A Heterogeneous Architecture for Evaluating Real-Time One-Dimensional Computational Fluid Dynamics on FPGAs

Many fuel systems for diesel engines are developed with the help of commercial one-dimensional computational fluid dynamics (1D CFD) solvers that model and simulate the behavior of fluid flow through the interconnected pipes off-line. This paper presents a novel framework to evaluate 1D CFD models in real time on an FPGA. This improves fuel pressure estimation and closes the loop on fuel delivery, allowing for a cleaner and more efficient engine. The real-time requirements of the models are defined by the physics and geometry of the problem being solved. In this framework, the interconnected pipes are partitioned into individual sub-volumes that compute their pressure and flow rate every time step based upon neighboring values. We use timing-based synchronization and multiple Precision Timed (PRET) processor cores to ensure the real-time constraints are met. Leveraging the programmability of FPGAs, we use a configurable heterogeneous architecture to save hardware resources. Several examples are presented along with the implementation results after place and route for a Xilinx Virtex 6 FPGA. The results demonstrate the resource savings and scalability of our framework, confirming the feasibility of our approach -- solving 1D CFD models in real time on FPGAs.