To achieve real-time control of tokamak plasmas, the equilibrium reconstruction has to be completed sufficiently quickly. For the case of an EAST tokamak experiment, real-time equilibrium reconstruction is generally r...To achieve real-time control of tokamak plasmas, the equilibrium reconstruction has to be completed sufficiently quickly. For the case of an EAST tokamak experiment, real-time equilibrium reconstruction is generally required to provide results within 1ms. A graphic processing unit(GPU) parallel Grad–Shafranov(G-S) solver is developed in P-EFIT code,which is built with the CUDA? architecture to take advantage of massively parallel GPU cores and significantly accelerate the computation. Optimization and implementation of numerical algorithms for a block tri-diagonal linear system are presented. The solver can complete a calculation within 16 μs with 65×65 grid size and 27 μs with 129×129 grid size, and this solver supports that P-EFIT can fulfill the time feasibility for real-time plasma control with both grid sizes.展开更多
The ionization time in sequential double ionization with an elliptically polarized laser pulse has been examined theo- retically using a semiclassical method. The significant discrepancy between the ionization time fo...The ionization time in sequential double ionization with an elliptically polarized laser pulse has been examined theo- retically using a semiclassical method. The significant discrepancy between the ionization time for parallel and anti-parallel electron emission is predicted numerically for the first time. The impact of the carrier envelope phase offset is also studied in this work.展开更多
基金supported by the National Magnetic Confinement Fusion Research Program of China(Grant No.2014GB103000)the National Natural Science Foundation of China(Grant No.11575245)the National Natural Science Foundation of China for Youth(Grant No.11205191)
文摘To achieve real-time control of tokamak plasmas, the equilibrium reconstruction has to be completed sufficiently quickly. For the case of an EAST tokamak experiment, real-time equilibrium reconstruction is generally required to provide results within 1ms. A graphic processing unit(GPU) parallel Grad–Shafranov(G-S) solver is developed in P-EFIT code,which is built with the CUDA? architecture to take advantage of massively parallel GPU cores and significantly accelerate the computation. Optimization and implementation of numerical algorithms for a block tri-diagonal linear system are presented. The solver can complete a calculation within 16 μs with 65×65 grid size and 27 μs with 129×129 grid size, and this solver supports that P-EFIT can fulfill the time feasibility for real-time plasma control with both grid sizes.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11135002, 11075069, 91026021, 11075068, and 10975065)the Fundamental Research Funds for the Central Universities of China (Grant No. lzujbky-2010-k08)the Scholarship Award for Excellent Doctoral Student granted by Ministry of Education
文摘The ionization time in sequential double ionization with an elliptically polarized laser pulse has been examined theo- retically using a semiclassical method. The significant discrepancy between the ionization time for parallel and anti-parallel electron emission is predicted numerically for the first time. The impact of the carrier envelope phase offset is also studied in this work.