# GFIS Research Scenario Experiments Generated at: 2026-05-05T18:23:21.834539+00:00 Hours per case: `48` ## Purpose These experiments evaluate GFIS under controlled anaerobic-digestion operating conditions rather than only under a nominal point prediction. Each case exercises a different dissertation-relevant behavior: methane-yield response, soft-sensor stability warning, and physics-bound feasibility checking. ## Scenario Summary | Scenario | Mean methane yield | Max VFA/ALK | Final stability | Warning/Critical hours | Physics violation hours | | --- | ---: | ---: | --- | ---: | ---: | | Nominal mesophilic operation | 199.342 | 0.197 | Stable | 0 | 0 | | Organic overload | 200.932 | 0.335 | Warning | 48 | 0 | | pH acidification shock | 152.935 | 0.284 | Stable | 0 | 0 | | Low-temperature disturbance | 183.397 | 0.227 | Stable | 0 | 0 | | Reduced HRT washout risk | 194.579 | 0.278 | Stable | 0 | 0 | | High-solids feedstock | 213.273 | 0.251 | Stable | 0 | 0 | | Corrective recovery operation | 196.719 | 0.152 | Stable | 0 | 0 | ## Case Notes ### Nominal mesophilic operation Research purpose: Reference condition for stable methane production. - Point methane yield: `199.941` - Point VFA/ALK: `0.189` - Point stability: `Stable` - 48h mean methane yield: `199.342` - 48h maximum VFA/ALK: `0.197` - Warning/Critical hours: `0` - Physics violation hours: `0` ### Organic overload Research purpose: Tests whether the soft sensor detects rising VFA/ALK risk under high organic loading. - Point methane yield: `201.86` - Point VFA/ALK: `0.331` - Point stability: `Warning` - 48h mean methane yield: `200.932` - 48h maximum VFA/ALK: `0.335` - Warning/Critical hours: `48` - Physics violation hours: `0` ### pH acidification shock Research purpose: Simulates acidification stress and checks whether methane prediction remains physics-bounded. - Point methane yield: `168.845` - Point VFA/ALK: `0.272` - Point stability: `Stable` - 48h mean methane yield: `152.935` - 48h maximum VFA/ALK: `0.284` - Warning/Critical hours: `0` - Physics violation hours: `0` ### Low-temperature disturbance Research purpose: Tests loss of mesophilic efficiency during a thermal disturbance. - Point methane yield: `182.792` - Point VFA/ALK: `0.219` - Point stability: `Stable` - 48h mean methane yield: `183.397` - 48h maximum VFA/ALK: `0.227` - Warning/Critical hours: `0` - Physics violation hours: `0` ### Reduced HRT washout risk Research purpose: Represents short retention time and potential biomass washout risk. - Point methane yield: `181.19` - Point VFA/ALK: `0.261` - Point stability: `Stable` - 48h mean methane yield: `194.579` - 48h maximum VFA/ALK: `0.278` - Warning/Critical hours: `0` - Physics violation hours: `0` ### High-solids feedstock Research purpose: Tests high TS/VS operation and the volatile-solids methane upper-bound layer. - Point methane yield: `211.753` - Point VFA/ALK: `0.236` - Point stability: `Stable` - 48h mean methane yield: `213.273` - 48h maximum VFA/ALK: `0.251` - Warning/Critical hours: `0` - Physics violation hours: `0` ### Corrective recovery operation Research purpose: Tests an operator intervention with lower OLR, higher HRT, and near-neutral pH. - Point methane yield: `196.944` - Point VFA/ALK: `0.15` - Point stability: `Stable` - 48h mean methane yield: `196.719` - 48h maximum VFA/ALK: `0.152` - Warning/Critical hours: `0` - Physics violation hours: `0` ## Dissertation Interpretation The experiments support the dissertation claim that GFIS is an operational decision-support digital twin. The system does not only return methane-yield estimates; it evaluates process stability, applies a physics feasibility layer, logs simulation runs, and gives a structured basis for comparing normal operation, overload, disturbance, and corrective action. Current limitation: these runs use a synthetic anaerobic-digestion dataset. Final dissertation text should state this clearly and position the system as a deployable research prototype that can be recalibrated with plant or public experimental data.