COMPUTATIONAL THERMO-FLUID DYNAMICS MODELING FOR PROCESS OPTIMIZATION IN HYDROGEN-INTEGRATED INDUSTRIAL HEAT SYSTEMS

Abstract

This study evaluated computational thermo-fluid dynamics modeling as a quantitative platform for process optimization in hydrogen-integrated industrial heat systems. A validated three-dimensional reacting CFD model was executed as a controlled numerical experiment across 60 design-of-experiments cases that spanned hydrogen volumetric shares from 0% to 100% (mean 52.3%, SD 30.1), oxidizer staging ratios from 0.50 to 0.90 (mean 0.70), swirl/mixing levels from 0.20 to 0.90 (mean 0.56), jet momentum ratios from 0.60 to 1.80 (mean 1.12), and recirculation rates from 0% to 25% (mean 11.8%). Extracted responses showed practical but non-uniform hydrogen effects: useful heat-transfer efficiency ranged from 71.2% to 86.5% (mean 79.8%, SD 4.1), load temperature spread increased markedly from 18.4°C to 72.9°C (mean 41.6°C, SD 13.8), peak wall temperature varied between 1125°C and 1328°C (mean 1224°C), chamber pressure drop rose from 185 to 412 Pa (mean 298 Pa), and NOx emission index spanned 0.38 to 1.54 g/MJ (mean 0.92 g/MJ). Correlation screening indicated strong positive associations between hydrogen share and NOx (r = 0.61), peak wall temperature (r = 0.52), and temperature spread (r = 0.47), while the link to efficiency was weak (r = 0.18). Reliability checks showed repeatability differences below 3% for all indicators and medium–fine mesh differences below 3.1%, confirming numerical stability. Multivariate regressions revealed that hydrogen share significantly increased NOx, wall hot spots, non-uniformity, and pressure drop, whereas oxidizer staging and swirl significantly mitigated these penalties; the hydrogen–staging interaction produced the largest NOx suppression. Feasible operating windows were therefore characterized by moderate-to-high hydrogen shares combined with elevated staging and swirl, preserving efficiency while meeting emissions, stability, pressure-loss, and material-temperature constraints.