The article addresses the implications of adopting (a) non-kinetic theory-based correlations for the estimation of thermodynamic and transport properties and (b) over-simplifying assumptions, as reported in literature, in the numerical simulation of thermo-chemical conversion of char. A one-dimensional char thermo-chemical conversion model with discretisation to capture intra-particle gradients of temperature and species is developed. Species and mixture property estimations are based on kinetic theory approaches, and all extraneous assumptions are eliminated. Simulation results indicate char conversion in air and ${\mathrm{C}\mathrm{O}}_2$ to be near diffusion $(t_c\sim d_0^{1.8})$ and near kinetic $(t_c\sim d_0^{1.05})$ limit, respectively, while char conversion in ${\mathrm{H}}_2\mathrm{O}$ has a competitive influence of both diffusion and kinetics $(t_c\sim d_0^{1.35})$. Literature-specific correlations yield an order of magnitude deviation (up to 800%) in the properties (thermal conductivity, specific heat, mass diffusivity). Adopting mole/mass fraction weighted averaging for mixture transport properties results in variations to the extent of 85%. Unity Lewis number assumption introduces one order magnitude deviation in presence of ${\mathrm{H}}_2$. It is observed that the deviations introduced in conversion process can be surmounted by using correction factor in the kinetic rate parameters, a prevalent practice. Such an approach is however thermodynamically untenable.

本文讨论了采用 (a) 基于非动力学理论的相关性来估计热力学和输运性质的影响和 (b) 过度简化假设的影响，如文献中报道的那样，在炭热化学转化的数值模拟中. 开发了一种具有离散化的一维炭热化学转化模型，以捕获温度和物种的颗粒内梯度。物种和混合物特性估计基于动力学理论方法，并且消除了所有无关假设。模拟结果表明在空气和${\mathrm{C}\mathrm{哦}}_2$ 接近扩散 $({吨}_C～d_0^{1.8})$ 和接近动力学 $({吨}_C～d_0^{1.05})$ 分别限制，而 char 转换中 ${\mathrm{H}}_2\mathrm{哦}$ 具有扩散和动力学的竞争影响 $({吨}_C～d_0^{1.35})$. 特定于文献的相关性在属性（热导率、比热、质量扩散率）方面产生一个数量级的偏差（高达 800%）。采用摩尔/质量分数加权平均的混合物输运性质会导致 85% 的变化。Unity Lewis 数假设在存在以下情况时引入了一个数量级的偏差${\mathrm{H}}_2$. 据观察，转化过程中引入的偏差可以通过在动力学速率参数中使用校正因子来克服，这是一种普遍的做法。然而，这种方法在热力学上是站不住脚的。