Based on a series of numerical calculations, the behavior of flow field in obstructed square buoyant vertical jet is summarized and analyzed. Based on the axial line velocity distribution, the flow after the disc can ...Based on a series of numerical calculations, the behavior of flow field in obstructed square buoyant vertical jet is summarized and analyzed. Based on the axial line velocity distribution, the flow after the disc can be divided into three regions, i.e., recirculation region, transitional region and self-similar region The characteristic of selfsimilarity of upright velocity was validated. The three regions can also be distinguished based on the axial velocity. The axial velocity in self-similar region was found to obey the same law and the formula presented by introducing the velocity expression used by Chen and Rodi. The isolines of pressure on cross-sections of different heights were displayed and the production, expansion, breaking and disappearing of negative pressure regions were found.展开更多
This study selects six consecutive 18.6 years of global M≥7.0 earthquakes,calculates the lunar declination angle based on the time of the earthquakes,and divides the global earthquakes into 13 research regions accord...This study selects six consecutive 18.6 years of global M≥7.0 earthquakes,calculates the lunar declination angle based on the time of the earthquakes,and divides the global earthquakes into 13 research regions according to the global plate distribution facts to explore the lunar infl uence of earthquakes.The relationship between the lunar declination angle and these earthquakes is analyzed.The analysis results show that when the moon advances to a certain interval of its declination angle,the earthquakes are concentrated in a certain research region,whereas other research regions are relatively calm,providing a scientifi c basis for medium and long-term earthquake predictions in each research region.The 18.6-year cycle is the lunar declination angle change cycle,and it is also the major nutation cycle of the earth’s motion and lunar node movement cycle.This is,in reality,the eff ect of the lunar node tide,which is worthy of further study.展开更多
基金Project supported by the Planned Item for Excellent Young Teachers Invested by Education Ministry of China (No.2003-99)
文摘Based on a series of numerical calculations, the behavior of flow field in obstructed square buoyant vertical jet is summarized and analyzed. Based on the axial line velocity distribution, the flow after the disc can be divided into three regions, i.e., recirculation region, transitional region and self-similar region The characteristic of selfsimilarity of upright velocity was validated. The three regions can also be distinguished based on the axial velocity. The axial velocity in self-similar region was found to obey the same law and the formula presented by introducing the velocity expression used by Chen and Rodi. The isolines of pressure on cross-sections of different heights were displayed and the production, expansion, breaking and disappearing of negative pressure regions were found.
基金the National Natural Science Foundation of China(No.91736207)。
文摘This study selects six consecutive 18.6 years of global M≥7.0 earthquakes,calculates the lunar declination angle based on the time of the earthquakes,and divides the global earthquakes into 13 research regions according to the global plate distribution facts to explore the lunar infl uence of earthquakes.The relationship between the lunar declination angle and these earthquakes is analyzed.The analysis results show that when the moon advances to a certain interval of its declination angle,the earthquakes are concentrated in a certain research region,whereas other research regions are relatively calm,providing a scientifi c basis for medium and long-term earthquake predictions in each research region.The 18.6-year cycle is the lunar declination angle change cycle,and it is also the major nutation cycle of the earth’s motion and lunar node movement cycle.This is,in reality,the eff ect of the lunar node tide,which is worthy of further study.