We establish a simulation model based on the theory of air flow to analyze the accelerated release effect of the quick release valve inside the air brake control valve.In addition, the combined simulation system of tr...We establish a simulation model based on the theory of air flow to analyze the accelerated release effect of the quick release valve inside the air brake control valve.In addition, the combined simulation system of train air brake system and longitudinal train dynamics is used to analyze how the parameters of the quick release valve in the 120/120–1 brake control valve affect the propagation characteristics of the train brake pipe pressure wave, the release action range of the accelerated brake, and the longitudinal coupler force for a 20,000-ton heavy haul train on the section of the Datong–Qinhuangdao Railway. The results show that the quick release valve can effectively accelerate the rising speed of the train brake pipe pressure during the initial release, as the accelerated release effect is evident before the train brake pipe pressure reaches582 k Pa. The quick release valve can effectively accelerate the release of the rear cars, reducing the longitudinal coupler force impact due to time delay of the release process. The quick release valve can effectively reduce the tensile coupler force in the train by as much as 20% in certain cases.展开更多
In recent years, in order to implement the national green development requirements and implement the sustainable development strategy, the traditional wooden formwork and steel pipe scaffold can no longer meet the req...In recent years, in order to implement the national green development requirements and implement the sustainable development strategy, the traditional wooden formwork and steel pipe scaffold can no longer meet the requirements of energy conservation and environmental protection. With the increasingly fierce competition in the housing construction industry, the construction period and cost are continuously reduced. Under the dual pressure of national policy and market environment, the combined construction of aluminum alloy formwork and integrated attached lifting scaffold is timely and shows significant advantages. The combination of the aluminum formwork and the climbing frame is beneficial to the interpenetration of working procedures, the structure, decoration and outdoor works are carried out simultaneously, the construction waste is reduced, the cost of civilized measures is saved, the safety factor of operators is high, the aluminum formwork adopts a quick dismantling system, the construction period is saved, the rigidity of the aluminum formwork is large, the concrete forming quality is good, the turnover times are large, and the recycling value is high.展开更多
基金China National Railway Group Co.,Ltd(N2020J037).
文摘We establish a simulation model based on the theory of air flow to analyze the accelerated release effect of the quick release valve inside the air brake control valve.In addition, the combined simulation system of train air brake system and longitudinal train dynamics is used to analyze how the parameters of the quick release valve in the 120/120–1 brake control valve affect the propagation characteristics of the train brake pipe pressure wave, the release action range of the accelerated brake, and the longitudinal coupler force for a 20,000-ton heavy haul train on the section of the Datong–Qinhuangdao Railway. The results show that the quick release valve can effectively accelerate the rising speed of the train brake pipe pressure during the initial release, as the accelerated release effect is evident before the train brake pipe pressure reaches582 k Pa. The quick release valve can effectively accelerate the release of the rear cars, reducing the longitudinal coupler force impact due to time delay of the release process. The quick release valve can effectively reduce the tensile coupler force in the train by as much as 20% in certain cases.
文摘In recent years, in order to implement the national green development requirements and implement the sustainable development strategy, the traditional wooden formwork and steel pipe scaffold can no longer meet the requirements of energy conservation and environmental protection. With the increasingly fierce competition in the housing construction industry, the construction period and cost are continuously reduced. Under the dual pressure of national policy and market environment, the combined construction of aluminum alloy formwork and integrated attached lifting scaffold is timely and shows significant advantages. The combination of the aluminum formwork and the climbing frame is beneficial to the interpenetration of working procedures, the structure, decoration and outdoor works are carried out simultaneously, the construction waste is reduced, the cost of civilized measures is saved, the safety factor of operators is high, the aluminum formwork adopts a quick dismantling system, the construction period is saved, the rigidity of the aluminum formwork is large, the concrete forming quality is good, the turnover times are large, and the recycling value is high.
