论文标题
Cuharm：新的GPU加速GR-MHD代码及其在ADAF磁盘上的应用
cuHARM : a new GPU accelerated GR-MHD code and its application to ADAF disks
论文作者
论文摘要
我们根据我们称为Cuharm的伤害，引入了新的GPU加速通用磁动力（GR-MHD）代码。该代码用CUDA-C编写，并使用OpenMP并行化多GPU设置。我们的代码允许我们在不需要多节点超级计算机基础结构的情况下运行积聚磁盘的高分辨率模拟以及喷气机的形成和结构。 $ 256^3 $仿真在NVIDIA DGX-V100服务器的范围内，如果仅使用CPU，则计算的速度约为10倍。我们使用此代码检查所有处于理智状态的磁盘结构。我们发现：（i）增加磁场，而在理智状态下不影响质量吸积率； （ii）同时增加磁盘尺寸和磁场，同时保持固定的能量之比，一旦磁通量通过地平线降低到一定极限以下。这表明射流的存在不是初始磁场强度的线性函数。 （iii）射流的结构是气体绝热指数的弱功能，具有相对论气体倾向于具有更大的射流。
We introduce a new GPU-accelerated general-relativistic magneto-hydrodynamic (GR-MHD) code based on HARM which we call cuHARM. The code is written in CUDA-C and uses OpenMP to parallelize multi-GPU setups. Our code allows us to run high resolution simulations of accretion disks and the formation and structure of jets without the need of multi-node supercomputer infrastructure. A $256^3$ simulation is well within the reach of an Nvidia DGX-V100 server, with the computation being a factor about 10 times faster if only the CPU was used. We use this code to examine several disk structures all in the SANE state. We find that: (i) increasing the magnetic field, while in the SANE state does not affect the mass accretion rate; (ii) Simultaneous increase of the disk size and the magnetic field, while keeping the ratio of energies fixed, lead to the destruction of the jet once the magnetic flux through the horizon decrease below a certain limit. This demonstrates that the existence of the jet is not a linear function of the initial magnetic field strength; (iii) the structure of the jet is a weak function of the adiabatic index of the gas, with relativistic gas tend to have a wider jet.
