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Entropy Generation Analysis and Thermodynamic Optimization of Jet Impingement Cooling Using Large Eddy Simulation
Florian Ries1, Yongxiang Li1, Kaushal Nishad1
1Institute of Energy and Power Plant Technology, Technische Universität Darmstadt, 64287 Darmstadt, Germany.
Entropy (Basel, Switzerland)
|December 3, 2020
Summary
Entropy generation analysis optimizes turbulent impinging jets for efficient cooling. Normal jet impingement on heated surfaces minimizes energy loss, enhancing thermodynamic performance and thermal efficiency.
Area of Science:
- Thermodynamics
- Fluid Dynamics
- Heat Transfer
Background:
- Turbulent impinging jets are crucial for cooling applications.
- Understanding entropy generation is key to optimizing thermodynamic performance.
Purpose of the Study:
- To characterize and optimize turbulent impinging jets on heated surfaces using entropy generation analysis.
- To investigate the effects of plate inclination and Reynolds number on flow and heat transfer.
Main Methods:
- Numerical investigation using Large Eddy Simulation (LES).
- Derivation of novel model equations for entropy generation rates, including subgrid-scale effects.
- Post-processing analysis of local entropy generation.
Main Results:
- Plate inclination shifts stagnation points and maximal Nusselt numbers.
- The impinged wall is a primary source of irreversibility.
- Normal jet impingement offers the highest energy efficiency and lowest exergy loss.
Conclusions:
- Increasing Reynolds number enhances heat transfer and second-law efficiency.
- Thermal efficiency gains can outweigh frictional exergy losses.
- Optimal designs for jet impingement cooling are identified.
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