Detailed chemistry computations are indispensable in
numerous complex
simulation tasks, which focus on accurately capturing the ignition
process or predicting pollutant levels. The machine learning method
is a modern data-driven approach for predicting a full detailed thermochemical
state-to-state behavior in reacting flow simulations. By combining
unsupervised clustering algorithms to subdivide the composition space,
the complexity of adaptive regression models for temporal dynamics
can be significantly reduced. In this article, a more compact dataset
is generated, which is essential for the clustering algorithm, by
leveraging the adaptive CVODE solver time steps for data augmentation
for stiff reactive states. A learning workflow that utilizes a deep
residual network model (ResNet) in conjunction with an adaptive clustering
algorithm is proposed. This approach aims to replace the stiff ordinary
differential equation direct integration solver traditionally used
for computing thermochemical species’ state-to-state temporal
evolution for detailed chemistry simulations. The learning models
are adaptively trained using the K-means clustering algorithm in the
non-linear transformation space for different subspaces of dynamic
systems. Three test cases, H2 (9 species), C2H4 (32 species), and CH4 (53 species), are
investigated, each exhibiting varying complexities. The study demonstrates
that the iterative predictions of thermochemical states align well
with the results obtained from direct numerical integration. Additionally,
employing multiple adaptive regression models in subdomains yields
superior performance compared to a single regression model prediction
case.