This paper describes the measurements and analysis of an experimental campaign performed in different urban street in Aswan, Egypt. The present study is focused on the experimental investigation of thermal characteris...This paper describes the measurements and analysis of an experimental campaign performed in different urban street in Aswan, Egypt. The present study is focused on the experimental investigation of thermal characteristics during summer 2012 of five different regions location (building on Nile river shore, building in front of a mountain, building under high power transmission line, two building opposite other in resident region, finally ship in Nile river) aiming at the investigation of the impact of urban location on the potential of natural and hybrid ventilation under hot weather conditions. The temporal and spatial distribution of air and surface temperatures is examined. Emphasis was given on the vertical distribution of air and surface temperatures. The results showed that the measured surface temperature across the street was the highest value than the air and wall temperature where temperature difference between street and air temperature could reach 35℃ and this favored the overheating of lower air levels. Buoyancy generated mainly from asphalt-street heating resulted in the development of the predominant recirculation inside the street canyon. The results also show that air temperature for two building opposite other has a lower value followed by building on Nile river shore followed by building at front of mountain.展开更多
On the interface of the Cu-Al composite plate from horizontal continuous casting,the eutectic microstructure layer thickness ac-counts for more than 90%of the total interface thickness,and the deformation in rolling f...On the interface of the Cu-Al composite plate from horizontal continuous casting,the eutectic microstructure layer thickness ac-counts for more than 90%of the total interface thickness,and the deformation in rolling forming plays an important role in the quality of the composite plate.The eutectic microstructure material on the interface of the Cu-Al composite plate was prepared by changing the cooling rate of ingot solidification and the deformation in hot compression was investigated.The results show that when the deformation temperature is over 300℃,the softening effect of dynamic recrystallization ofα-Al is greater than the hardening effect,and uniform plastic deformation of eutectic microstructure is caused.The constitutive equation of flow stress in the eutectic microstructure layer was established by Arrhenius hy-perbolic-sine mathematics model,providing a reliable theoretical basis for the deformation of the Cu-Al composite plate.展开更多
文摘This paper describes the measurements and analysis of an experimental campaign performed in different urban street in Aswan, Egypt. The present study is focused on the experimental investigation of thermal characteristics during summer 2012 of five different regions location (building on Nile river shore, building in front of a mountain, building under high power transmission line, two building opposite other in resident region, finally ship in Nile river) aiming at the investigation of the impact of urban location on the potential of natural and hybrid ventilation under hot weather conditions. The temporal and spatial distribution of air and surface temperatures is examined. Emphasis was given on the vertical distribution of air and surface temperatures. The results showed that the measured surface temperature across the street was the highest value than the air and wall temperature where temperature difference between street and air temperature could reach 35℃ and this favored the overheating of lower air levels. Buoyancy generated mainly from asphalt-street heating resulted in the development of the predominant recirculation inside the street canyon. The results also show that air temperature for two building opposite other has a lower value followed by building on Nile river shore followed by building at front of mountain.
基金This work was financially supported by the National Key Research and Development Program of China(No.2018YFA0707303)the National Natural Science Foundation for Distinguished Young Scholars of China(No.51925401).
文摘On the interface of the Cu-Al composite plate from horizontal continuous casting,the eutectic microstructure layer thickness ac-counts for more than 90%of the total interface thickness,and the deformation in rolling forming plays an important role in the quality of the composite plate.The eutectic microstructure material on the interface of the Cu-Al composite plate was prepared by changing the cooling rate of ingot solidification and the deformation in hot compression was investigated.The results show that when the deformation temperature is over 300℃,the softening effect of dynamic recrystallization ofα-Al is greater than the hardening effect,and uniform plastic deformation of eutectic microstructure is caused.The constitutive equation of flow stress in the eutectic microstructure layer was established by Arrhenius hy-perbolic-sine mathematics model,providing a reliable theoretical basis for the deformation of the Cu-Al composite plate.