From dfd9bc2c94ba6b2565678ca6fc70716d525e3403 Mon Sep 17 00:00:00 2001 From: Harry Moffat Date: Tue, 29 Dec 2009 00:00:37 +0000 Subject: [PATCH] Added a reaction to the mechanism to promote numerical stability. Added a unimolecular dissociation rxn to avoid singular jacobians. --- data/inputs/ptcombust.cti | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/data/inputs/ptcombust.cti b/data/inputs/ptcombust.cti index 43154883c..ef9c6b5ed 100644 --- a/data/inputs/ptcombust.cti +++ b/data/inputs/ptcombust.cti @@ -290,3 +290,11 @@ surface_reaction( "C(S) + O(S) => CO(S) + PT(S)", [3.70000E+21, 0, 62800]) # Reaction 24 surface_reaction( "CO(S) + PT(S) => C(S) + O(S)", [1.00000E+18, 0, 184000]) + +# Reaction 25 (12/28/2009 HKM added: This is a fictious rxn that is added for numerical stability. +# The issue is that if multiple surface species have a negative concentration, the +# Jacobian for the surface problem will go singular due to the way negative concentrations +# are truncated within Cantera. Adding in unimolecular desorption rxns with neglibigle real +# effects alleviates the problem.) +surface_reaction( "C(S) => C + PT(S)", [3.7E7, 0, 62800]) +