Study on control of air suspension system for railway vehicle to prevent wheel load reduction at low-speed transition curve negotiation

2006 ◽  
Vol 44 (sup1) ◽  
pp. 814-822 ◽  
Author(s):  
Y. Suda ◽  
W. Wang ◽  
H. Komine ◽  
Y. Sato ◽  
T. Nakai ◽  
...  
Author(s):  
Yoshihiro Suda ◽  
Wenjun Wang ◽  
Hisanao Komine ◽  
Yoshi Sato ◽  
Takuji Nakai ◽  
...  

This paper presents the curving performance of railway vehicles with Air Suspensions. Air Suspensions sometimes cause reduction of Wheel Load at transition curve negotiation. The axle spring of leading axle outside and air spring of leading bogie outside will extend when passing the exit transition curve because of the distortion of the track plane. Because Air Suspension has an automatic leveling function that each air spring is controlled by Leveling Valve to maintain a constant length, air in the extended spring exhaust through Leveling Valve to reduce the pressure of this air spring in order to make it back to original length. So the air spring pressure of leading bogie outside reduces furthermore and Wheel Load of leading axle outside reduces severely. This may be the reason of derailment. The distortion of track plane unbalances inner pressure of Air Suspensions and vertical load of wheels at entrance transition curve, because of the nonlinear characteristic of Air Suspension system caused by the Leveling Valve. Computer simulation of low speed transition curve negotiation shows that the lower running speed is, the more severe unbalance of Air Suspension inner pressure and Wheel Load become. The reduction of 1st axle outside wheel at exit transition curve is depended on this Wheel Load unbalance phenomena at circular curve. And this running process influences the after behavior of railway vehicle. The simulation also shows that the longer entrance transition curve is, the more severely the 1st axle outside Wheel Load reduces. The full-scale bench experiments gave the result as nearly same as computer simulation. A new concept control device is proposed to prevent the reduction of Wheel Load at exit transition curve. Both the simulation and bench experiment proved its control performance of Wheel Load reduction prevention. And proposed control device can also be used in tilting control and kneeling control of railway vehicle. General multi-body dynamics analysis software SIMPACK is used to confirm advantageous effect of proposed control device and full vehicle curve passing simulation shows that derailment coefficient reduced when proposed control device is applied in transition curve negotiation.


Author(s):  
Takayuki Tanaka ◽  
Hiroyuki Sugiyama

Abstract Accurate prediction of vehicle curve negotiation performance is critically important for evaluation of railway vehicle safety. Although multibody dynamics vehicle simulation has been widely utilized for the vehicle performance evaluation, nonlinearities associated with the air suspension behavior are vastly simplified and the air mass flows of the leveling valve (LV) and differential pressure valve (DPV) are neglected in many cases. It is, however, known that changes in the air spring pressure caused by the LV and DPV make a non-negligible impact on the vertical wheel load variation and the derailment safety in small radius curved tracks. Therefore, this paper presents a numerical procedure for the analysis of the coupled vehicle and air suspension system behavior, considering nonlinearities associated with LV and DPV flow characteristics. To enable quick and accurate prediction of the history-dependent LV-induced wheel load unbalance and its impact on the derailment safety, quasi-static vehicle motion solvers for the fully coupled vehicle and air spring system flow equations are developed. Several numerical examples are presented to demonstrate the simulation capabilities developed in this study and numerical results are validated against the test data.


Transport ◽  
2016 ◽  
Vol 33 (1) ◽  
pp. 291-301 ◽  
Author(s):  
Peng-Fei Liu ◽  
Wan-Ming Zhai ◽  
Kai-Yun Wang ◽  
Quan-Bao Feng ◽  
Zai-Gang Chen

This paper presents a method to study the vertical dynamic characteristics of a heavy-haul locomotive in curve. A quasi-static analysis model based on the static force equilibrium relationship is established to investigate the load bearing characteristics of suspension system when the locomotive runs through the curve. Then a locomotive–track coupled dynamics model is used to analyse the dynamic characteristics of wheel load in curves. Finally, a field test in curve is carried out to validate the simulated results. The theoretical analysis results indicate that due to the different twist shapes of track on the entry and exit transition curves, for some specific position in the suspension system or wheel arrangements, the corresponding vertical load along the curve length presents an asymmetry about the section of circular curve. The asymmetry is predominantly caused by the Superelevation Angle Differences (SADs) between car body, bogie frames and wheelsets. A distinct phenomenon is that the outer wheel–rail vertical load of the first axle increases when the locomotive enters the transition curve and then reduces when it exits. These results are expected to provide theoretical guidance to the design of the heavy-haul railways. It is suggested that the asymmetric characteristics of the wheel loads can be improved by some measures, such as adopting a low vertical stiffness in the secondary suspension and increasing the transition curve length.


Actuators ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 12
Author(s):  
Dang Viet Ha ◽  
Vu Van Tan ◽  
Vu Thanh Niem ◽  
Olivier Sename

The air suspension system has become more and more popular in heavy vehicles and buses to improve ride comfort and road holding. This paper focuses on the evaluation of the dynamic load reduction at all axles of a semi-trailer with an air suspension system, in comparison with the one using a leaf spring suspension system on variable speed and road types. First, a full vertical dynamic model is proposed for a tractor semi-trailer (full model) with two types of suspension systems (leaf spring and air spring) for three axles at the semi-trailer, while the tractor’s axles use leaf spring suspension systems. The air suspension systems are built based on the GENSYS model; meanwhile, the remaining structural parameters are considered equally. The full model has been validated by experimental results, and closely follows the dynamical characteristics of the real tractor semi-trailer, with the percent error of the highest value being 6.23% and Pearson correlation coefficient being higher than 0.8, corresponding to different speeds. The survey results showed that the semi-trailer with the air suspension system can reduce the dynamic load of the entire field of speed from 20 to 100 km/h, given random road types from A to F according to the ISO 8608:2016 standard. The dynamic load coefficient (DLC) with the semi-trailer using the air spring suspension system can be reduced on average from 14.8% to 29.3%, in comparison with the semi-trailer using the leaf spring suspension system.


Author(s):  
Takayuki Tanaka ◽  
Hiroyuki Sugiyama

While air suspensions are widely utilized for passenger railway vehicles as secondary suspension, initial lever angle setting of the air spring levelling valve can make a non-negligible impact on the residual wheel load unbalance in curve negotiation on small radius curved tracks. To enable accurate and quick prediction of the levelling valve-induced residual wheel load unbalance for vehicle safety evaluation, this study proposes a new quasi-steady curve negotiation analysis procedure considering the detailed thermodynamic air suspension system model that accounts for the nonlinear airflow characteristics of levelling valve and differential pressure valves. This approach allows for eliminating a limitation of existing full dynamic simulation models associated with high computational intensity that prevents quick safety evaluation with long-distance simulation under actual railway operating scenarios. A co-simulation scheme for the quasi-steady vehicle motion solver is also proposed to further improve the computational efficiency with explicit force–displacement coupling. Several numerical examples are presented to demonstrate the proposed quasi-steady vehicle motion solver for prediction of levelling valve-induced residual wheel load unbalances in small radius curved tracks. The numerical results are compared with those of the dynamic simulation model and validated against the test data. It is demonstrated that computational time is substantially decreased by the proposed approach while accurately predicting the levelling valve-induced residual wheel load unbalance caused by the initial offset of lever angles on small radius curved tracks.


Author(s):  
Toshihisa Nakajima ◽  
Yoshiyuki Shimokawa ◽  
Masaaki Mizuno ◽  
Hiroyuki Sugiyama

In this investigation, a nonlinear air suspension system model that accounts for the coupling between air springs, leveling valves, and differential pressure valves is developed and integrated into general-purpose multibody dynamics computer algorithms. It is demonstrated that the proposed model can capture highly nonlinear air suspension characteristics resulting from the coupling with leveling and differential pressure valves, and good agreements are obtained between the numerical and on-track test results. Furthermore, the effect of flow characteristics of leveling valves on the wheel load unbalance on spiral curve sections is discussed. The numerical results obtained by the proposed model clearly indicate the importance of modeling the nonlinear flow characteristics of the leveling and differential pressure valves for assessing the vehicle safety in low speed operations on a small radius curved track.


Author(s):  
Premandanda Pradhan ◽  
Dharmendra Singh

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