Hybrid Characteristics: 3D radiative transfer for parallel adaptive mesh refinement hydrodynamics
Hybrid Characteristics: 3D radiative transfer for parallel adaptive mesh refinement hydrodynamics
复制标题
混合特性：并行自适应网格细化流体动力学的 3D 辐射传输
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
G. Mellema
中科院分区：
文献类型：
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作者：
E. Rijkhorst;T. Plewa;A. Dubey;G. Mellema
收到* /接受*摘要。我们开发了一种三维辐射传递方法，专门用于平行自适应网格细化流体力学代码。这种新算法，我们称之为混合特征，引入了一种新的光线追踪形式，既不能被分类为长特征，也不能被分类为短特征，但它应用了基本原则，即通过插值和并行性有效执行。混合特性方法的主要应用是考虑了点源辐射引起的光电离和加热效应的辐射流体动力学问题。该方法在流体力学软件包FLASH中实现。电离、加热和冷却过程使用DORIC电离包进行建模。通过与长特征方法的比较，我们发现我们的方法以同样高的精度计算柱密度，并产生清晰而清晰的阴影。我们在多个过密团块的光蒸发应用中展示了新算法的质量。我们提出了几个测试问题，证明了我们的方法在大尺度范围内进行高分辨率三维辐射流体动力学计算的可行性。初始性能测试表明，我们方法的光线追踪部分比其他计算部分（例如流体力学和自适应网格细化）花费的时间更少，并且在并行执行中获得了很高的效率。虽然混合特性方法是针对点源引起的光电离问题而开发的，但该算法可以很容易地适用于更一般的辐射场。
Received * / Accepted * Abstract. We have developed a three-dimensional radiative transfer method designed specifically for use with parallel adaptive mesh refinement hydrodynamics codes. This new algorithm, wh ich we call hybrid characteristics, introduces a novel form of ray tracing that can neither be classified as long, nor as shor t characteristics, but which applies the underlying princi ples, i.e. efficient execution through interpolation and paralleliza bility, of both. Primary applications of the hybrid characteristics method are radiation hydrodynamics problems that take into account the effects of photoionization and heating due to point sources of radiation. The method is implemented in the hydrodynamics package FLASH. The ionization, heating, and cooling processes are modelled using the DORIC ionization package. Upon comparison with the long characteristics method, we find tha t our method calculates the column density with a similarly high accuracy and produces sharp and well defined shadows. We show the quality of the new algorithm in an application to the photoevaporation of multiple over-dense clumps. We present several test problems demonstrating the feasibility of our method for performing high resolution three-dimensional radiation hydrodynamics calculations that span a large range of scales. Initial performance tests show that the ray tra cing part of our method takes less time to execute than other parts of the calculation (e.g. hydrodynamics and adaptive mesh refinem ent), and that a high degree of efficiency is obtained in parallel ex ecution. Although the hybrid characteristics method is developed for problems involving photoionization due to point sources, the algorithm can be easily adapted to the case of more general radiation fields.