Premixed Combustion for Pollution Formation CFD Simulation

Premixed Combustion (Eddy Dissipation/Finite Rate Model) for Pollution Formation CFD Simulation

Welcome to the fourth episode of our “Combustion: All Levels” course. In this advanced lesson, we’ll explore the intricacies of premixed combustion simulation using ANSYS Fluent software, with a focus on pollution formation. This episode builds upon previous knowledge and introduces the combined Eddy Dissipation/Finite Rate model for a more comprehensive analysis.

Simulation Overview

Our simulation focuses on a two-dimensional combustion chamber model, where we’ll investigate premixed combustion dynamics and their impact on pollution formation. We’ll use cutting-edge CFD techniques to provide insights into real-world combustion scenarios.

Model Setup and Meshing

The foundation of our simulation lies in a carefully crafted model:

• Geometry designed using Design Modeler software
• Meshing performed with ANSYS Meshing software
• Structured mesh type for optimal accuracy
• 86,002 elements ensuring detailed results

This meticulous setup ensures that our simulation captures the nuances of the combustion process.

Simulation Methodology

Species Transport Model

We employ the Species Transport model to simulate the combustion process effectively:

• One-reaction methane-air mixture for simplicity and clarity
• Volumetric option to model combustion throughout the chamber

Eddy Dissipation/Finite Rate Model

The core of our simulation lies in the Eddy Dissipation/Finite Rate model:

• Accounts for turbulence-chemistry interactions
• Balances mixing effects with reaction rates
• Provides insights into pollution formation mechanisms

This advanced model allows us to capture both mixing-limited and kinetically-limited aspects of the combustion process.

Additional Settings

To ensure a comprehensive simulation, we also:

• Enable the Energy equation to track temperature changes
• Utilize the Standard k-epsilon model for turbulence modeling

Results and Analysis

Upon completion of the simulation, we’ll analyze a range of outputs:

• Temperature distribution contours
• Velocity profiles throughout the chamber
• Mass fractions of various species, including pollutants
• Streamlines revealing secondary flow patterns

These results will provide valuable insights into:

• Combustion efficiency and completeness
• Pollutant formation zones and mechanisms
• The role of secondary flows in mixing and combustion enhancement

Learning Outcomes and Applications

By the end of this episode, you’ll have gained:

• Advanced understanding of premixed combustion simulation techniques
• Insights into the Eddy Dissipation/Finite Rate model and its advantages
• Skills to interpret CFD results for pollution formation analysis
• Knowledge of how secondary flows impact combustion and pollution

These skills are directly applicable to:

• Designing cleaner combustion systems
• Optimizing existing combustion chambers for reduced emissions
• Predicting and mitigating pollution in industrial processes

Join us in this cutting-edge exploration of premixed combustion and pollution formation simulation, and take your CFD expertise to new heights!