scholarly journals Modelling and Stability Analysis of Articulated Vehicles

2021 ◽  
Vol 11 (8) ◽  
pp. 3663
Author(s):  
Tianlong Lei ◽  
Jixin Wang ◽  
Zongwei Yao
Keyword(s):  
Stability Analysis ◽  
Critical Velocity ◽  
Equations Of State ◽  
Steering System ◽  
Analysis Model ◽  
Nonlinear Dynamic Model ◽  
Equilibrium Equations ◽  
Eigenvalue Method ◽  
Articulated Vehicles ◽  
The Stability

This study constructs a nonlinear dynamic model of articulated vehicles and a model of hydraulic steering system. The equations of state required for nonlinear vehicle dynamics models, stability analysis models, and corresponding eigenvalue analysis are obtained by constructing Newtonian mechanical equilibrium equations. The objective and subjective causes of the snake oscillation and relevant indicators for evaluating snake instability are analysed using several vehicle state parameters. The influencing factors of vehicle stability and specific action mechanism of the corresponding factors are analysed by combining the eigenvalue method with multiple vehicle state parameters. The centre of mass position and hydraulic system have a more substantial influence on the stability of vehicles than the other parameters. Vehicles can be in a complex state of snaking and deviating. Different eigenvalues have varying effects on different forms of instability. The critical velocity of the linear stability analysis model obtained through the eigenvalue method is relatively lower than the critical velocity of the nonlinear model.

Dynamic Stability Analysis of the Tower Structure of Construction Elevators

2013 ◽  
Vol 459 ◽  
pp. 646-649
Author(s):  
Xian Rong Qin ◽  
Ying Hong ◽  
Peng Yue ◽  
Qing Zhang ◽  
Yuan Tao Sun
Keyword(s):  
Stability Analysis ◽  
Stress Field ◽  
Dynamic Stability ◽  
Transient Analysis ◽  
Stress Effect ◽  
Construction Process ◽  
Moving Loads ◽  
Eigenvalue Method ◽  
Tower Structure ◽  
The Stability

This paper proposed a method of dynamic stability analysis for the tower structure of construction elevators based on dynamic eigenvalue method. The method employed the time frozen formulation to model the problem, and the stress field from transient analysis was utilized to simulate the pre-stress effect of buckling analysis. The proposed method was applied to estimate the dynamic stability of the tower structure of construction elevators under moving loads, and the results suggest that high coefficients of lateral load and inclined tower structure will dramatically reduce the stability of the elevator in the construction process.

Stability Bearing Capacity of Dendritic Arms in Tainter Gate

2015 ◽  
Vol 733 ◽  
pp. 464-467
Author(s):  
Yong Kang Shen ◽  
Zheng Zhong Wang ◽  
Chun Long Zhao
Keyword(s):  
Stability Analysis ◽  
Bearing Capacity ◽  
Effective Length ◽  
Analysis Method ◽  
Analysis Model ◽  
Minimum Potential Energy ◽  
Stability Bearing Capacity ◽  
Minimum Potential ◽  
The Stability ◽  
Radial Gate

The new arms form of radial gate—dendritic arms is introduced for the proper mechanical mechanism, however the stability design is very difficult. According to the stability theory of structure, the stability analysis model of step column with lateral restraints was proposed for dendritic arms, some equations was derived from the principle of minimum potential energy, the practical formulas of buckling bearing capacity and effective length coefficient were provided. According to an example, the accuracy on formulas was verified by finite analysis method.

Flash Calculation Using Successive Substitution Accelerated by the General Dominant Eigenvalue Method in Reduced-Variable Space: Comparison and New Insights

SPE Journal ◽  
2020 ◽  
Vol 25 (06) ◽  
pp. 3332-3348
Author(s):  
Haining Zhao ◽  
Hongbin Jing ◽  
Zhengbao Fang ◽  
Hongwei Yu
Keyword(s):  
Stability Analysis ◽  
Phase Stability ◽  
Linear Acceleration ◽  
Phase Region ◽  
Dominant Eigenvalue ◽  
Two Phase ◽  
Eigenvalue Method ◽  
Successive Substitution ◽  
The Stability ◽  
Flash Calculation

Summary On the basis of a previously published reduced-variables method, we demonstrate that using these reduced variables can substantially accelerate the conventional successive-substitution iterations in solving two-phase flash (TPF) problems. By applying the general dominant eigenvalue method (GDEM) to the successive-substitution iterations in terms of the reduced variables, we obtained a highly efficient solution for the TPF problem. We refer to this solution as Reduced-GDEM. The Reduced-GDEM algorithm is then extensively compared with more than 10 linear-acceleration and Newton-Raphson (NR)-type algorithms. The initial equilibrium ratio for flash calculation is generated from reliable phase-stability analysis (PSA). We propose a series of indicators to interpret the PSA results. Two new insights were obtained from the speed comparison among various algorithms and the PSA. First, the speed and robustness of the Reduced-GDEM algorithm are of the same level as that of the reduced-variables NR flash algorithm, which has previously been proved to be the fastest flash algorithm. Second, two-side phase-stability-analysis results indicate that the conventional successive-substitution phase-stability algorithm is time consuming (but robust) at pressures and temperatures near the stability-test limit locus in the single-phase region and near the spinodal in the two-phase region.

Stability Analysis Model of Eco Economic System based on Discrete Selection

2021 ◽  
Vol 7 (6) ◽  
pp. 6375-6387
Author(s):  
Yijing Wang
Keyword(s):  
Stability Analysis ◽  
Economic System ◽  
Resource Utilization ◽  
Evaluation System ◽  
System Analysis ◽  
Selection Model ◽  
Net Income ◽  
Analysis Model ◽  
Comprehensive Development ◽  
The Stability

The internal structure of eco-economic system is relatively complex, and its stability is easily affected by external environmental factors such as region, which results in poor accuracy of die results of its analysis. Based on this, the stability analysis model of eco-economic system based on discrete selection is proposed. In order to improve the accuracy of eco-economic system analysis, the characteristics of discrete selection model are analyzed. Based on the principles of scientificity, practicability, regionality, operability and dynamic, and the comprehensive development of four sub-systems of economy, land, environment and society, the indexes of economy, land, environment and society are selected to build the stability evaluation of eco-economic system Price index system: through adjusting the structure of resource utilization, the indexes are selected hierarchically to truly reflect the structure of resource utilization. The weight of each index is obtained by AHP, and the component of each index in the evaluation system is reasonably divided. According to the theory of stochastic utility, the elements of discrete selection model are analyzed, and then the discrete selection model is constructed. By studying the close degree of each evaluation object and ideal solution, the stability analysis of ecological economic system is realized. The experimental results show that the influence of the proposed model on net income per unit is relatively stable at the positive and negative balance points, which is consistent with the actual situation., and the shortest analysis time is 1.2 min, which is feasible.

Stability Analysis Model of a Quadruped Walking Machine at Walking up a Step

2013 ◽  
Vol 284-287 ◽  
pp. 950-957
Author(s):  
Yu Gang Chen ◽  
Jo Peng Tsai
Keyword(s):  
Stability Analysis ◽  
Analysis Model ◽  
Ancient China ◽  
Walking Machine ◽  
Walking Gait ◽  
Uneven Terrain ◽  
The Stability

According to the documents, an ancient Chinese carpenter named Lu Ban invented a four-legged wooden horse carriage in the Chou Dynasty in ancient China, around 480 B.C. This wooden horse carriage could simulate the walking gait of a horse very well but it needed a carriage to keep balance while walking. This paper proposes a method of stability analysis model for the locomotion of a quadruped wooden horse without the support of a carriage. First of all, four most unstable conditions are constructed based on the gait theory of the quadruped wooden horse. The stability areas are obtained by taking the intersections of supporting boundaries that are constructed under various unstable conditions for walking on even and uneven terrain. These results of the stability analysis model are useful for supervising the stability of locomotion of a quadruped.

scholarly journals The Evaluation Method of Rock Mass Stability Based on Natural Frequency

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Mowen Xie ◽  
Weinan Liu ◽  
Yan Du ◽  
Qingbo Li ◽  
Hongfei Wang
Keyword(s):  
Stability Analysis ◽  
Natural Frequency ◽  
Evaluation Method ◽  
Limit Equilibrium ◽  
Three Dimensional ◽  
Analysis Model ◽  
Stability Calculation ◽  
Rock Stability ◽  
Site Monitoring ◽  
The Stability

The limit equilibrium method’s analysis index cannot be measured by on-site monitoring equipment and cannot be used for monitoring and early warning of rock instability. The existing rock stability evaluation methods based on vibration information cannot evaluate the stability of rocks quantitatively. In this paper, the slope’s constraints on the rock were simplified to springs and a three-dimensional analysis model of rock vibration was established. The equation for calculating the natural frequency of rock that includes the spring stiffness as an indicator was derived. The rock stability calculation function containing the index of natural frequency was brought into the traditional rock stability coefficient calculation equation, and a new rock stability analysis method based on natural frequency was established. The experiment proved the measurability of the index of the natural frequency of rock and the method’s effectiveness for the stability analysis of the rock based on natural frequency.

Stability Analysis of the Nanjung Water Diversion Twin Tunnels based on Convergence Measurement

2019 ◽  
Vol 1 (1) ◽  
pp. 49-60
Author(s):  
Simon Heru Prassetyo ◽  
Ganda Marihot Simangunsong ◽  
Ridho Kresna Wattimena ◽  
Made Astawa Rai ◽  
Irwandy Arif ◽  
...  
Keyword(s):  
Stability Analysis ◽  
Convergence Rate ◽  
Critical Strain ◽  
Convergence Rates ◽  
Strain Analysis ◽  
Water Diversion ◽  
Tunnel Face ◽  
Tunnel Stability ◽  
The Stability ◽  
Twin Tunnels

This paper focuses on the stability analysis of the Nanjung Water Diversion Twin Tunnels using convergence measurement. The Nanjung Tunnel is horseshoe-shaped in cross-section, 10.2 m x 9.2 m in dimension, and 230 m in length. The location of the tunnel is in Curug Jompong, Margaasih Subdistrict, Bandung. Convergence monitoring was done for 144 days between February 18 and July 11, 2019. The results of the convergence measurement were recorded and plotted into the curves of convergence vs. day and convergence vs. distance from tunnel face. From these plots, the continuity of the convergence and the convergence rate in the tunnel roof and wall were then analyzed. The convergence rates from each tunnel were also compared to empirical values to determine the level of tunnel stability. In general, the trend of convergence rate shows that the Nanjung Tunnel is stable without any indication of instability. Although there was a spike in the convergence rate at several STA in the measured span, that spike was not replicated by the convergence rate in the other measured spans and it was not continuous. The stability of the Nanjung Tunnel is also confirmed from the critical strain analysis, in which most of the STA measured have strain magnitudes located below the critical strain line and are less than 1%.

Sign in / Sign up

Export Citation Format

Share Document