Process and Computational Fluid Dynamics Studies

This chapter presents a comprehensive methodology for the design and evaluation of polygeneration systems, integrating steady-state, dynamic, and CFD simulations to optimise system performance, control strategies, and component design. The methodology begins with plant configuration, establishing process flow diagrams based on fuel sources (e.g., fossil or renewable), targeted services (e.g., electricity, heat, or chemicals), and thermodynamic cycles (e.g., steam Rankine or Kalina cycles). Steady-state simulations assess energy and exergy performance, subsystem integration, and overall plant efficiency, while dynamic simulations evaluate transient behaviour, operational flexibility, control strategies, and component lifetimes. CFD analyses focus on critical components such as combustion chambers, gasifiers, and cyclones, providing detailed insights into heat and mass transfer, pressure losses, combustion efficiency, pollutant formation, and potential material degradation. Process improvement is achieved iteratively by coupling simulation results with optimisation algorithms such as genetic algorithms, mixed-integer linear programming, and particle swarm optimisation. Finally, techno-economic, environmental, and social assessments are conducted to ensure the plant design is efficient, sustainable, cost-effective, and socially responsible. The chapter also summarises relevant literature on numerical simulations of polygeneration systems and provides an overview of widely used commercial and in-house simulation software.