The lean blowout experiments of the combustion stability device A (multi-vortexes-dome model combustor) have been carried out at atmospheric pressure. Compared with the device B (single-vortex-dome model combustor), t...The lean blowout experiments of the combustion stability device A (multi-vortexes-dome model combustor) have been carried out at atmospheric pressure. Compared with the device B (single-vortex-dome model combustor), the experimental results show that the device A has a superior lean blowout performance when the combustor reference velocity is within the range from 3.50m/s to 5.59m/s ( while the liner reference velocity is between 3.84 and 6.13m/s), and this superiority will remain stable after the inlet air flow rate reaches a certain value. In order to analyze the phenomena and experimental results, the numerical simulation method is used, and the strain rate and the cold reflux impact are employed to further explain the reason that causes the difference between the two devices' lean blowout characteristics.展开更多
Optical vortex is a promising candidate for capacity scaling in next-generation optical communications.The generation of multi-vortex beams is of great importance for vortex-based optical communications.Traditional ap...Optical vortex is a promising candidate for capacity scaling in next-generation optical communications.The generation of multi-vortex beams is of great importance for vortex-based optical communications.Traditional approaches for generating multivortex beams are passive,unscalable and cumbersome.Here,we propose and demonstrate a multi-vortex laser,an active approach for creating multi-vortex beams directly at the source.By printing a specially-designed concentric-rings pattern on the cavity mirror,multi-vortex beams are generated directly from the laser.Spatially,the generated multi-vortex beams are decomposable and coaxial.Temporally,the multi-vortex beams can be simultaneously self-mode-locked,and each vortex component carries pulses with GHz-level repetition rate.Utilizing these distinct spatial-temporal characteristics,we demonstrate that the multi-vortex laser can be spatially and temporally encoded for data transmission,showing the potential of the developed multi-vortex laser in optical communications.The demonstrations may open up new perspectives for diverse applications enabled by the multi-vortex laser.展开更多
基金supported by the National Natural Science Foundation of China (No. 50876104)the Major State Basic Research Development Scheme of China (No. 2012CB720406)
文摘The lean blowout experiments of the combustion stability device A (multi-vortexes-dome model combustor) have been carried out at atmospheric pressure. Compared with the device B (single-vortex-dome model combustor), the experimental results show that the device A has a superior lean blowout performance when the combustor reference velocity is within the range from 3.50m/s to 5.59m/s ( while the liner reference velocity is between 3.84 and 6.13m/s), and this superiority will remain stable after the inlet air flow rate reaches a certain value. In order to analyze the phenomena and experimental results, the numerical simulation method is used, and the strain rate and the cold reflux impact are employed to further explain the reason that causes the difference between the two devices' lean blowout characteristics.
基金supported by the National Natural Science Foundation of China Grant No.61675130,11774116,11721091,61490713,91850203,61761130082,11574001,the National Key R&D Program of China(2018YFB2200204,2018YFB1801803)the Royal Society-Newton Advanced Fellowship,the Natural Science Foundation of Hubei Province of China(2018CFA048)+2 种基金the Key R&D Program of Guangdong Province(2018B030325002)the Program for HUST Academic Frontier Youth Team(2016QYTD05)the Fundamental Research Funds for the Central Universities(2019kfyRCPY037).
文摘Optical vortex is a promising candidate for capacity scaling in next-generation optical communications.The generation of multi-vortex beams is of great importance for vortex-based optical communications.Traditional approaches for generating multivortex beams are passive,unscalable and cumbersome.Here,we propose and demonstrate a multi-vortex laser,an active approach for creating multi-vortex beams directly at the source.By printing a specially-designed concentric-rings pattern on the cavity mirror,multi-vortex beams are generated directly from the laser.Spatially,the generated multi-vortex beams are decomposable and coaxial.Temporally,the multi-vortex beams can be simultaneously self-mode-locked,and each vortex component carries pulses with GHz-level repetition rate.Utilizing these distinct spatial-temporal characteristics,we demonstrate that the multi-vortex laser can be spatially and temporally encoded for data transmission,showing the potential of the developed multi-vortex laser in optical communications.The demonstrations may open up new perspectives for diverse applications enabled by the multi-vortex laser.