XFLUIDS: A SYCL-based unified cross-architecture heterogeneous simulation solver for compressible reacting flows

We present a cross-architecture high-order heterogeneous Navier-Stokes simulation solver, XFluids, for compressible reacting multicomponent flows on different platforms. The multi-component reacting flows are ubiquitous in many scientific and engineering applications, while their numerical simulations are usually time-consuming to capture the underlying multiscale features. Although heterogeneous accelerated computing is significantly beneficial for large-scale simulations of these flows, effective utilization of various heterogeneous accelerators with different architectures and programming models in the market remains a challenge. To address this, we develop XFluids by SYCL, to perform acceleration directly targeted to different devices, without translating any source code. A variety of optimization techniques have been proposed to increase the computational performance of XFluids, including adaptive range assignment, partial eigensystem reconstruction, hotspot device function optimizations, etc. This solver has been open-sourced, and tested on multiple GPUs from different mainstream vendors, indicating high portability. Through various benchmark cases, the accuracy of XFluids is demonstrated, with approximately no efficiency loss compared to existing GPU programming models, such as CUDA and HIP. In addition, the MPI library is used to extend the solver to multi-GPU platforms, with the GPU-enabled MPI supported. With this, the weak scaling of XFluids for multi-GPU devices is larger than 95% for 1024 GPUs. Finally, we simulate both the inert and reactive multicomponent shock-bubble interaction problems with high-resolution meshes, to investigate the reacting effects on the mixing, vortex stretching, and shape deformation of the bubble evolution.