  An integrated computational framework is introduced to study complex
engineering systems through physics-based ensemble simulations on heterogeneous
supercomputers. The framework is primarily designed for the quantitative
assessment of laser-induced ignition in rocket engines. We develop and combine
an implicit programming system, a compressible reacting flow solver, and a data
generation/management strategy on a robust and portable platform. We
systematically present this framework using test problems on a hybrid CPU/GPU
machine. Efficiency, scalability, and accuracy of the solver are
comprehensively assessed with canonical unit problems. Ensemble data management
and autoencoding are demonstrated using a canonical diffusion flame case.
Sensitivity analysis of the ignition of a turbulent, gaseous fuel jet is
performed using a simplified, three-dimensional model combustor. Our approach
unifies computer science, physics and engineering, and data science to realize
a cross-disciplinary workflow. The framework is exascale-oriented and can be
considered a benchmark for future computational science studies of real-world
systems.
