Thermal and acoustic response of mathematically-designed heat spreaders

Abstract

This thesis focuses on the design of funnel-shaped heat spreaders that act as point-to-plane heat source converters. The main objective is to render uniform distributions of heat through the spreader geometry. Transformation-based methods associated to metamaterial design are applied first to obtain three metamaterial heat spreaders: two with a trapezoidal geometry and one with a conical geometry. Realisable approximations of the obtained metamaterials are proposed using bi-layered laminates and a selection of natural materials. A second approach is then developed where the spreader is split into two or three components - each made of a natural material. The solution to the heat equation is exploited for these simple configurations, referred to as neutral layers. The thermal performance of each realisable heat spreader, which is dictated by the temperature variation of the large top surface or the average temperature of the base, is validated numerically. The thermal performance of an infinite periodic array of spreaders is also investigated. As engineering problems naturally involve multiple physics it is important not to consider the heat spreaders in isolation. The last chapter of this thesis therefore focuses on a series of acoustic scattering problems (where the spreader is the scatterer). The acoustic performance, which is dictated by the scattering cross-section for a single spreader and reflection and transmission coefficients for an array of spreaders, is numerically quantified. A trade-off between thermal and acoustic performance is then presented.

Date of Award	1 Aug 2023
Original language	English
Awarding Institution	The University of Manchester
Supervisor	William Parnell (Supervisor) & Raphael Assier (Supervisor)