絞車支架進(jìn)行模態(tài)分析,提取絞車支架前六階固有模態(tài)和振型,與直升機(jī)旋翼旋轉(zhuǎn)頻率進(jìn)行對比。結(jié)果表明,六階約束模態(tài)基頻的頻率為475.24 HZ,振型為橫向平面一階整體擺動,而旋翼的激勵頻率為24 HZ,絞車支架與旋翼滿足不發(fā)生共振的條件。(4)引入疲勞強度縮減因子,并利用Goodman曲線,修正絞車支架材料的S-N曲線,獲得考慮形狀、尺寸、表面狀態(tài)、受載狀況、平均應(yīng)力等影響因素的絞車支架的S-N曲線；輸入ANSYS Workbench中,分析獲得絞車支架在加載脈動循環(huán)載荷下的壽命和安全系數(shù)云圖。分析結(jié)果表明,在施加波峰值為極限工況下的脈動循環(huán)載荷后,對應(yīng)循環(huán)次數(shù)大于107次,絞車支架具有無限壽命,滿足疲勞強度要求。
[Abstract]:Helicopters have become an important equipment for modern land, sea life and property rescue. Rescue winch system is one of the key equipment on rescue helicopter, and its structure design affects the convenience, safety and reliability of lifeguard and winch driver in the rescue process. In this paper, based on ergonomics, topology optimization, modal analysis and fatigue analysis theory, the structural optimization design and analysis of winch support are carried out by using ANSYS Workbenc h finite element analysis software, in order to improve its operation convenience, dynamic and fatigue characteristics. The main contents are as follows: (1) on the basis of analyzing the working conditions and stress characteristics of helicopter rescue, the stress analysis model of winch and support is established, and five typical working conditions are given as the load working conditions of winch and support design, which lays the foundation for the design of winch support; Based on the principle of ergonomics and the body standard of winch driver and lifeguard in China, the structural size and shape of winch support are designed, and the structural strength of winch support under five typical stress conditions is analyzed by ANSYS Workbench software. The analysis results show that the maximum displacement and stress value of the support occur at 30 擄after load, which meet the structural requirements of 1.25 mm and 246.37 Mpa, respectively. (2) based on the topology optimization theory and ANSYS Workbench software, the topology optimization design of the support of rescue helicopter winch is carried out. The design case analysis shows that under the premise that the stress and displacement meet the structural requirements, the weight of the winch support can be reduced by 12.5% after topology optimization, which will help to improve the pneumatic performance of the helicopter flight and reduce the energy consumption and cost during the flight. (3) based on ANSYS Workbench software, the modal analysis of the helicopter rescue winch support after topology optimization is carried out, and the first six natural modes and vibration modes of the winch support are extracted. The rotating frequency of helicopter rotor is compared with that of helicopter rotor. The results show that the fundamental frequency of the sixth constrained mode is 475.24 HZ, while the excitation frequency of the rotor is 24 HZ, winch support and rotor satisfying the condition of no resonance. (4) the fatigue strength reduction factor is introduced, and the S 鈮，

本文編號：2497631