Optimal Design of Additively Manufactured Fin Topology for a Two-Phase Flow Channel Using Multi-Objective Genetic Algorithms

Open Access
- Author:
- Luu, Anthony
- Area of Honors:
- Mechanical Engineering
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Matthew J Rau, Thesis Supervisor
Anne Elizabeth Martin, Thesis Honors Advisor
Mary I Frecker, Thesis Supervisor - Keywords:
- fins
topology
optimization
heat transfer
genetic algorithm
two-phase flow
multi-objective optimization
additive manufacturing
mechanical engineering - Abstract:
- Through development of additive manufacturing, objects of certain materials are now able to be designed with increased complexity. As a result, applications in which traditional structures consisting of simple geometries can now be re-examined and optimized. This study examines a two-phase flow heat exchanger motivated by a potential of increased performance as well as lack of research present in the field. Specifically, this study examines the optimal design characteristics of an annularly finned heat exchanger in a uniformly cooled crossflow environment. To optimize the design of a heat exchanger for competing objectives, heat transfer and pressure drop, a multi-objective genetic algorithm is employed. This methodology was selected due to the low number of variables used, its likelihood to converge to the global optima, its ability to support multiple objectives, and its ease of implementation in MATLAB. A compact heat exchanger correlation was used to evaluate the pressure drop of the system, and a flat plate correlation was used in combination with a cylinder in cross flow correlation to evaluate the heat transfer of the system. This study is organized into 3 case studies that investigates the optimal designs of the heat exchanger with different aspects of design freedom. The results of these case studies have revealed that different variables have a larger impact than others when selecting the optimal design for a user’s specified performance. It is also found that increasing the design freedom considered does not have a significant impact on performance. Additionally, it was found that introducing a temperature profile does not have an effect on the placement of fin mass along a channel. Finally, it was observed that for various levels of constant pressure drop, the total heat transfer of the system was not affected by the mass flux of a surrounding fluid. Despite these findings, interest in introducing additional design variables for a more optimal performance and unrestricting experimental constraints for a wider range of results provides interest in future work.