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An indicator-based problem reduction scheme for coupled reactive transport models.

ABSTRACT: A number of effective models have been developed for simulating chemical transport in porous media; however, when a reactive chemical problem comprises multiple species within a substantial domain for a long period of time, the computational cost can become prohibitively expensive. This issue is addressed here by proposing a new numerical procedure to reduce the number of transport equations to be solved. This new problem reduction scheme (PRS) uses a predictor-corrector approach, which "predicts" the transport of a set of non-indicator species using results from a set of indicator species before "correcting" the non-indicator concentrations using a mass balance error measure. The full chemical transport model is described along with experimental validation. The PRS is then presented together with an investigation, based on a 16-species reaction-advection-diffusion problem, which determines the range of applicability of different orders of the PRS. The results of a further study are presented, in which a set of PRS simulations is compared with those from full model predictions. The application of the scheme to the intermediate-sized problems considered in the present study showed reductions of up to 82% in CPU time, with good levels of accuracy maintained.

SUBMITTER: Freeman BL

PROVIDER: S-EPMC7167707 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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An indicator-based problem reduction scheme for coupled reactive transport models.

Freeman Brubeck Lee BL Cleall Peter John PJ Jefferson Anthony Duncan AD

International journal for numerical methods in engineering 20190827 13

A number of effective models have been developed for simulating chemical transport in porous media; however, when a reactive chemical problem comprises multiple species within a substantial domain for a long period of time, the computational cost can become prohibitively expensive. This issue is addressed here by proposing a new numerical procedure to reduce the number of transport equations to be solved. This new problem reduction scheme (PRS) uses a predictor-corrector approach, which "predict ...[more]

PMID: 32327811

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Dataset Information

An indicator-based problem reduction scheme for coupled reactive transport models.

Publications

An indicator-based problem reduction scheme for coupled reactive transport models.

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