Applicability of the Vortex Methods for Aerodynamics of Heavy Vehicles

Author(s):  
Kyoji Kamemoto ◽  
Akira OJima
Entropy ◽  
2021 ◽  
Vol 23 (1) ◽  
pp. 118
Author(s):  
Kseniia Kuzmina ◽  
Ilia Marchevsky ◽  
Irina Soldatova ◽  
Yulia Izmailova

The possibilities of applying the pure Lagrangian vortex methods of computational fluid dynamics to viscous incompressible flow simulations are considered in relation to various problem formulations. The modification of vortex methods—the Viscous Vortex Domain method—is used which is implemented in the VM2D code developed by the authors. Problems of flow simulation around airfoils with different shapes at various Reynolds numbers are considered: the Blasius problem, the flow around circular cylinders at different Reynolds numbers, the flow around a wing airfoil at the Reynolds numbers 104 and 105, the flow around two closely spaced circular cylinders and the flow around rectangular airfoils with a different chord to the thickness ratio. In addition, the problem of the internal flow modeling in the channel with a backward-facing step is considered. To store the results of the calculations, the POD technique is used, which, in addition, allows one to investigate the structure of the flow and obtain some additional information about the properties of flow regimes.


2015 ◽  
Vol 743 ◽  
pp. 526-532 ◽  
Author(s):  
C.M. Jiang ◽  
J.J. Lu ◽  
L.J. Lu

Based on the originally unprocessed data from the Official Platform of“110”Alarming Receiving Center (OP110ARC) of Shanghai Public Security Bureau (SPSB), 529 single-vehicle crashes reported during one year and a half which happened at the thirteen urban road tunnels going across the Huangpu River are used in this study. To investigate the factors affecting the crash influence severity levels, ordered probit regression is established. Several categories of factors are considered as explanatory variables in the models. The study finds that the entrance of the tunnels is the site where severe injury crashes trend to occur. Rainy and snowy days impose vehicles and motorists driving via the tunnel sections in danger. Tunnels with a low speed limit (40 km/h in this study) may be not as safe as we thought before. Two-wheel vehicles without sufficient physical protection for its drivers and heavy vehicles also show a negative effect on the operation safety of single-vehicle at these studied tunnels. Alcohol involved drivers are more likely to suffer from a severe crashes and gets badly hurt.


1978 ◽  
Vol 32 (143) ◽  
pp. 791 ◽  
Author(s):  
Ole Hald ◽  
Vincenza Mauceri Del Prete

2016 ◽  
Vol 54 (11) ◽  
pp. 1601-1628 ◽  
Author(s):  
Graeme Morrison ◽  
David Cebon

Author(s):  
Tina Mirfakhraie ◽  
Ramiro Liscano ◽  
Shenjin Zhu ◽  
Yuping He

This paper presents an active trailer steering (ATS) system using a wireless communication link to facilitate exchanging information among vehicle units of articulated heavy vehicles (AHVs). A challenge for developing and implementing the wireless-communication-based ATS system is to address the problems of delay and packet-loss. Embedding wireless communication transceivers on an AHV may introduce delays for data exchange, and the transmitted data may be lost. Many reasons may lead to the delay and packet-loss, e.g., channel fading, noise burst, interference, etc. The proposed ATS system may prevent unstable motion modes of AHVs if the sensor data reach the controllers/actuators in real-time with an acceptable level of delay and packet-loss. In order to ensure the performance of the ATS control, a Kalman-filter-based estimator is introduced. The estimator uses the available dynamic data to estimate the current states of the AHV in case some sensor information is not available due to a delay or an outage in the wireless communication link. To investigate the effect of the time delay due to the wireless communication on the performance of the ATS control, co-simulations are conducted. The wireless network is modeled using TrueTime toolbox, the ATS controller is designed in SimuLink package, and the AHV model is constructed in TruckSim software. Integrating the wireless network modeled in TrueTime, the ATS controller designed in SimuLink, and the AHV model constructed in TruckSim leads to the co-simulation platform. Under the emulated double lane-change test maneuver, the effects of the wireless communication with two schemes on the direction performance of the AHV are examined.


2006 ◽  
Vol 38 (1) ◽  
pp. 105-111 ◽  
Author(s):  
Thomas Troglauer ◽  
Tove Hels ◽  
Peter Falck Christens

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