Global warming caused by the use of fossil fuels is a common concern of the world today.It is of practical importance to conduct in-depth fundamental research and optimal design for modern engine combustors through Ho...Global warming caused by the use of fossil fuels is a common concern of the world today.It is of practical importance to conduct in-depth fundamental research and optimal design for modern engine combustors through However,complex hydrocarbon chemistry,an indispensable component for predictive modeling,is computahigh-fidelity computational fluid dynamics(CFD),so as to achieve energy conservation and emission reduction.tionally demanding,Its application in simulation-based design optimization,although desirable,is quite limited.To address this challenge,we propose a methodology for representing complex chemistry with artificial neural networks(ANNs),which are trained with a comprehensive sample dataset generated by the Latin hypercube sampling(LHS)method.With a given chemical kinetic mechanism,the thermochemical sample data is able to cover the whole accessible pressure/temperature/species space in various turbulent flames.The ANN-based model consists of two different layers:the self-organizing map(SOM)and the back-propagation neural network(BPNN).The methodology is demonstrated to represent a 30-species methane chemical mechanism.The obtained ANN model is applied to simulate both a non-premixed turbulent flame(DLR_A)and a partially premixed turbulent flame(Flame D)to validate its applicability for different flames.Results show that the ANN-based chemical kinetics can reduce the computational cost by about two orders of magnitude without loss of accuracy,The proposed methodology can successfully construct an ANN-based chemical mechanism with significant ffciency gain and a broad scope of applicability,and thus holds a great potential for complex hydrocarbon fuels.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.52025062)Simulations are performed with the computational resources from the Tsinghua National Laboratory for Information Science and Technology.
文摘Global warming caused by the use of fossil fuels is a common concern of the world today.It is of practical importance to conduct in-depth fundamental research and optimal design for modern engine combustors through However,complex hydrocarbon chemistry,an indispensable component for predictive modeling,is computahigh-fidelity computational fluid dynamics(CFD),so as to achieve energy conservation and emission reduction.tionally demanding,Its application in simulation-based design optimization,although desirable,is quite limited.To address this challenge,we propose a methodology for representing complex chemistry with artificial neural networks(ANNs),which are trained with a comprehensive sample dataset generated by the Latin hypercube sampling(LHS)method.With a given chemical kinetic mechanism,the thermochemical sample data is able to cover the whole accessible pressure/temperature/species space in various turbulent flames.The ANN-based model consists of two different layers:the self-organizing map(SOM)and the back-propagation neural network(BPNN).The methodology is demonstrated to represent a 30-species methane chemical mechanism.The obtained ANN model is applied to simulate both a non-premixed turbulent flame(DLR_A)and a partially premixed turbulent flame(Flame D)to validate its applicability for different flames.Results show that the ANN-based chemical kinetics can reduce the computational cost by about two orders of magnitude without loss of accuracy,The proposed methodology can successfully construct an ANN-based chemical mechanism with significant ffciency gain and a broad scope of applicability,and thus holds a great potential for complex hydrocarbon fuels.
