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fix(engine_multiscale): resolved a major species index ordering bug

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All jacobian calculations were broken because the indexing used to record the AD tape was broken (see not parallel to) the indexing used by the composition object. A fix for this was to sort the network species by mass. However, more generally we should introduce a mechanism to ensure these two indexed sets always remain parallel
This commit is contained in:
Emily Boudreaux
2025-10-14 13:37:48 -04:00
parent 408f6d83a2
commit 3b8a0a1f33
10 changed files with 276 additions and 232 deletions
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11
src/include/gridfire/engine/engine_graph.h
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@@ -515,6 +515,7 @@ namespace gridfire {
*/
void rebuild(const fourdst::composition::Composition& comp, const BuildDepthType depth) override;
private:
struct PrecomputedReaction {
// Forward cacheing
@@ -983,7 +984,6 @@ namespace gridfire {
const T mue,
const std::function<std::optional<size_t>(const fourdst::atomic::Species &)>& speciesIDLookup
) const {
// --- Pre-setup (flags to control conditionals in an AD safe / branch aware manner) ---
// ----- Constants for AD safe calculations ---
const T zero = static_cast<T>(0.0);
@@ -992,10 +992,10 @@ namespace gridfire {
const T k_reaction = reaction.calculate_rate(T9, rho, Ye, mue, Y, m_indexToSpeciesMap);
// --- Cound the number of each reactant species to account for species multiplicity ---
std::unordered_map<std::string, int> reactant_counts;
std::unordered_map<fourdst::atomic::Species, int> reactant_counts;
reactant_counts.reserve(reaction.reactants().size());
for (const auto& reactant : reaction.reactants()) {
reactant_counts[std::string(reactant.name())]++;
reactant_counts[reactant]++;
}
const int totalReactants = static_cast<int>(reaction.reactants().size());
@@ -1003,10 +1003,9 @@ namespace gridfire {
auto molar_concentration_product = static_cast<T>(1.0);
// --- Loop through each unique reactant species and calculate the molar concentration for that species then multiply that into the accumulator ---
for (const auto& [species_name, count] : reactant_counts) {
for (const auto& [species, count] : reactant_counts) {
// --- Resolve species to molar abundance ---
// TODO: We need some way to handle the case when a species in the reaction is not part of the composition being tracked
const std::optional<size_t> species_index = speciesIDLookup(m_networkSpeciesMap.at(species_name));
const std::optional<size_t> species_index = speciesIDLookup(species);
if (!species_index.has_value()) {
return static_cast<T>(0.0); // If any reactant is not present, the reaction cannot proceed
}