From 72669aacd720690fecbbd40dd6a6447d73cdba67 Mon Sep 17 00:00:00 2001 From: Joshua Christopher Date: Wed, 11 Dec 2024 16:18:32 -0500 Subject: [PATCH] Fixed documentation of activation energy in LL surface growth rate. I believe the activation energy of 21100 in the growth rate is incorrect based on the cited paper (Leung et al. 1991, "A simplified reaction mechanism for soot formation in nonpremixed flames"). I believe the activation energy should be 12100. The code implementation in src/growthModels/growthModel_LL.cc has an activation energy of 12100 and looks correct to me, so this is merely a documentation typo. --- docs/models/1_chemistry.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/docs/models/1_chemistry.md b/docs/models/1_chemistry.md index f276c81..7dae37f 100644 --- a/docs/models/1_chemistry.md +++ b/docs/models/1_chemistry.md @@ -84,7 +84,7 @@ Most soot surface growth models rely on acetylene (\f$\text{C}_2\text{H}_2\f$) a ### Leung & Lindstedt (LL) The Leung and Lindstedt mechanism for soot surface growth (LL) \cite Leung_1991 depends on both the gaseous concentration of acetylene and the particle surface area available for surface reactions. The overall rate of soot surface growth is computed as -$$R_{grw} = 0.6\times 10^4 e^{-21100/T} f(A_s) [\text{C}_2\text{H}_2].$$ +$$R_{grw} = 0.6\times 10^4 e^{-12100/T} f(A_s) [\text{C}_2\text{H}_2].$$ \f$f(A_s)\f$ is a function of the available particle surface area given by $$f(A_s) = \sqrt{\pi \left( \frac{6MW_C}{\pi \rho_{s}} \right) ^{2/3}} \left[ \frac{\rho Y_{s}}{MW_C} \right]^{1/3} [\rho N]^{1/6},$$ where \f$MW_{\text{C}}\f$ is the molar mass of carbon, \f$\rho\f$ is the gas density, \f$\rho_{s}\f$ is the solid density of soot, \f$Y_{s}\f$ is the mass fraction of soot, and \f$N\f$ is the soot particle number density. Results showed that the normal square dependence of the rate on available surface sites does not accurately predict the soot number density throughout the flame \cite Leung_1991, and later models explored alternative methods.