基于记忆合金的高超声速进气道流动控制方法及验证

发布时间：2018-01-02 04:37

本文关键词：基于记忆合金的高超声速进气道流动控制方法及验证　出处：《南京航空航天大学》2015年博士论文　论文类型：学位论文

【摘要】：高超声速进气道作为超燃冲压发动机的重要组成部分,显著影响着推进系统的性能。由于其工作在较宽的工作马赫数范围,非设计点性能往往难以兼顾。因此,为了改善设计/非设计点综合性能,需要引入措施对前体激波系调节和通道内激波/边界层干扰实施必要的控制。随着形状记忆合金材料的不断发展,其在进气道调节领域展现出较大的应用潜力,为此本文对基于局部记忆合金的高超声速进气道流动控制方法及关键气动问题进行了探索研究。根据高超声速进气道外压缩激波的调节需求,研究了通过局部改变进气道前体压缩面的外压缩激波调节技术,建立了由压缩面轮廓获得弯曲激波轮廓、由激波轮廓反求压缩曲面的计算方法,并据此研究了压缩面局部鼓包对外压缩激波的影响规律,提出了鼓包设计的原则。针对肩部膨胀波干扰下的高超声速进气道唇罩激波/边界层干扰现象进行了研究,发现在膨胀波影响下,目前广泛使用的激波/边界层干扰特性经验公式在多数情况无法获得满意的结果。进一步的研究表明,膨胀波与唇罩激波相互干扰是一个在空间逐渐变化的过程,其存在四种不同的作用机制,据此得到了膨胀波抑制唇罩激波/边界层相互干扰的有利区间。针对唇罩激波/边界层干扰现象,提出了基于二维可变形鼓包的新型控制方法,研究了其流动控制机理和控制规律,并将鼓包应用于高超声速进气道中。研究表明,其流动控制机理主要包括鼓包迎风面的预压缩效应、外凸段的消波效应以及膨胀扇对边界层加速效应。在有限宽度通道内,激波/边界层干扰具有显著的三维特性,此时的控制机理还包括鼓包分流作用对侧板下扫低能流聚集现象的抑制效应。一般,当激波入射在鼓包外凸面时其对激波/边界层干扰具有较好的控制效果。对于多道激波/边界层干扰现象,为使鼓包的控制效果达到最佳,应保证各道唇罩激波均入射在鼓包的外凸段表面上,并通过足够的激波入射点间距和当地顺压强梯度来实现各干扰现象之间的相互隔离。对于目前广泛研究的微型斜坡式涡流发生器,尾迹导致的低能流及其自身诱导的旋涡是其下游流动的两个典型特征。对有限宽度通道内的三维激波/边界层干扰现象,传统的微型斜坡式涡流发生器的控制能力明显不足。为此,本文提出了一种大后掠微型斜坡式涡流发生器,其对通道内激波/边界层干扰现象具有良好的控制能力,其流动控制机理包括预增压效应、分割效应、拦阻效应以及旋涡效应。当激波入射在涡流发生器后半部分时,其控制能力最佳。最后,结合二元高超声速进气道的截短模型,进行了前体激波系调节、唇罩激波/边界层干扰控制等措施的局部记忆合金实现方式研究。结果表明,使用反向变形与多次训练的组合处理方式,可获得具有一定变形量和较高回复速度的记忆合金板。通过专门的记忆合金板与弹簧钢板复合结构,可以有效提其刚度和变形回复速度。以此为基础,设计、加工了一套利用局部记忆合金板变形的高超声速可调进气道模型,并成功完成了各流动控制措施的变形演示。根据纹影实测的轮廓,进行了CFD仿真。结果表明,上述各类流动控制装置能够取得满意的控制效果,并使进气道的总压恢复系数得到明显提升。
[Abstract]:Hypersonic inlet as an important component of supersonic combustion ramjet, affect the performance of the propulsion system. Due to its work in a wide range of Maher number, non design performance is often difficult to balance. Therefore, in order to improve the design / off design performance, need to introduce measures to regulate precursor shock wave and passage shock wave / boundary layer interaction to implement the necessary control. With the continuous development of shape memory alloy materials, the inlet adjustment field show great potential, this paper explores the research on hypersonic inlet flow control methods and key aerodynamic problems. According to the local memory alloy based on hypersonic inlet compression the shock adjustment needs, on the regulation by local change of inlet compression the compression shock, was constructed by the compression bending surface profile The shock wave profile by shock wave contour reverse calculation method of compression surface, and based on the local compression surface bulging effect of external compression shock, puts forward the design principle for bulging shoulder high speed inlet lip expansion ultrasonic wave interference cover of shock wave / boundary layer interaction phenomenon is studied, found in the expansion under the influence of shock wave / wave, the widely used boundary layer interference characteristics of the empirical formula in most cases can not achieve satisfactory results. Further studies show that the expansion wave and cowl shock interaction is a gradual change in the process of its space, there are four different mechanisms, obtained the expansion wave suppression lip cover the favorable range of shock wave / boundary layer interactions. The cowl shock wave / boundary layer interaction phenomenon, put forward the new control method of two-dimensional deformable bulging based on the flow control mechanism And the control law, and the drum used in hypersonic inlet. The research shows that the flow control mechanism mainly includes bulging windward pre compression effect, the convex section of wave dissipation effect and accelerate the expansion fan effect on boundary layer. In the finite width channel, shock wave / boundary layer interaction with 3D feature. The control mechanism of this inhibitory effect also includes bulging diversion effect on the side swept under the low energy flow aggregation phenomenon. Generally, when the shock wave incident on the convex surface of the outer drum of the shock wave / boundary layer interaction has a good control effect. For multi shock wave / boundary layer interaction phenomenon, as the bulge of the control effect the best way, should guarantee the cowl shock were incident on the bulge of the convex surface, and with enough shock incidence point spacing and the local pressure gradient along to realize the isolation between the interference phenomenon. For the present Micro slope of vortex generator, due to its low energy flow wake induced vortex are two typical features of the downstream flow. Three dimensional finite width of shock wave / boundary layer interaction phenomenon in the channel, the traditional slope control of micro vortex generator capacity is obviously insufficient. Therefore, this paper proposes a micro slope type large swept vortex generator, which has high ability to control the channel shock wave / boundary layer interaction phenomenon, the flow control mechanism comprises a pre pressurization effect, segmentation effect, arresting effect and the vortex effect. When the incident shock in the latter part of the vortex generator, its control ability is best. Finally, combined with the truncated model of two yuan hypersonic inlet, a precursor of shock adjustment, study on the implementation of the local memory alloy cowl shock wave / boundary layer interaction control measures. The results show that. With the combination of reverse deformation and multiple training mode, can be obtained with certain memory alloy plate deformation and higher response speed. The memory alloy plate and a spring plate composite structure is special, can effectively improve the stiffness and deformation recovery speed. On the basis of the design, and a set of deformation by using the local memory alloy plate hypersonic variable intake processing model, and the successful completion of the demonstration of the flow deformation control measures. According to the measured schlieren profile, CFD simulation was carried out. The results show that the various flow control devices can achieve good control effect, and make the inlet total pressure recovery coefficient was improved.

【学位授予单位】：南京航空航天大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：V235.21

【相似文献】