【作者】 宫春梅；

【导师】 李宇鹏；

【作者基本信息】 燕山大学 ， 机械制造及其自动化， 2012， 硕士

【摘要】 在设计制造领域，任何产品的问世都蕴含着对已有科学技术的应用和借鉴，叶片作为散热、冷却和能量转换的关键部件，其内部流场的流动状况直接影响到整机的性能。因此，研究现有叶片技术是改进和开发高性能叶片产品的重要途径和有效手段。叶片表面为复杂的空间曲面，经调研发现关于叶片截面几何参数的详尽资料公布的相对较少。那么如何快速、有效的消化吸收实际应用叶片的关键技术，完成叶片类产品的高性能设计，成为现阶段各领域亟待解决的问题。逆向工程是消化吸收先进技术、实现产品快速创新设计的重要手段，实物原型的再现仅仅是逆向工程的初级阶段，利用CAD/CAE/CAM技术实现产品的创新设计才是逆向工程的真正目的和最终目标。本文以汽车冷却风扇叶片为研究对象，近年来由于排气净化、车内冷气设备的普及和车头设计迎风面积的逐渐减小，发动机热负荷越来越高，导致原有冷却风扇不易保证完成较高热负荷下的冷却工作。通过逆向工程技术获取实物表面数字化模型、结合动量-叶素理论分析叶片几何参数对风扇性能的影响规律，运用CFD方法对风扇内部流场进行仿真，计算结果表明叶片表面的气压分布不均、静压值偏低、风道尾部出现速度回流，这些不仅降低风扇冷却效率，也增大了发动机功率消耗。因此，为改善汽车冷却风扇性能，对叶片进行改型设计有其必要性和可行性。通过以上研究工作的开展，将叶片截面曲线设计为椭圆线，得到改型后的叶片曲线形式更加规范，便于叶片的加工；在性能上提高了风扇的冷却效率，减少了功率消耗，也为通风设备中关键零件叶片的设计和生产提供了有利参考。更多还原

【Abstract】 In the design and manufacture field, any product comes out which contains referenceof existing science and technology. Blade is a key component of cooling and energytransition, its internal fluid conditions directly affect machine performance, therefore,there is an effective measure and important approach based on existing blade technologyto improve and develop blade product performance.Blade with complex space surface, after survey and research on information or dataof blade sectional curve found that there are published very little. So how to quickly andefficiently absorb key technology of blade in actual application, complete highperformance design of blade product is an urgent problem to be solved in many filed.Reverse engineering is an important approach to digest and absorb advanced technology,and the prototype of reproduction is the primary stage, the use of CAD/CAE/CAMtechnology to realize product innovation design is the true purpose and ultimate goal.In this paper, taking car cooling fan as object, duo to exhaust purification, aircondition popularization and weather area reduction of automobile body in recent years,heat loading of engine is increasing gradually, resulting in existing cooling fan can notguarantee much higher cooling work. Through reverse engineering technology to acquirefan digital model, based on momentum-blade element theory to analyse relation betweengeometric parameters and aerodynamics characteristic, utilize CFD method to simulate faninternal fluid, conclusions show that pressure distribution of the blade surface isnonuniform and speed turns out vortex, which not only reduce fan cooling efficiency, butstill increase the engine power consumption. Therefore, it is necessary and feasible toestablish a remodel blade in order to improve automotive cooling fan performance.Through the above research, put forward elliptical curve replace with original bladeprofile curve, then get a remodelled blade curve of standardization. It is not onlyconvenient for manufacturing, but achieving higher cooling efficiency and reducingenergy power consumption of automobile fan, providing a practical reference value forkey parts design and production of ventilation equipment.更多还原