The successful exploration and production of shale-gas resources in the United States and Canada sets a new possible solution towards the energy crisis presently affecting most countries of Asia. This study focuses on...The successful exploration and production of shale-gas resources in the United States and Canada sets a new possible solution towards the energy crisis presently affecting most countries of Asia. This study focuses on the use of well log and 2D seismic data for the characterization of the shale oil/gas potential of a Paleocene-Eocene succession -- the Meyal area in the Potwar Basin of Pakistan. Two shaly plays are identified in Paleocene-Eocene strata in well logs using ALogR and modified ALogR cross-plot techniques. The results indicate that Paleocene shale （the Patala Formation） and the lower shaly part of Eocene limestone （Sakesar Formation） can be potentially mature source rocks. However, the thermal maturity modelling proves that only the Paleocene shale is mature. Our results also suggest that the maturity responses on ALogR models for the lower shaly part of the Eocene limestone are due to trapped hydrocarbons in the intra-formational fractures. Petroelastic/petrophysical analysis of the Patala Formation reveals two potential shale oil/gas zones on the basis of Young＇s modulus, Poisson＇s ratio, Brittleness index and Total Organic Content at an exploitation depth of 3980-3988 m. This work can provide valuable insight for estimating shale oil/gas potential in highly deformed basins not only in Asia but in other parts of the world.展开更多
In this investigation,we have studied the peristaltic fluid flow in an asymmetric channel with convective walls.Fourth grade fluid model has been utilized in view of the fact that the results of all other differential...In this investigation,we have studied the peristaltic fluid flow in an asymmetric channel with convective walls.Fourth grade fluid model has been utilized in view of the fact that the results of all other differential type models can be deduced as the special case.Combined effects of heat and mass transfer are considered.The thermophoresis effects occur in the energy equation.Convective heat and mass boundary conditions have been given special attention.Long wave length and low Reynolds number approximations are utilized for the simplifications.Approximate analytic solutions for the velocity,temperature and concentration profiles are calculated using perturbation technique and elaborated in the form of graphical observations for various physical quantities.展开更多
Hierarchical connection(HC)is a very attractive mode for±800 kV line commutated converter based ultra high voltage direct current(LCC-UHVDC)system connected to different AC voltage levels because of its ability t...Hierarchical connection(HC)is a very attractive mode for±800 kV line commutated converter based ultra high voltage direct current(LCC-UHVDC)system connected to different AC voltage levels because of its ability to reduce the scale factor of a converter transformer.Faults in the HC-UHVDC system can cause commutation failure(CF).In this paper,impact of synchronous condenser(SC)to mitigate CF in HC-UHVDC system is analyzed.A±800KV HC-UHVDC system along with synchronous condenser is built in PSCAD/EMTDC.Transient performance analysis of HC-UHVDC for single and three phase to ground faults is investigated.Commutation failure immunity index(CFII),commutation failure probability index(CFPI),fault recovery time(FRT),and transient overvoltage(TOV)are used as measures to evaluate the effects of SC at HC-UHVDC system design.The simulation results show that SC can make the HCUHVDC system less susceptible to CF,effectively improve fault recovery performances of the overall system,and reduce transient overvoltage when single or multiple converters are blocked.The results of this research can provide technical assistance in real world HC-UHVDC projects.展开更多
文摘The successful exploration and production of shale-gas resources in the United States and Canada sets a new possible solution towards the energy crisis presently affecting most countries of Asia. This study focuses on the use of well log and 2D seismic data for the characterization of the shale oil/gas potential of a Paleocene-Eocene succession -- the Meyal area in the Potwar Basin of Pakistan. Two shaly plays are identified in Paleocene-Eocene strata in well logs using ALogR and modified ALogR cross-plot techniques. The results indicate that Paleocene shale （the Patala Formation） and the lower shaly part of Eocene limestone （Sakesar Formation） can be potentially mature source rocks. However, the thermal maturity modelling proves that only the Paleocene shale is mature. Our results also suggest that the maturity responses on ALogR models for the lower shaly part of the Eocene limestone are due to trapped hydrocarbons in the intra-formational fractures. Petroelastic/petrophysical analysis of the Patala Formation reveals two potential shale oil/gas zones on the basis of Young＇s modulus, Poisson＇s ratio, Brittleness index and Total Organic Content at an exploitation depth of 3980-3988 m. This work can provide valuable insight for estimating shale oil/gas potential in highly deformed basins not only in Asia but in other parts of the world.
文摘In this investigation,we have studied the peristaltic fluid flow in an asymmetric channel with convective walls.Fourth grade fluid model has been utilized in view of the fact that the results of all other differential type models can be deduced as the special case.Combined effects of heat and mass transfer are considered.The thermophoresis effects occur in the energy equation.Convective heat and mass boundary conditions have been given special attention.Long wave length and low Reynolds number approximations are utilized for the simplifications.Approximate analytic solutions for the velocity,temperature and concentration profiles are calculated using perturbation technique and elaborated in the form of graphical observations for various physical quantities.
基金The authors gratefully acknowledge the financial support from the National Science Foundation of China(No.51507060).
文摘Hierarchical connection(HC)is a very attractive mode for±800 kV line commutated converter based ultra high voltage direct current(LCC-UHVDC)system connected to different AC voltage levels because of its ability to reduce the scale factor of a converter transformer.Faults in the HC-UHVDC system can cause commutation failure(CF).In this paper,impact of synchronous condenser(SC)to mitigate CF in HC-UHVDC system is analyzed.A±800KV HC-UHVDC system along with synchronous condenser is built in PSCAD/EMTDC.Transient performance analysis of HC-UHVDC for single and three phase to ground faults is investigated.Commutation failure immunity index(CFII),commutation failure probability index(CFPI),fault recovery time(FRT),and transient overvoltage(TOV)are used as measures to evaluate the effects of SC at HC-UHVDC system design.The simulation results show that SC can make the HCUHVDC system less susceptible to CF,effectively improve fault recovery performances of the overall system,and reduce transient overvoltage when single or multiple converters are blocked.The results of this research can provide technical assistance in real world HC-UHVDC projects.
