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针对面向性能的发动机冷却风扇叶片几何形状优化的问题,将参数化建模技术应用到对冷却风扇叶片安装角的描述中,建立了冷却风扇的参数化模型,以多学科优化平台Isight和商业流体模拟软件Fluent为基础,建立了一种模型参数化、网格划分、CFD分析和多目标优化相结合的发动机冷却风扇优化集成平台,并运用非支配排序遗传算法对冷却风扇进行了优化。对优化结果与试验结果进行了对比,分析了冷却风扇的内部流场。研究结果表明,优化后的风扇模型静压提高了12.840 6%,动压和风扇效率也有所提高,冷却风扇的整体性能得到了优化。 相似文献
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《机械科学与技术》2016,(5):815-820
根据齿轮驱动风扇构型的航空发动机试验时风扇驱动齿轮箱试验件各滑油喷嘴精确供油要求,在液压加载式功率流封闭齿轮试验台供油路上加装了一个可以多路变压力分油的分油装置,分油装置内腔设计多条油路支路,在支路上安装有节流元件,通过调节节流内孔孔径和长度控制节流元件压降,向试验齿轮箱各滑油喷嘴提供多路不同压力的滑油,使得试验齿轮箱滑油喷嘴流量和流速精确达到试验要求。采用Flowmaster软件对试验台滑油供油系统进行了一维稳态仿真分析,分析了节流元件内孔长度和孔径对试验齿轮箱滑油喷嘴流量和流速的影响作用。结果表明:节流内孔孔径对节流元件压降的影响远大于节流内孔长度对节流元件压降的影响,特别是当节流内孔孔径在1 mm至3 mm之间时,节流元件对滑油供油流路压力具有明显的调节作用。 相似文献
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发动机冷却风扇在工作过程中,由于叶片表面压力存在一定的结构变形会对风扇的气动性能产生影响,尤其对大尺寸、高负荷风扇的影响更大。基于Ansys Workbench软件,采用双向流固耦合方法对某型号发动机用冷却风扇的气动性能进行了计算分析,并将其结果和不考虑风扇变形的CFD方法得到的风扇气动性能结果与试验值进行了对比。结果表明:考虑了风扇变形因素的双向流固耦合仿真得到的结果更接近于试验值;采用双向流固耦合方法对风扇气动性能进行计算,可显著降低计算值与试验值的偏差。 相似文献
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以不削弱气动性能为前提,为提高发动机冷却风扇的噪声性能,以计算流体力学(CFD)与计算气动声学(CAA)理论为基础求解冷却风扇的气动性能和噪声性能,并与气动性能试验噪声试验结果进行对比验证了该计算方法的可靠性。对原模型的平面叶型进行优化,得到最低噪声参数组合,经CFD/CAA联合仿真验证,优化后风扇模型的气动性能与噪声性能均得到改善,从流场与声场分布的角度对优化前后的冷却风扇进行详细的对比,进一步地分析优化前后冷却风扇气动性能和噪声性能变化的机理,深入地研究其叶片结构参数对冷却风扇性能的影响机理。 相似文献
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本文对进气部件结构形式对局扇的噪声及空气动力性能进行了试验研究,并提出了改进设计方案。结果表明,设计结构合理的局扇进口部件不但可以提高局扇的空气动力性能而且可以明显地降低局扇的噪声 相似文献
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Measurements have been made in an automotive HVAC blower for two different centrifugal fans. This work is directed at improving the performance of a conventional forward-curved centrifugal fan for a given small blower casing. Mean velocities and pressure have been measured using a miniature five-hole probe and a pressure scanning unit connected to an online data acquisition system. First, we obtained the fan performance curves versus flow rates showing a significant attenuation of unstable nature achieved with the new fan rotor in the surging operation range. Second, aerodynamic characterizations were carried out by investigating the velocity and pressure fields in the casing flow passage for different fan operating conditions. The measurements showed that performance coefficients are strongly influenced by flow characteristics at the throat region. The main flow features were common in both fans, but improved performance is achieved with the new fan rotor, particularly in lower flow rate regions. Based on the measured results, design improvements were carried out in an acceptable operation range, which gave considerable insight into what features of flow behavior were most important. 相似文献
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Planetary gear set is the critical component in helicopter transmission train,and an important problem in condition monitoring and health management of planetary gear set is quantitative damage detection.In order to resolve this problem,an approach based on physical models is presented to detect damage quantitatively in planetary gear set.A particular emphasis is put on a feature generation and selection method,which is used for sun gear tooth breakage damage detection quantitatively in planetary gear box of helicopter transmission system.In this feature generation procedure,the pure torsional dynamical models of 2K-H planetary gear set is established for healthy case and sun gear tooth-breakage case.Then,a feature based on the spectrum of simulation signals of the dynamical models is generated.Aiming at selecting the best feature suitable for quantitative damage detection,a two-sample Z-test procedure is used to analyze the performance of features on damage evolution tracing.A feature named SR,which had better performance in tracking damage,is proposed to detect damage in planetary gear set.Meanwhile,the sun gear tooth-chipped seeded experiments with different severity are designed to validate the method above,and then the test vibration signal is picked up and used for damage detection.With the results of several experiments for quantitative damage detection,the feasibility and the effect of this approach are verified.The proposed method can supply an effective tool for degradation state identification in condition monitoring and health management of helicopter transmission system. 相似文献
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影响齿轮箱噪声的因素及其控制方法 总被引:2,自引:0,他引:2
噪声是评价齿轮装置性能的一项重要指标。降低噪声是齿轮箱设计要考虑的主要内容。根据多年从事齿轮箱设计工作的经验,论述影响齿轮箱噪声的因素以及控制与降低噪声的方法。 相似文献
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对通风机应用中的选型设计常见通病进行了分析;介绍了前苏联试验研究输气载尘对通风机性能的影响;对引进英国的高温风机载尘的节能效果进行了验证及应用分析;简介了日本老厂改造低效集尘风机的节能效果。评述了引风机高温载尘进气条件下的不节能的若干问题。提出了选型设计的节能原则,使用风机的节能措施。 相似文献
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This paper presents the mean streamline analysis using the empirical loss correlations for performance prediction of cross-flow
fans. Comparison of overall performance predictions with test data of a cross-flow fan system with a simplified vortex wall
scroll casing and with the published experimental characteristics for a cross-flow fan has been carried out to demonstrate
the accuracy of the proposed method. Predicted performance curves by the present mean streamline analysis agree well with
experimental data for two different cross-flow fans over the normal operating conditions. The prediction method presented
herein can be used efficiently as a tool for the preliminary design and performance analysis of general-purpose cross-flow
fans. 相似文献