中国飞机防除冰技术专利态势分析

选择"中国国家知识产权局"中文专利数据库作为数据源,建立防除冰技术专利数据库,然后从防除冰技术专利现状、重点专利技术和申请人等方面对防除冰技术专利进行了深入分析,并对比分析了国内外防除冰技术专利申请情况,讨论了国内防除冰技术专利的发展态势,可为国内相关企业进行防除冰技术研究提供参考。     

民机防冰系统自然结冰试飞技术研究

结合某型民机自然结冰条件下防冰系统的试飞,对试飞所需的测试改装工作进行了总结,并对试飞前需进行的各种安全性评估进行了总结说明,明确了试飞中需考虑的各种构型情况,提出一套循序渐进的自然结冰试飞方法。同时提出了试飞中结冰气象参数的可接受性判据,最后针对自然结冰试飞中结冰气象参数的处理提出了分段等效处理的方法。     

推进式螺旋桨飞行中桨叶温度测量与尾气防冰性能评估

为研究某推进式布局螺旋桨表面温度分布特性,评估发动机尾气防冰功能,对螺旋桨进行了飞行中的温度测量试验,在桨叶上布置了Pt100热电阻和K型热电偶,通过无线近距遥测系统实现信号传输,测量螺旋桨在不同高度和发动机状态飞行时的表面温度,结果表明桨叶前缘尾气显著影响区温度随半径增加先升高后降低,桨叶最大厚度处温度则随半径增大呈先降低后升高趋势;飞行高度增加会导致桨叶温度显著下降,在同一高度内增大燃气发生器转速可引起桨叶温度小幅升高。根据相关标准和文献得到桨叶表面临界结冰判据,表明在5km螺旋桨防冰功能有效,在7km部分位置存在结冰风险,在8.5km防冰功能完全失效。     

Flight safety oriented ice shape modulation using distributed plasma actuator units

Ice accretion on the wings seriously threatens the flight safety of an aircraft. From the perspectives of ensuring flight safety and saving power consumption, the ice shape modulation method using distributed plasma is proposed. Distributed plasma actuator units are designed to modulate the spanwise continuous ice at the leading edge into periodically segmented ice pieces, forming a wavy leading edge. Both airfoil and scaled aircraft model, with continuous and modulated ice, are experimentally investigated and simulated. Compared with the continuous ice, ice shape modulation can significantly improve the aerodynamic performance, flight control characteristics and flight safety. This method can save about half electric power, which is very beneficial for application.     

民用客机机翼热气防冰系统问题初探

简单介绍了热气防冰系统的特点及工作原理,同时对前缘缝翼笛形管的两种基本布置方式进行了描述,最后对波音737系列、空客320系列以及空客340等飞机的机翼热气防冰系统进行了介绍和对比分析。     

Experimental study of an anti-icing method over an airfoil based on pulsed dielectric barrier discharge plasma

Aircraft icing has long been a plague to aviation for its serious threat to flight safety. Even though lots of methods for anti-icing have been in use or studied for quite a long time, new methods are still in great demand for both civil and military aircraft. The current study in this paper uses widely used Dielectric Barrier Discharge(DBD) plasma actuation to anti-ice on a NACA0012 airfoil model with a chord length of 53.5 cm in a closed-circuit icing wind tunnel. An actuator was installed at the leading edge of the airfoil model, and actuated by a pulsed low-temperature plasma power source. The actuator has two types of layout, a striped electrode layout and a meshy electrode layout.The ice accretion process or anti-icing process was recorded by a CCD camera and an infrared camera. Instantaneous pictures and infrared contours show that both types of DBD plasma actuators have the ability for anti-ice under a freestream velocity of 90 m/s, a static temperature of -7℃,an Median Volume droplet Diameter(MVD) of 20 lm, and an Liquid Water Content(LWC) of 0.5 g/m~3. The detected variations of temperatures with time at specific locations reveal that the temperatures oscillate for some time after spraying at first, and then tend to be nearly constant values.This shows that the key point of the anti-icing mechanism with DBD plasma actuation is to achieve a thermal equilibrium on the model surface. Besides, the power consumption in the anti-icing process was estimated in this paper by Lissajous figures measured by an oscilloscope, and it is lower than those of existing anti-icing methods. The experimental results presented in this paper indicate that the DBD plasma anti-icing method is a promising technique in the future.     

超疏水和超润滑防冰表面的制备技术概述

对超疏水和超润滑防冰表面的制备方法进行了综述。分析了制备防冰表面的重要意义,重点介绍了化学涂层、表面微纳结构和液体润滑层3种获得超疏水和超润滑防冰表面方法的研究现状,并对防冰表面的发展进行了展望。     

Experimental study of curvature effects on jet impingement heat transfer on concave surfaces

Experimental study of the local and average heat transfer characteristics of a single round jet impinging on the concave surfaces was conducted in this work to gain in-depth knowledge of the curvature effects. The experiments were conducted by employing a piccolo tube with one sin-gle jet hole over a wide range of parameters: jet Reynolds number from 27000 to 130000, relative nozzle to surface distance from 3.3 to 30, and relative surface curvature from 0.005 to 0.030. Exper-imental results indicate that the surface curvature has opposite effects on heat transfer characteris-tics. On one hand, an increase of relative nozzle to surface distance (increasing jet diameter in fact) enhances the average heat transfer around the surface for the same curved surface. On the other hand, the average Nusselt number decreases as relative nozzle to surface distance increases for a fixed jet diameter. Finally, experimental data-based correlations of the average Nusselt number over the curved surface were obtained with consideration of surface curvature effect. This work con-tributes to a better understanding of the curvature effects on heat transfer of a round jet impinge-ment on concave surfaces, which is of high importance to the design of the aircraft anti-icing system.     

机翼防冰自动作动功能的逻辑设计及验证

首先从适航规章出发提出了某大型民机的机翼防冰自动作动功能要求,包括结冰探测、起飞抑制、温度抑制、机组操作指令和发动机引气状态等子功能,以及实现各子功能所需的信号及信号状态组合;接着设计了满足功能要求的基于主导式结冰探测的自动作动组合逻辑电路,推导了逻辑真值表;最后采用matlab软件simulink模块搭建了自动作动组合逻辑电路,数字验证的工作波形与真值表一致,表明设计的自动作动组合逻辑电路能够实现机翼防冰的自动作动功能。     

民用航空发动机进气道防冰系统设计方法研究

民用航空发动机进气道防冰系统为发动机在结冰条件下运行提供了安全保障,中国民航总局颁布的适航条款中对民用航空发动机在结冰环境中的运行也提出了安全性要求,但国内针对进气道防冰系统设计工作开展的研究较少,本文针对民用航空发动机进气道笛形管防冰系统的设计,介绍了国内外热气防冰系统的研究进展,阐述了进气道防冰系统的设计依据、设计方法、优化方法及试验验证方法,为民用航空发动机进气道防冰系统设计相关工作提供参考.