On January 7,2025,a M 6.8 earthquake occurred at Dingri County,Shigatse City,Xizang Autonomous Region,which is the most largest earthquake in this region in the most recent five years.The maximum recorded peak ground ...On January 7,2025,a M 6.8 earthquake occurred at Dingri County,Shigatse City,Xizang Autonomous Region,which is the most largest earthquake in this region in the most recent five years.The maximum recorded peak ground acceleration in this earthquake is 0.43 g,which is significantly higher than the local design basis earthquake intensity level.This report focuses on the post-earthquake seismic damage investigation of rural selfbuilt houses and local public buildings,which shows quite different seismic performance.Collapse and heavy damage of rural self-built houses without seismic resistant measures were observed,while the masonry houses with seismic resistant measures show good seismic performance against collapse.The structural systems of public buildings with proper seismic design suffered slight seismic damage.Different form slight structural damage,the seismic damages of non-structural components,which resulted in the interruption of public building functionality were highlighted in this report.With the investigation results of seismic damage suffered by local houses and buildings,the casualty distribution and causes were analyzed in detail.展开更多
An experimental investigation of air flow and heat transfer in three types of converging-diverging tubes is presented in this study. They have the same diameter, rib height and pitch, but the different lengths of the ...An experimental investigation of air flow and heat transfer in three types of converging-diverging tubes is presented in this study. They have the same diameter, rib height and pitch, but the different lengths of the converging and diverging sections and their joint ways. The experimental results indicate that the heat transfer is enhanced when the length of converging section increases. A 12.4% increase of Nusselt number is observed and a 6.8% increase of friction coefficient is seen for the developed tube jointed linearly (DTL).Also a 5.27% increase of Nusselt number is observed and a 46.5% increase of friction coefficient is seen for the developed tube jointed convexly (DTC). The comparison results of Webb’s method show the DTL is better than OT in the range 1.5×10 4～4×10 4, but the DTC is not better than it.展开更多
With the help of the description methods in graph theory and the adaptive adjustment method, a steady sate simulation model for fin-and-tube heat exchanger with complex circuit arrangement was developed.This model cou...With the help of the description methods in graph theory and the adaptive adjustment method, a steady sate simulation model for fin-and-tube heat exchanger with complex circuit arrangement was developed.This model could provide better compatibility and accuracy for the design of heat exchanger with complex circuit arrangement.Using this model, six typical fin-and-tube heat exchangers with different circuit arrangements were analyzed.The counter flow arrangement could not always achieve the best performance.With appropriate compound arrangement, the performance of heat exchanger could be improved by 2%—4%.展开更多
基金funded by National Key Research and Development Program of China(2022YFC3803000).
文摘On January 7,2025,a M 6.8 earthquake occurred at Dingri County,Shigatse City,Xizang Autonomous Region,which is the most largest earthquake in this region in the most recent five years.The maximum recorded peak ground acceleration in this earthquake is 0.43 g,which is significantly higher than the local design basis earthquake intensity level.This report focuses on the post-earthquake seismic damage investigation of rural selfbuilt houses and local public buildings,which shows quite different seismic performance.Collapse and heavy damage of rural self-built houses without seismic resistant measures were observed,while the masonry houses with seismic resistant measures show good seismic performance against collapse.The structural systems of public buildings with proper seismic design suffered slight seismic damage.Different form slight structural damage,the seismic damages of non-structural components,which resulted in the interruption of public building functionality were highlighted in this report.With the investigation results of seismic damage suffered by local houses and buildings,the casualty distribution and causes were analyzed in detail.
文摘An experimental investigation of air flow and heat transfer in three types of converging-diverging tubes is presented in this study. They have the same diameter, rib height and pitch, but the different lengths of the converging and diverging sections and their joint ways. The experimental results indicate that the heat transfer is enhanced when the length of converging section increases. A 12.4% increase of Nusselt number is observed and a 6.8% increase of friction coefficient is seen for the developed tube jointed linearly (DTL).Also a 5.27% increase of Nusselt number is observed and a 46.5% increase of friction coefficient is seen for the developed tube jointed convexly (DTC). The comparison results of Webb’s method show the DTL is better than OT in the range 1.5×10 4～4×10 4, but the DTC is not better than it.
文摘With the help of the description methods in graph theory and the adaptive adjustment method, a steady sate simulation model for fin-and-tube heat exchanger with complex circuit arrangement was developed.This model could provide better compatibility and accuracy for the design of heat exchanger with complex circuit arrangement.Using this model, six typical fin-and-tube heat exchangers with different circuit arrangements were analyzed.The counter flow arrangement could not always achieve the best performance.With appropriate compound arrangement, the performance of heat exchanger could be improved by 2%—4%.
