Mono- and Multi-Objective CFD Optimization of Graded Foam-Filled Channels

Area of Science:

• Heat Transfer Engineering
• Materials Science
• Computational Fluid Dynamics

Background:

• Graded foam-filled channels offer significant potential for enhancing heat sink thermal performance due to their customizable structures.
• Optimizing these structures is crucial for maximizing heat transfer efficiency while managing pressure drop.

Purpose of the Study:

• To develop a comprehensive optimization framework for the design of graded foam-filled channels under uniform heat flux.
• To investigate both mono- and multi-objective optimization strategies for thermal performance and fluid-dynamic characteristics.

Main Methods:

• Parameterization of spatial distributions for porosity and Pores Per Inch (PPI) to achieve graded foam structures.
• Implementation of mono-objective optimization targeting the Performance Evaluation Criterion (PEC) and multi-objective Pareto optimization for trade-offs.
• Assumption of local thermal non-equilibrium conditions within the foam during optimization.

Main Results:

• A maximum PEC value of 1.51 was achieved with specific design variables (e.g., porosity gradients, PPI distributions).
• Multi-objective optimization identified optimal trade-off solutions, including high heat transfer coefficients (e.g., 502 W/m²K) and low pressure drops (e.g., 80 Pa).
• Specific optimal values for key design parameters and performance metrics were determined.

Conclusions:

• The proposed optimization framework effectively designs graded foam-filled channels for superior thermal performance.
• Optimal solutions offer valuable insights for the thermal design of heat sinks, balancing heat transfer enhancement and pressure drop.
• The study provides practical guidelines for engineers designing advanced thermal management systems using graded foams.