Sample Applications of Transition Curves in Vertical Alignment

2017 ◽  
pp. 109-131
Author(s):  
Andrzej Kobryń
Keyword(s):  
Vertical Alignment ◽  
Transition Curves

scholarly journals Transition curves in vertical alignment as a method for reducing fuel consumption

2014 ◽  
Vol 9 (4) ◽  
pp. 260-268 ◽  
Author(s):  
Andrzej Kobryń
Keyword(s):  
Fuel Consumption ◽  
Comparative Studies ◽  
Vertical Alignment ◽  
New Approach ◽  
Numerical Studies ◽  
Fuel Consumption Reduction ◽  
Consumption Reduction ◽  
Straight Lines ◽  
Transition Curves ◽  
Methods Numerical

This paper presents a new approach to the fuel consumption reduction. This approach is based on vertical curve designs based on transition curves. The work presents selected curves, which are used for this purpose. Moreover, the results of comparative studies are shown for these curves, carried out in order to compare the possible reduction of fuel consumption in vertical curves designed using both conventional and proposed methods. Numerical studies were based on German engineering guidelines. In the case of vertical arcs formed by transition curves, fuel consumption indexes prove to be significantly lower than in curves based on a grade line consisting of straight lines with parabolic arcs. The obtained results indicate the advisability of forming vertical curves using transition curves.

scholarly journals S-Shaped Transition Curves as an Element of Reverse Curves in Road Design

2019 ◽  
Vol 14 (4) ◽  
pp. 484-503 ◽  
Author(s):  
Andrzej Kobryń ◽  
Piotr Stachera
Keyword(s):  
Research Topic ◽  
Vertical Alignment ◽  
Geometric Properties ◽  
Road Design ◽  
Geometric Systems ◽  
Practical Usefulness ◽  
Circular Curves ◽  
Traditional Approaches ◽  
Transition Curves

A road designing involves horizontal and vertical alignment. The horizontal geometry is formed by straight and curvilinear sections that are traditionally formed using circular and transition curves (mainly the clothoid). Different geometric systems that are designed using circular and transition curves are between others circular curves with symmetrical or unsymmetrical clothoids, combined curves, oval curves and reverse curves. Designing these systems is quite complex. Therefore, so-called S-shaped transition curves are an alternative to traditional approaches. These curves are known from literature and are modern geometric tools for the shaping of reverse curves. The paper analyses the basic geometric properties of these curves as well as compare to the geometry of the appropriate geometric systems, which are formed with clothoid or using S-shaped transition curves. In addition, a procedure for designing reverse curves using S-shaped transition curves was proposed. Another research topic was the comparison of the analysed reverse curves (created using polynomial transition curves) with traditional curves (created using the clothoid). The results of the studies, despite the noticeable differences in the geometry of the compared components, confirm the practical usefulness of the S-shaped transition curves for designing the geometry of the route.

Influence of Vertical Alignment of Expressway Tunnel on Traffic Safety of Tunnel

CICTP 2020 ◽  
2020 ◽  
Author(s):  
Yifei Zhao ◽  
Jun Wang ◽  
Shunchao Yin ◽  
Jiaqing He ◽  
Zhongyi Chen
Keyword(s):  
Traffic Safety ◽  
Vertical Alignment

48.3: Distinguished Paper: A Novel Hole Induced Vertical Alignment LC Mode with Superior Transmittance

2010 ◽  
Vol 41 (1) ◽  
pp. 725 ◽  
Author(s):  
Y. K. Jang ◽  
S. J. Lee ◽  
J. Y. Lee ◽  
Y. Li ◽  
J. H. Hwang ◽  
...  
Keyword(s):  
Vertical Alignment

scholarly journals Dimensionless Correlations for Natural Convection Heat Transfer from a Pair of Vertical Staggered Plates Suspended in Free Air

2021 ◽  
Vol 11 (14) ◽  
pp. 6511
Author(s):  
Alessandro Quintino ◽  
Marta Cianfrini ◽  
Ivano Petracci ◽  
Vincenzo Andrea Spena ◽  
Massimo Corcione
Keyword(s):  
Heat Transfer ◽  
Rayleigh Number ◽  
Convection Heat Transfer ◽  
Separation Distance ◽  
Vertical Alignment ◽  
Maximum Heat ◽  
Plate Length ◽  
Optimal Separation ◽  
Maximum Heat Transfer ◽  
Free Air

Buoyancy-induced convection from a pair of staggered heated vertical plates suspended in free air is studied numerically with the main scope to investigate the basic heat and momentum transfer features and to determine in what measure any independent variable affects the thermal performance of each plate and both plates. A computational code based on the SIMPLE-C algorithm for pressure-velocity coupling is used to solve the system of the governing conservation equations of mass, momentum and energy. Numerical simulations are carried out for different values of the Rayleigh number based on the plate length, as well as of the horizontal separation distance between the plates and their vertical alignment, which are both normalized by the plate length. It is observed that an optimal separation distance between the plates for the maximum heat transfer rate related to the Rayleigh number and the vertical alignment of the plates does exist. Based on the results obtained, suitable dimensionless heat transfer correlations are developed for each plate and for the entire system.

Stability of a Rigid Body With an Oscillating Particle: An Application of MACSYMA

1985 ◽  
Vol 52 (3) ◽  
pp. 686-692 ◽  
Author(s):  
L. A. Month ◽  
R. H. Rand
Keyword(s):  
Angular Velocity ◽  
Rigid Body ◽  
Classical Problem ◽  
Moment Of Inertia ◽  
Model Parameters ◽  
Stability Chart ◽  
The Stability ◽  
Transition Curves ◽  
Minimum Moment ◽  
Small Angular Velocity

This problem is a generalization of the classical problem of the stability of a spinning rigid body. We obtain the stability chart by using: (i) the computer algebra system MACSYMA in conjunction with a perturbation method, and (ii) numerical integration based on Floquet theory. We show that the form of the stability chart is different for each of the three cases in which the spin axis is the minimum, maximum, or middle principal moment of inertia axis. In particular, a rotation with arbitrarily small angular velocity about the maximum moment of inertia axis can be made unstable by appropriately choosing the model parameters. In contrast, a rotation about the minimum moment of inertia axis is always stable for a sufficiently small angular velocity. The MACSYMA program, which we used to obtain the transition curves, is included in the Appendix.

Catalyst-Free Growth of Vertical Alignment ZnO Nanowire Arrays by a Two-Stage Process

2009 ◽  
Vol 113 (52) ◽  
pp. 21572-21576 ◽  
Author(s):  
Liang-Yih Chen ◽  
Shu-Han Wu ◽  
Yu-Tung Yin
Keyword(s):  
Nanowire Arrays ◽  
Zno Nanowire ◽  
Vertical Alignment ◽  
Two Stage ◽  
Catalyst Free ◽  
Zno Nanowire Arrays ◽  
Stage Process ◽  
Free Growth

scholarly journals Vertical alignment of stagnation points in pseudo-plane ideal flows

AIP Advances ◽  
2017 ◽  
Vol 7 (9) ◽  
pp. 095314 ◽  
Author(s):  
Che Sun
Keyword(s):  
Vertical Alignment ◽  
Stagnation Points
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