Simulation of hydrogen dispersion by the domain decomposition method

Abstract

We demonstrate the feasibility of the domain decomposition method in simulating large scale finite element models through the ADVENTURE code, an open source freeware partly developed by the Computational Mechanics Laboratory at Kyushu University. Our model is that of hydrogen dispersion in a partially open space, chosen because of its relevance to the safe use of hydrogen as a potential replacement for fossil fuels. An analogy of the Boussinesq approximation is applied in our simulation. We describe the formulations and the model, followed by some results.

Numerical Simulation of the Hydrogen Dispersion Behavior by a Parallel Characteristic Curve Method

“…Around the inlet and the door, the flow field is complicated and oscillations are also viewed at sensor 1 and sensor 4. Compared with numerical results in [13,14], the current numerical results are more stable and closer to the experimental data and thus are more reliable.…”

“…To handle the problem caused by the nonlinear convective terms of flow problems, which result in the nonsymmetry of the stiffness matrix, a parallelized characteristic curve method for the domain decomposition method is used in this work. Compared with the traditional fashion is to employ some product-type methods as the iteration solver [14], the symmetry of the matrix enables computation problems with up to 30 million degrees of freedom (DOF) which can be solved [15]. In order to validate the solvability of dispersion behavior of hydrogen, the current computation results are compared with experimental results reported by Inoue et al [12].…”

“…Over the last few decades, much research has been done on the evaluation of leak flow rate [8], dispersion behavior in residential areas [9], and the design of ventilation systems of hydrogen dispersion [10,11]. Inoue et al report the experimental data of a ventilation model [12]; Kanayama et al report a numerical simulation to it by finite element method [13,14]; however, the numerical results contain obvious oscillations and the maximum value of concentration is even higher than the value concentration at the inlet, which are contradicted with the experimental data and prevent it from being a better simulation.…”

Large Scale Simulation of Hydrogen Dispersion by a Stabilized Balancing Domain Decomposition Method

“…On hydrogen dispersion problems, the evaluation of leak flow rate [3], the dispersion behaviour in residential areas [4], and the design of ventilation systems [5,6] have been reported. Inoue et al report the experimental data of a ventilation model [7], and Kanayama et al report a numerical simulation to it by finite element method [1,8]; however, the numerical results contain obvious oscillations which prevent it to be a better simulation. Because of the computation complexity of high Rayleigh number in the modelling hydrogen dispersion, conventional numerical simulation methods suffer from low convergence speed, poor stability, and robustness [9,10].…”

“…A variation of balancing domain decomposition is proposed and the efficiency is reported for simulation of hydrogen dispersion in this work. Compared with the traditional fashion of employing some product-type methods as the iteration solver [8], computation problems with up to 30 million degrees of freedom (DOF) can be solved on small Linux clusters by using the balancing domain decomposition [19]. In order to validate the solvability of dispersion behavior of hydrogen, the current computation results are compared with experimental results reported by Inoue et al [7].…”