A flexible flat torque converter was proposed to fulfill the requirement of miniaturization and power density maximization for automobiles.Constructed by two arcs joined by lines,the torus was designed directly from d...A flexible flat torque converter was proposed to fulfill the requirement of miniaturization and power density maximization for automobiles.Constructed by two arcs joined by lines,the torus was designed directly from design path.The influence of flatness on the performance of the torque converter was evaluated.The software CFX and standard k-ε model were adopted to simulate the internal flow fields of the torque converter under different flatness ratios.The results indicated that the performance of the torque converter got worse as the flatness declined,but the capacity of pump increased.The efficiency and the torque ratio dropped slightly as the flatness ratio decreased.So the torque converter could be squashed appropriately to get high power density without too much efficiency sacrifice.But when the flatness ratio was below 0.2,there was a significant drop in the efficiency.展开更多
The performance of a helical soil nailed structure is dependent on the installation torque required and the consequent pullout resistance developed.The present research work aims at proposing theoretical models to est...The performance of a helical soil nailed structure is dependent on the installation torque required and the consequent pullout resistance developed.The present research work aims at proposing theoretical models to estimate the required torque during installation of helical soil nails.Moreover,theoretical models are also developed to predict the pullout capacity of single and group of the helical nail for uniform and staggered arrangements.The proposed model predicts the pure-elastic and elastic-plastic pullout behavior of different helical nails.An equation for estimating the capacity-totorque Ratio(Kt)has also been developed for different nail shaft diameters.The results from the proposed models are validated with experimental results obtained from model testing of both single and group of helical nails.The predicted results are also compared for validation with the published literature.The results for installation torque and pullout load depict that the developed models predict values which are in accordance with the experimental results and are also found in good agreement with the published literature.Thus,the proposed models can effectively be used by the filed engineers for estimating the required installation torque and corresponding pullout capacities for single or double plate helical soil nails in cohesionless soil under surcharge pressure range of 0–50k Pa.展开更多
基金Supported by the National Natural Science Foundation of China (50905016)
文摘A flexible flat torque converter was proposed to fulfill the requirement of miniaturization and power density maximization for automobiles.Constructed by two arcs joined by lines,the torus was designed directly from design path.The influence of flatness on the performance of the torque converter was evaluated.The software CFX and standard k-ε model were adopted to simulate the internal flow fields of the torque converter under different flatness ratios.The results indicated that the performance of the torque converter got worse as the flatness declined,but the capacity of pump increased.The efficiency and the torque ratio dropped slightly as the flatness ratio decreased.So the torque converter could be squashed appropriately to get high power density without too much efficiency sacrifice.But when the flatness ratio was below 0.2,there was a significant drop in the efficiency.
文摘The performance of a helical soil nailed structure is dependent on the installation torque required and the consequent pullout resistance developed.The present research work aims at proposing theoretical models to estimate the required torque during installation of helical soil nails.Moreover,theoretical models are also developed to predict the pullout capacity of single and group of the helical nail for uniform and staggered arrangements.The proposed model predicts the pure-elastic and elastic-plastic pullout behavior of different helical nails.An equation for estimating the capacity-totorque Ratio(Kt)has also been developed for different nail shaft diameters.The results from the proposed models are validated with experimental results obtained from model testing of both single and group of helical nails.The predicted results are also compared for validation with the published literature.The results for installation torque and pullout load depict that the developed models predict values which are in accordance with the experimental results and are also found in good agreement with the published literature.Thus,the proposed models can effectively be used by the filed engineers for estimating the required installation torque and corresponding pullout capacities for single or double plate helical soil nails in cohesionless soil under surcharge pressure range of 0–50k Pa.
