A simulation approach to calculate gear dynamic-factors for high-speed applications

Author(s):  
S. Jain ◽  
B. James
2018 ◽  
Vol 24 ◽  
pp. 8-14 ◽  
Author(s):  
David Meinel ◽  
Tallal Javied ◽  
Sebastian Rast ◽  
Christian Zipp ◽  
Jörg Franke

1975 ◽  
Vol 97 (2) ◽  
pp. 151-155 ◽  
Author(s):  
R. G. Davies ◽  
C. L. Magee

The tensile strength of seventeen engineering materials including steels, Al alloys, and fiber-reinforced plastics, has been determined at strain-rates from 10−3 to 103 sec−1. Variable effects on the stress-strain behavior were found in the different materials with the Al alloys showing minimal strain-rate sensitivity and the plastics highest. All results exhibit a logarithmic dependence of flow stress on strain-rate and thus the dynamic factors (ratio of dynamic to low rate or quasi-static strengths) are as dependent upon changes in quasi-static testing speed (∼1 in./min (0.42 mm/s) as they are to changes at high speed (50,000 in./min or 50 mph (22.35 m/s). No significant influence of strain-rate on elongation or reduction in area has been found for any of the materials. Steels, which comprise the majority of the presently investigated materials, exhibit a higher rate sensitivity for yielding than for higher strain deformation. It is shown that the flow stress results for these steels leads to an internally consistent scheme when (1) strength level and (2) strengthening mechanisms are properly accounted for.


Author(s):  
Brian Anichowski ◽  
Ahmet Kahraman ◽  
David Talbot

This paper complements recent investigations [Handschuh et al (2014), Talbot et al (2016)] of the influences of tooth indexing errors on dynamic factors of spur gears by presenting data on changes to the dynamic transmission error. An experimental study is performed using an accelerometer-based dynamic transmission error measurement system incorporated into a high-speed gear tester to establish baseline dynamic behavior of gears having negligible indexing errors, and to characterize changes to this baseline due to application of tightly-controlled intentional indexing errors. Spur test gears having different forms of indexing errors are paired with a gear having negligible indexing error. Dynamic transmission error of gear pairs under these error conditions is measured and examined in both time and frequency domains to quantify the transient effects induced by these indexing errors. Both measurements indicate clearly that the baseline dynamic response, dominated by well-defined resonance peaks and mesh harmonics, are complemented by non-mesh orders of transmission error due the transient behavior induced by indexing errors.


2020 ◽  
Vol 313 ◽  
pp. 00001
Author(s):  
Leonid Diachenko ◽  
Andrey Benin

The article deals with the parameters of high-speed trains effect on the unified simple-span girder reinforced concrete bridge superstructures on conventional railways using a simplified methodology of determining maximum vertical accelerations and live load dynamic factors. It is noted that the dynamic additions to the stress-strain behavior components (bending moments, transverse force and vertical sags) differ from each other. The presented methodology of dynamic factors determination helps to make a dynamic calculation and to identify general forces in simple-span girder superstructures without numerical simulation and straightforward dynamic analysis, which greatly reduces labor intensity of the design works. Based on the dynamic calculation results, a conclusion is made that the unified simple-span girder reinforced concrete bridge superstructures can be applied on high-speed railways, and the scope of their application is specified.


Author(s):  
Hamed Pouryousef ◽  
Monique Stewart ◽  
Som P. Singh ◽  
Anand Prabhakaran

Abstract Over the last decades there have been major technology advancements in the railroad industry to improve the operational safety as well as performance of freight trains in shared-use corridors. This study was focused on developing a methodology that allows evaluation of the impact of such advanced technologies over the safety and capacity aspects of the U.S. rail network using a benchmark mini-network simulation approach. A hypothetical mini-network of 5,000 miles of track with characteristics typical of the North American rail network was developed. Two hundred thirty two (232) daily trains, including a mix of intercity passenger, commuter, High Speed Rail and 78 freight trains, were used to simulate the traffic flow. Several network capacity and safety related parameters; network delay, network velocity, track utilization level, number of stops at stations, number of braking for route reservations, and number of stops at signals were analyzed in this study. The results of the benchmark network simulations were then extended to the U.S. rail network, using an analytical technique with assumptions for important parameters and impact factors such as total route miles, freight train-miles, number of sidings/yards, congestion level and age of fleets. The results indicate that the methodology is able to quantify the improvement in network capacity and safety features that can be obtained when advanced technologies are deployed on freight trains.


Author(s):  
Leonid Dyachenko ◽  
Andrey Benyn ◽  
Vladimir Smyrnov

Objective: Improvement of dynamic analysis method of simple beam spans in the process of high-speed trains impact. Methods: Mathematical modeling with numerical and analytical methods of building mechanics was applied. Results: The parameters of high-speed trains influence on simple beam spans of bridges were analyzed. The method of dynamic factor to live load determination was introduced. The reliability of the method in question was corroborated by the results of numerical simulation of high-speed trains’ movement by beam spans with different speeds. The introduced algorithm of dynamic analysis was based on the connection between maximum acceleration of a beam span in resonance vibration mode and the basic factors of stress-strain state. The method in question makes it possible to determine both maximum and bottom values of main loading in a construction, which determines the possibility of endurance tests. It was noted that dynamic additions for the components of stress-strain state (bending moments, shear force, vertical deflections) were different. The fact in question determines the necessity of differential approach application to identify dynamic factors in the process of calculation testing on the first and the second groups of limit states. Practical importance: The method of dynamic factors’ determination presented in the study makes it possible to perform dynamic analysis and determine the main loading in simple beam spans without application of numerical modeling and direct analytical analysis, which considerably reduces labor costs on engineering.


2014 ◽  
Vol 1030-1032 ◽  
pp. 2742-2745
Author(s):  
Yong Dou

With computer simulation approach and theoretical mechanics analysis approach, according to two kinds of the loop plays, the author studied and compared the state change laws of loop after colliding. The two kinds of results received in analysis are identical. The speed of high-speed loop slows down to some extent, but rotate is strengthened, and the speed of high-spin loop drive is accelerated, but rotate is weaken. The paper indicates that computer simulation technology can be applied to dynamics study and state measurement of table tennis, and it also has certain guidable meaning for practicing.


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