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G6135受热负荷零件的温度场测试研究 总被引:4,自引:0,他引:4
过文卿 《柴油机设计与制造》2001,(3):44-47
上海柴油机股份有限公司生产的G6135柴油机在试验考核中,出现第五、六缸拉缸现象。为探究原因,测试人员自行设计,改装设备,运用硬度塞法和热电偶法分别对G6135柴油机活塞和缸套进行温度场测试,这进一步优化和改进零部件设计提供依据。 相似文献
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《小型内燃机与摩托车》1977,(3)
气缸活塞组零件的温度状态是决定发动机有效指标和影响其可靠性及寿命的重要因素之一。有许多研究工作测量过活塞和气缸的温度变化。但是实际上却没有关于拖拉机用柴油机气环的温度状态的资料。参考文献1和2中叙述的活塞环温度测量方法,由于活塞环和活塞之间引线不够耐久,没有得到推广应用。因此,产生了制定比较完善的测量活塞环温度的方法和研制这种装置的必要性,这种方法和装置要保证引线能可靠耐久使用、热电偶引线有可靠的绝缘、热电偶热接点和活塞环有 相似文献
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针对某增压柴油机,使用有限元法研究了内冷油道对活塞温度分布、应力分布和变形分布的影响。为保证边界条件的合理性,通过计算流体力学(CFD)软件模拟计算得到内冷油道的边界条件。采用硬度塞法实测活塞若干点的温度值,验证了模拟计算结果的合理性。有限元计算结果表明:在活塞上加开内冷油道可以使其顶部温度降低约43℃;合理的内冷油道位置可以有效降低局部的高温和应力,当活塞内冷油道位置轴向移动5mm时对活塞顶部温度影响最大,可使其温度变化幅度达10℃左右,最大应力值增加7~11MPa。内冷油道位置的改变主要影响各部分变形的大小,对其分布规律影响不大。 相似文献
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近几年来,热电偶的类型急聚增多,为了避免混乱,合理地进行使用,必须了解它的类型及其使用特性、测量范围等。热电偶通常按术语分为贵金属热电偶、廉金属热电偶、高温或难熔金属热电偶,对于它的使用特性和测量范围等都要根据实际需要测量的温度而定。一般地,测量0~1000℃内的温度,使用中温热电偶,测量1000℃以上的,使用高温热电偶。然而,在电池负极生产中所用电炉(一般为沟槽式感应立式电炉)的使用温度是400~500℃。 相似文献
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采用试验和仿真分析的方法研究了发动机进气冷却作用对汽油机活塞顶温度分布影响.利用硬度塞测温法在发动机台架试验中测量了活塞顶各部位温度,分析比较了活塞顶进气门侧和排气门侧的温度差异.为了考虑冷空气进入气缸时对活塞顶不同部位冷却作用的不同,进行了发动机进气过程流体动力学计算(CFD),得到了进气过程中活塞顶不同部位的换热量,并将其用于修正活塞顶的热边界条件,在此基础上计算了活塞顶的温度分布,并和试验结果进行了对比分析.结果表明:进气冷却作用使得活塞顶进气门侧的温度明显低于排气门侧;利用进气过程CFD分析结果对活塞顶热边界条件进行修正后提高了计算精度,计算结果能够反映活塞顶进、排气门侧的温度差异. 相似文献
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研究了热障涂层厚度对活塞温度、热应力及热变形分布的影响,结合硬度塞法测试无涂层活塞特征点的温度值,采用有限元法与涂层活塞仿真结果进行比较。对不同厚度的涂层进行温度和热应力分析。研究结果表明,在涂层厚度0.3 mm~0.6 mm范围内,厚度每增加0.1 mm,活塞顶面温度提高10℃~17℃,活塞基体温度下降19℃~27℃。与无涂层活塞相比,0.6 mm厚的涂层活塞基体温度最大降幅为10.8%。涂层表面的热应力随着涂层厚度的增加而减小,涂层活塞基体的热应力变化不大。最大热变形处在陶瓷涂层,最大热变形量在活塞与气缸套允许范围之内。 相似文献
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摘要本文采用十五节点等参元和子结构有限元方法在AST-386微型计算机上分析了活塞三维温度场,并利用热电偶测温技术和四连杆引线机构测量了活塞实际温度. 相似文献
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Xiqun Lu Quan Li Wenping Zhang Yibin Guo Tao He Dequan Zou 《Applied Thermal Engineering》2013,50(1):168-176
In this paper, an inverse heat transfer method is employed to conduct thermal numerical analysis on a 4-ring articulated piston of marine diesel engine. The secondary motion of piston and piston ring, and the lubrication oil film has been considered in estimating the coefficient of heat transfer values. Specially manufactured metal plugs were installed in the head of an articulated piston and the piston skirt to measure the temperature distribution of them. A Series of thermal couples were used for cylinder temperature measurement. The boundary condition for numerical simulation is verified with experiment result and applied to predict the temperature distribution of a new piston design which had small change of piston head profile and one less ring scheme. Reasonable agreement was obtained between prediction and experiment for the new design. Experiment result showed increase of temperature in low-temperature area and decrease of maximum value in high-temperature area. The thermal load of the top ring for new piston was lower than old one. The new design had some potential of intensifying improvement from the view point of piston thermal load. 相似文献
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A new method for instantaneous measurement of three thermophysical parameters of solids in situ is proposed. The measurement principle is based on a transient heat conduction model of a thermal probe point contacting a testing body. The measurement of temperature response has been made using the probe of a sheathed K‐type thermocouple in this experiment. Ratios of both thermal conductivity and thermal effusivity between the probe and the testing body are determined from curve‐fitting with the theoretical response to the measured one. As a result, it is shown that the measurement is reproducible and the accuracies of measured thermophysical parameters are good enough to apply this method to many kinds of solids. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(3): 191–201, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10084 相似文献
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对改进的ZH1105W型柴油机缩口四角ω燃烧系统,利用热电偶法实测了标定工况下活塞顶面、侧面和内腔共16个特征点的温度。用Pro/E建立活塞几何模型,选取热结构耦合单元,并对模型网格进行了优化,结合试验值对活塞进行热分析计算,得到活塞三维温度场、热应力场和变形。计算结果表明,在标定工况下,活塞最高温度出现在燃烧室喉部达到310.7℃,最大von Mises热应力出现在排气一侧的回油孔顶部,为68.4 MPa,最大热变形量出现在活塞顶面边缘排气口侧,达到0.328 mm,这为活塞的结构改进和优化提供了依据。 相似文献
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A low cost high temperature test facility designed and built for the purpose of thermo-mechanical testing is described. An induction heater provides variable heating rates, simple operation and easy access for temperature and strain measurement. Specially designed high temperature specimen grips with water-cooling allow for testing over long periods of time. Contact temperature and strain measurements are utilised to provide accurate and reliable results. Detail is given on the experimental procedure including calibration of the thermocouple temperature measurement. A validation study of the thermal expansion and tensile Young’s Modulus of carbon steel 1020 at temperatures up to 850 °C proves the accuracy of the test set-up and procedure. Results are given for the stress–strain curves of aluminium alloy 7000 T4 at various temperatures to further demonstrate the capabilities of the test facility. The measured thermo-mechanical properties of these materials were used to develop high temperature constitutive models for implementation in finite element thermal–structural analysis of hypersonic structures. 相似文献
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活塞环径向压力分布对内燃机的工作性能十分重要,故对其测量的重要性就显而易见.本文分析了几种测量方法,着重介绍了局部薄壁测量法. 相似文献
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用耦合分析法解决内燃机活塞传热问题 总被引:8,自引:0,他引:8
内燃机活塞处于复杂的受热状态:被缸内燃气的瞬时加热和冷却;活塞组与气缸套的动接触传热;冷却油腔及油束的对流换热等。确定上述各部分换热的边界条件成为活塞传热研究的重点和难点。本文采用耦合分析的方法将活塞及与其相互作用的各个部件作为一个整体进行研究,由此确定活塞各边界上的边界条件。并以110型柴油机活塞为实例,应用上述方法确定边界条件,对活塞进行三维有限元计算,计算结果同实验值良好吻合。 相似文献