CHEMKIN-PRO

Reaction Path Analyzer

Understand which reactions most impact your results using CHEMKIN-PRO’s Reaction Path Analyzer. This powerful capability visualizes important information about the reactions that are taking place in the simulation. Details are provided on the forward and backward reaction rates and the absolute rates of production.

This understanding allows:

• Identification of dominant pathways
• Determination of pathways contributing to pollutant formation
• Determination of changes in pathways due to variation of operating conditions
• Guiding of mechanism reduction efforts
  
  

Particle Tracking Module

Tracking particles is important in many reacting flow applications. For example, soot particle formation and emissions are critical concerns for compliance with environmental regulations. The Particle Tracking function included in CHEMKIN-PRO simulates particle inception, growth and oxidation, providing statistics on particle sizes and mass loading. 

Features include:

• Sectional method that directly provides the details of particle size distributions
• Moment method that predicts the statistics of particle-size-distribution, such as mean particle diameter
• Prediction of mass and volume fractions of particles in the particle-flow system
• Initiation of particle-size tracking using a method that tracks the moments of the particle size distribution function when a dispersed condensed-phase material is encountered in the chemistry set
• Nucleation reaction type that models the formation of a condensed phase dispersed in the gas flow
• Ability to include nucleation from more than one particle precursor
• Ability to specify surface reactions for growth or reduction of particles due to condensation, deposition, oxidation, and any other surface reaction

Flame Extinction Model

Extinction is an important phenomenon in low-emissions combustion systems using staged combustion. Many designs operate near the edge of Lean Blow Off or lean extinction and it is important to understand how a design’s combustion stability is affected by local operating conditions and fuel/air ratios. CHEMKIN-PRO’s flame-extinction model provides an automated method for determining the flame-extinction strain rate for premixed flames in an opposed-flow flame configuration. The extinction strain rate is accurately determined through use of a continuation method. The calculation can be performed within a parameter study as well, to determine extinction strain rate as a function of conditions, such as fuel-air equivalence ratio.

Multi-Zone Engine Model

Transportation manufacturers are developing new combustion technologies to meet current and upcoming emissions regulations without performance compromises. Key attributes such as ignition, flame speed, and pollutant formation are governed by detailed chemistry behavior and the conditions in the cylinder. Many commercial Computational Fluid Dynamics (CFD) programs cannot support the level of detailed chemistry required to accurately simulate these combustion performance criteria. CHEMKIN-PRO’s Multi-Zone Engine Model segments the cylinder volume into reaction zones where detailed chemistry mechanisms can be applied efficiently while maintaining an accurate representation of the cylinder geometry.

The Multi-zone engine model enables:

• Investigation of ignition and flame speed through a transient solution
• Accurate emissions predictions for NOx, CO and UHC
• Investigation of Exhaust Gas recirculation impacts on the thermal NOx formation rate