Non-Premixed Combustion Non-Adiabatic Chemical Equilibrium CFD Simulation

Non-Premixed Combustion, Non-Adiabatic, Chemical Equilibrium, ANSYS Fluent CFD Training

Welcome to the third episode of our comprehensive “Combustion: All Levels” course. In this advanced lesson, we dive deep into the intricacies of non-premixed, non-adiabatic combustion simulation using ANSYS Fluent software. This episode focuses on chemical equilibrium modeling and provides valuable insights into real-world combustion scenarios.

Simulation Overview

Our simulation centers on a two-dimensional combustion chamber model, where we’ll investigate non-premixed combustion dynamics under non-adiabatic conditions. This episode aims to provide a thorough understanding of the complex interactions between fuel and air when introduced separately into the combustion chamber.

Model Geometry and Meshing

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

• Geometry designed using Design Modeler software for precision
• Meshing performed with ANSYS Meshing software
• Structured mesh type for optimal accuracy
• 63,280 elements ensuring detailed results and high-resolution analysis

This meticulous setup ensures that our simulation captures the nuances of the non-premixed combustion process with high fidelity.

Simulation Methodology

Non-Premixed Combustion Model

We employ the Non-Premixed Combustion model to simulate the combustion process effectively:

• Non-adiabatic energy treatment for realistic heat transfer modeling
• Chemical equilibrium approach for accurate species prediction
• Separate fuel and air inlets to simulate real-world combustion chambers

This approach allows for a comprehensive analysis of the complex mixing and reaction processes occurring during non-premixed combustion.

Probability Density Function (PDF) Table

A key component of our simulation is the pre-generated PDF table:

• Stores data on temperature variations, mixture density, and species mass fractions
• Enhances computational efficiency during main calculations
• Provides a robust framework for chemical equilibrium modeling

Additional Settings

To ensure a comprehensive simulation, we also:

• Enable the Energy equation to track temperature changes accurately
• 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
• Streamlines revealing flow patterns and mixing zones

These results will provide valuable insights into:

• The progression of combustion in a non-premixed environment
• Temperature evolution due to non-adiabatic conditions
• Species formation and consumption patterns
• The role of secondary flows in enhancing mixing and combustion

Learning Outcomes and Applications

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

• Advanced understanding of non-premixed, non-adiabatic combustion simulation techniques
• Insights into chemical equilibrium modeling in CFD
• Skills to interpret CFD results for complex combustion systems
• Knowledge of how secondary flows impact mixing and combustion efficiency

These skills are directly applicable to:

• Designing more efficient industrial furnaces and combustors
• Optimizing fuel injection systems in gas turbines
• Improving combustion chamber designs for reduced emissions
• Advancing research in non-premixed combustion phenomena

Join us in this cutting-edge exploration of non-premixed, non-adiabatic combustion simulation using ANSYS Fluent, and elevate your CFD expertise to new heights in combustion modeling!