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41.
三轴汽车前后轮角输入时的响应特性 总被引:5,自引:0,他引:5
本文详细推导了三轴汽车线性二自由度模型的运动微分方程,分析了汽车对前后轮角输入时的移居记响应特性。从汽车动力学的角度讨论了前后轮转应具备的比例关系。该方法同样适用于其它多轴汽车的建模分析。 相似文献
42.
在轮胎静生趣特怀建模的基础上,探讨了利用轮胎模态参数对轮胎纯侧偏特性的建模。通过侧向激振试验提取了轮胎的侧向模态参数并计算了轮胎在不同载荷下的偏离特性,计算结果与以往轮胎的试验结果具有很好的一致性。计算结果转化为无量纲形式并与经验模型进行了比较,建模和计算结果充分说明了模型的合理并显示了建模方法的优越性。 相似文献
43.
应用水平定向钻安装管道时回拖拉力的计算方法 总被引:1,自引:2,他引:1
研究了应用水平定向钻机安装地下管道回拖过程中的受力特征,分析了计算回拖拉力时参数的选择以及公式应用的特点,并将预测数据与实验数据作了对比分析,从而得出了回拖拉力与孔道直径成反比. 相似文献
44.
45.
选定粤赣高速公路有代表性的6种岩层,对其全、强、弱风化层组成的路堑高边坡锚索加固工程进行了69次破坏性拉拔试验。试验中对每种不同风化程度的岩(土)层采用锚固长度为1m、2m、3m的现场拉拔试验,计算出锚索加固边坡的锚固力值,为验证高边坡工程设计提供了准确的力学参数,也为全线高边坡工程的施工工艺提供指导性意见。同时,节省了大量的试验费用和时间,获得了显著的经济效益。 相似文献
46.
Transfer functions are often used together with a wave spectrum for analysis of wave–ship interactions, where one application addresses the prediction of wave-induced motions or other types of global responses. This paper presents a simple and practical method which can be used to tune the transfer function of such responses to facilitate improved prediction capability. The input to the method consists of a measured response, i.e. time series sequences from a given sensor, the 2D wave spectrum characterising the seaway in which the measurements are taken, and an initial estimate of the transfer function for the response in study. The paper presents results obtained using data from an in-service container ship. The 2D wave spectra are taken from the ERA5 database, while the transfer function is computed by a simple closed-form expression. The paper shows that the application of the tuned transfer function leads to predictions which are significantly improved compared to using the transfer function without tuning. 相似文献
47.
结合某国道滑坡情况,根据其具体的工程地质和水文情况,提出了采用抗滑桩的处理方案。根据滑坡推力计算,确定抗滑桩的尺寸及位置,提出了施工过程动态监测和完工后长期监测的方案。 相似文献
48.
基于滑移网格方法,采用SST k-ω湍流模型研究不同网格划分方式对带前置定子导管式推进器非定常性能的研究。首先基于相对参考坐标系法及滑移网格方法分别对推进器在定常与非定常下的性能进行数值预报,并与试验结果相比验证计算方法的可靠性。基于该方法研究整体网格划分方式与周期性网格对推力系数、扭矩系数与推进器各个方向上的非定常脉动力的影响。研究结果为进一步研究推进器非定常性能提供了参考。 相似文献
49.
The response of an offshore wind turbine tower and its monopile foundation has been investigated when exposed to linear and fully nonlinear irregular waves on four different water depths. The investigation focuses on the consequences of including full nonlinearity in the wave kinematics. The linear and nonlinear irregular wave realizations are calculated using the fully nonlinear potential flow wave model OceanWave3D [1]. The linear and nonlinear wave realizations are compared using both a static analysis on a fixed monopile and dynamic calculations with the aeroelastic code Flex5 [2]. The conclusion from this analysis is that linear wave theory is generally sufficient for estimating the fatigue loading, but wave nonlinearity is important in determining the ultimate design loads. 相似文献
50.
In this study, Submerged Floating Tunnel (SFT)-mooring-train coupled dynamics is solved in the time domain to investigate their dynamic and hydro-elastic interactions under wave and earthquake excitations. The SFT is modeled by the rod-FE (finite element) theory, and it is connected to mooring lines through dummy-connection-mass and linear and rotational springs. A 3D rigid-multi-body dynamic model is developed for train dynamics that consists of seven rigid bodies. The tunnel-train interaction is taken into consideration based on the wheel-rail correspondence assumption and the simplified Kalker linear creep theory. The developed computer simulation program is validated through comparisons with commercial programs and published results when possible. In the case of earthquake-induced dynamics of the coupled system, the effects of soil conditions, tunnel length, mooring interval, seismic-wave propagation, and seaquake are investigated. The magnitudes of the SFT downward motions induced by the moving train are small compared with the motions induced by earthquakes. The earthquake causes transient SFT responses especially at their lowest wet natural frequencies while high-frequency motions are induced by seaquake effect. Structural damping and seismic propagation play an important role in dynamic responses. The interaction of the tunnel and moving train is also evaluated for various train speeds in terms of the derailment and offload factors and riding-comfort criterion. For the given SFT and train designs, the offload factor and riding-comfort criterion can slightly exceed their limits at certain earthquake conditions with the speed as high as 70 m/s, which can be adjusted by reducing train speed. 相似文献