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Prediction of Heat Transfer and Fluid Flow Effects on Entropy Generation in a Monolithic Catalytic Converter Using
Yongxiang Li1,2, Luis Felipe Rico Cortes1,2, Hardy Hamel1
1Reactive Flows and Diagnostics, Technical University of Darmstadt, 64287 Darmstadt, Germany.
Entropy (Basel, Switzerland)
|May 28, 2022
Summary
This study examines heat transfer, fluid flow, and entropy generation in a Lada Niva catalytic converter using large eddy simulation. Results reveal flow patterns and dominant entropy production mechanisms within the converter under engine conditions.
Area of Science:
- Automotive Engineering
- Thermodynamics
- Computational Fluid Dynamics
Background:
- Catalytic converters are crucial for vehicle emissions control.
- Understanding internal heat transfer and fluid dynamics is key to optimizing performance.
- Entropy generation analysis provides insights into system irreversibility.
Purpose of the Study:
- To investigate heat transfer, fluid flow, and entropy generation within a Lada Niva catalytic converter.
- To validate simulation results with experimental pressure drop data.
- To identify flow characteristics and dominant entropy production regions.
Main Methods:
- Large Eddy Simulation (LES) for coupled heat and fluid flow analysis.
- Experimental measurement of pressure drop under various conditions.
- Darcy-Forchheimer relation for pressure drop extrapolation.
- Analysis of temperature-dependent thermophysical properties.
Main Results:
- LES predictions for pressure drop showed good agreement with experimental and extrapolated data.
- Identified flow features include impinging flow, stagnation, recirculation, flow separation, and laminarization.
- Entropy production is dominated by viscous dissipation in the monolith and by heat transport in the pipe regions.
Conclusions:
- The study successfully simulated complex phenomena within the catalytic converter.
- Flow behavior and entropy generation are significantly influenced by heat transfer and temperature-dependent properties.
- Insights gained can inform the design of more efficient catalytic converters.
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