Optimization of theoretical pressure prediction model for confined explosion of low-carbon fuels.

A theoretical method was optimized based on a wrinkled flame model for predicting the explosion pressure in confined chambers for typical low-carbon fuels, e.g., hydrogen (H 2), methane (CH 4), and ammonia/dimethyl ether/hydrogen (NH 3 /DME/H 2) blends, etc. It was found that the previous model with a wrinkling factor of Ξ Δ = e t (t is time) is only applicable to the explosions of H 2 fuel, while considerably underestimating the explosion pressures of other fuels such as CH 4 and NH 3 /DME/H 2 blends. For H 2 fuel where the pressure power exponent β > 0, the effect of flame wrinkling on the laminar burning velocity S L is less significant compared to that of adiabatic compression, so that an underestimated wrinkling factor does not affect the overall prediction of pressure by the model. However, for most fuels with β < 0, a more accurate representation of the wrinkling effect is necessary for pressure prediction. The results show that the model can be optimized by increasing the wrinkling factor to Ξ Δ = e 20 t that satisfactorily represents the effect of flame instabilities. The wrinkling factor remains constant (Ξ Δ = 2.46) after it reaches its maximum value of 2.46. Comparison of the model predictions to experiments shows that the optimized model can well predict the explosion pressures of various low-carbon fuels that experienced flame instability. • The wrinkled flame model for predicting the explosion pressure in confined chambers was optimized. • For H 2 , the effect of flame wrinkling on flame speed is less significant compared to that of adiabatic compression. • For fuels with β < 0, the wrinkling factor was increased to Ξ Δ = e 20 t with the maximum value of 2.46. • The optimized model can well predict the explosion pressures of different fuels at various initial conditions. [ABSTRACT FROM AUTHOR]