Performance Optimizations with Single-, Bi-, Tri-, and Quadru-Objective for Irreversible Diesel Cycle.

Area of Science:

• Thermodynamics
• Mechanical Engineering
• Computational Fluid Dynamics

Background:

• The Diesel cycle is a fundamental internal combustion engine cycle.
• Irreversibilities significantly impact engine performance and efficiency.
• Finite time thermodynamics provides a framework for analyzing and optimizing cycles with losses.

Purpose of the Study:

• To perform thermodynamic analysis and multi-objective optimization of an irreversible Diesel cycle.
• To investigate the influence of cycle parameters on power density and thermal efficiency.
• To determine optimal design strategies considering multiple performance criteria.

Main Methods:

• Application of finite time thermodynamics theory.
• Utilizing the non-dominated sorting genetic algorithm-II (NSGA-II) for multi-objective optimization.
• Employing LINMAP, TOPSIS, and Shannon entropy for solution comparison.

Main Results:

• Analysis of the impact of cycle temperature ratio on power density.
• Established relationships between power density, compression ratio, and thermal efficiency under various loss conditions.
• Identified optimal design schemes through single-, bi-, tri-, and quadru-objective optimizations.

Conclusions:

• Multi-objective optimization yields a small deviation index, indicating robust solutions.
• Tri-objective optimization of power output, ecological function, and power density using LINMAP provides the minimum deviation index (0.1333).
• The study offers a pathway to achieving near-ideal design schemes for irreversible Diesel cycles.