scholarly journals Research on Simulation Calculation of the Safety of Tight-Lock Coupler Curve Coupling

Symmetry ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1997
Author(s):  
Hai Zhang ◽  
Chenyu Zhang ◽  
Fengtao Lin ◽  
Xiugang Wang ◽  
Gengzhe Fu

Once a train breaks down on a busy railway line, it will affect the whole traffic network. However, when a rescue locomotive is hooked up to the broken train for towing it to the next station, it is common that coupling dislocation occurs, which results in damages to couplers and the driver’s cab. To ensure the safety of the trains during the coupling, it becomes crucial to determine whether they can be linked safely and automatically under different line conditions. In this paper, position and pose of the rescue locomotive and the broken train on the line are calculated by geometric analytical calculation method, which determines the position relation of their couplers. Then a so-called “coupling characteristic triangle” was proposed to determine whether trains can be safely and automatically linked on the railway line. The triangles are constructed by the peak points of the couplers head of the front vehicle and the rear one and border lines of secure coupling area on the couplers. By judging the shape of the triangle, it can directly judge whether their couplers can be connected successfully. The method has been applied to check the safety of the trains during coupling on the Nanchang urban railway Line 4. The results show that the maximum swing angle of the coupler reaches 17.3957° in the straight–curve section with a radius of 325 m. At this time, coupling is most difficult, and trains need to be connected manually through the tractor; all the calculation results are verified in the actual line. By comparing different calculation methods for judging coupling safety, it is shown that the method proposed in this paper is accurate, efficient, and users can judge coupling safety more intuitively.

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1265 ◽  
Author(s):  
Johanna Geis-Schroer ◽  
Sebastian Hubschneider ◽  
Lukas Held ◽  
Frederik Gielnik ◽  
Michael Armbruster ◽  
...  

In this contribution, measurement data of phase, neutral, and ground currents from real low voltage (LV) feeders in Germany is presented and analyzed. The data obtained is used to review and evaluate common modeling approaches for LV systems. An alternative modeling approach for detailed cable and ground modeling, which allows for the consideration of typical German LV earthing conditions and asymmetrical cable design, is proposed. Further, analytical calculation methods for model parameters are described and compared to laboratory measurement results of real LV cables. The models are then evaluated in terms of parameter sensitivity and parameter relevance, focusing on the influence of conventionally performed simplifications, such as neglecting house junction cables, shunt admittances, or temperature dependencies. By comparing measurement data from a real LV feeder to simulation results, the proposed modeling approach is validated.


2012 ◽  
Vol 134 (4) ◽  
Author(s):  
Zhengmei Li ◽  
Qiong Zhou ◽  
Jianping Tang ◽  
Jianwen Wang ◽  
Qi An

Taking the water pump bearing with one roller row (WR)-type auto water pump bearing as a research sample, an analytical calculation method is developed to improve the accuracy and efficiency of the current calculations for the bearing loads and life in engineering application. Considering the misalignment due to the deflection of the bearing spindle, the bearing internal loads and deformations under the action of the complicated external space loads are obtained. The bearing fatigue life including the lives of the rollers and the balls is also calculated with considering the non-normal load distribution caused by the spindle deflection and the roller tilt. The bearing load and life calculation results are compared with those calculated by the traditional method in which the deflection of the bearing spindle and the roller tilt are ignored. The effects of the bearing spindle deflection on the load distribution and the life of the auto water pump bearing are analyzed and discussed. The life decrease in the auto water pump bearing is significant due to the deflection of the bearing spindle and it is recommended to give more attention to this deflection for the high quality of the bearing design and calculation.


Author(s):  
Wadie Kidess

In order to get the authorization for issuing energy performance certificates in Slovenia, the expert candidate has to attend the prescribed course and pass the exam. The simplified method for heat losses calculation that is taught at this course neglects the thermal bridges, raising concerns whether the calculation results are reliable. In this paper we have compared three methods for calculation of thermal losses for a “typical” family house. The first is the above mentioned simplified calculation using a correctional factor; the second takes into account the thermal bridges, using linear thermal transmittances obtained by numerical calculation, and the third takes into account the thermal bridges, using default values for linear thermal transmittances. Noting that the second method returns the most exact values, we have found that the first method results are too large, yet still smaller than the third method results.


Akustika ◽  
2021 ◽  
pp. 100-106
Author(s):  
sergey Timushev ◽  
Alexey Yakovlev ◽  
Petr Moshkov

The problem of simulation the noise generated during the operation of the propeller is considered. Calculation methods are described and numerical simulation of the noise of a light aircraft propeller by the acoustic-vortex method is performed. The results of numerical modeling of the tonal components of the propeller noise when operating under static conditions are compared with experimental data and calculation results based on a semiempirical model.


2020 ◽  
Vol 30 ◽  
pp. 102288
Author(s):  
Gilnaz Omyan ◽  
Somayeh Gholami ◽  
Abbas Ghasemi Zad ◽  
Mara Severgnini ◽  
Francesco Longo ◽  
...  

Author(s):  
Rongyan Zhu ◽  
Xiaofen Zhou ◽  
Lizhe Shi ◽  
Shufan Zhu

Logistics resources will be concentrated in the same space by logistics park, to provide intensive logistics services and enhance the efficiency of logistics, thereby, a large number of logistics parks emerged in China for a period of time, and the park vacancy rate caused by high attention. Logistics Park construction should be matched with the demand. Calculation of logistics park carrying capacity is one of those problems should be solved. This paper uses the analogy method, the standard reference method and the space-time consumption method to calculate the comprehensive carrying capacity of “one port, six parks”, which is planned in Wuhan. The results show that although the space-time consumption method is more complicated than the other two, but its calculation results can better reflect the carrying capacity of Logistics Park.


2012 ◽  
Vol 166-169 ◽  
pp. 610-615
Author(s):  
Yong Yang ◽  
Kang An ◽  
Su Sheng Zeng ◽  
Jian Yang Xue

Based on the experiment results of five plain steel plate-light weight concrete hollow deck specimens, the design methods of the composite decks which mainly including the calculation method of the bearing capacity and calculation method of the flexural rigidity were introduced. In the paper, the bearing capacity and flexural rigidity of the composite at two orthogonal directions, which including the direction parallel to the pipes and the direction perpendicular to the pipes, were both introduced. The calculation results of the bearing capacity and middle-span deflection were in good agreement with those of the experimental results, and in the return calculation methods were verified. Therefore, the design methods and calculation methods were useful to the design of this new type composite deck.


2013 ◽  
Vol 300-301 ◽  
pp. 327-332
Author(s):  
Guo Liang Wang ◽  
Ji Ye Zhang ◽  
Xiao Hui Xu ◽  
Ming Li

A new hybrid power system with the “power grid-battery-ultracapacitor” was presented. The coupling relationship between the new hybrid power system and train driving was studied on the basis of considering the coupling relationship between train dynamics and the new hybrid power system. A traction simulation system was established. It could be used for traction simulation calculation on hybrid power train. It provided support for dynamics analysis of the new hybrid power train, design and optimization of the new hybrid power system and optimization of the train operation. In the end, traction simulation calculation for hybrid power train was done with actual line. The calculation results provided strong support for the development of the hybrid power train.


2011 ◽  
Vol 201-203 ◽  
pp. 367-371
Author(s):  
Li Zhang

In view of the deficiency in calculation precision of turbine diameter at present, the mathematics model of energy distribution on swept area of the down wind turbine was proposed, and the energy expression that taked into account wind shear and tower shade effect was also accurately deduced.Combining with the concrete case, three different calculation methods about turbine dimeter were respectively solved.The calculation results show that the influence of wind shear is really little in turbine diameter calculation.The influentce of tower shade effect is obvious,while the influence of tower height is maximal. There is approximately a linear relationship between the turbine diameter and the tower diameter. The tower height has the maximum. There is a optimum match relationship that satisfies the demand of energy output in the down wind turbine.


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