The Late Cretaceous tectonic upheaval was an important event during the evolution of the Qaidam Basin, resulting in the omission of the Upper Cretaceous in the whole basin and unconformities between the Paleogene sequ...The Late Cretaceous tectonic upheaval was an important event during the evolution of the Qaidam Basin, resulting in the omission of the Upper Cretaceous in the whole basin and unconformities between the Paleogene sequence and pre-K2 strata. Inte-grating geological and geophysical data, two different groups of Late Cretaceous faults were recognized in the study area, one group consisting of E-W extending strike-slip faults (e.g., the Maxian and Yema-Jinan faults in the Mahai area, which caused an E-W omission zone of Mesozoic), while the other one has NW-SE thrust faults, resulting in NW-SE fold-and-thrust belts. Considering the different strikes and scale of these two groups, a simple-shear model has been employed to explain this structural phenomenon. The NW-SE thrust faults were thought to be subsidiary to the E-W strike-slip faults. Putting this into the framework of the Cretaceous paleogeographic environment of central Asia, it is inferred that this tectonic event of the Qaidam Basin is a response to the continuous northward drifting of the India plate.展开更多
Heat transfer in the evacuated collector tube is a three-dimensional laminar natural convection prob-lem driven by buoyancy. Because of its complexity, no effective theoretical model is available despiteof limited exp...Heat transfer in the evacuated collector tube is a three-dimensional laminar natural convection prob-lem driven by buoyancy. Because of its complexity, no effective theoretical model is available despiteof limited experimental work which is confined to one aspect- The present work aims to depict theconvective heat transfer inside a tweended inclined tube with East-West symmetric heat input us-ing numerical methods. Based on reasonable assumptions, governing equations of the inside fluid areestabllshed. The corresponding discretizated equations are solved by employing numerical methods.The calculated results are displayed for velocity and temperature profiles on different cross-sectionalplanes, which present the flow pattern characterized by upflow and dowallow along the axial direc-tion and adherent flow along the peripheral direction, and the heat transfer process from the wall tothe center. Furthermore, the transient Nusselt number and average temperature level are shown anddiscussed. Finally, the parametric effects of the tube radius and the heat input on the flow and heattransfer are also given.展开更多
文摘The Late Cretaceous tectonic upheaval was an important event during the evolution of the Qaidam Basin, resulting in the omission of the Upper Cretaceous in the whole basin and unconformities between the Paleogene sequence and pre-K2 strata. Inte-grating geological and geophysical data, two different groups of Late Cretaceous faults were recognized in the study area, one group consisting of E-W extending strike-slip faults (e.g., the Maxian and Yema-Jinan faults in the Mahai area, which caused an E-W omission zone of Mesozoic), while the other one has NW-SE thrust faults, resulting in NW-SE fold-and-thrust belts. Considering the different strikes and scale of these two groups, a simple-shear model has been employed to explain this structural phenomenon. The NW-SE thrust faults were thought to be subsidiary to the E-W strike-slip faults. Putting this into the framework of the Cretaceous paleogeographic environment of central Asia, it is inferred that this tectonic event of the Qaidam Basin is a response to the continuous northward drifting of the India plate.
文摘Heat transfer in the evacuated collector tube is a three-dimensional laminar natural convection prob-lem driven by buoyancy. Because of its complexity, no effective theoretical model is available despiteof limited experimental work which is confined to one aspect- The present work aims to depict theconvective heat transfer inside a tweended inclined tube with East-West symmetric heat input us-ing numerical methods. Based on reasonable assumptions, governing equations of the inside fluid areestabllshed. The corresponding discretizated equations are solved by employing numerical methods.The calculated results are displayed for velocity and temperature profiles on different cross-sectionalplanes, which present the flow pattern characterized by upflow and dowallow along the axial direc-tion and adherent flow along the peripheral direction, and the heat transfer process from the wall tothe center. Furthermore, the transient Nusselt number and average temperature level are shown anddiscussed. Finally, the parametric effects of the tube radius and the heat input on the flow and heattransfer are also given.