Testing and characterisation of solar thermal absorbers

People

Supervisory Chair

Supervisor

Description

Solar energy is a vast and largely untapped resource in Australia, which has the highest solar radiation per square metre of any continent. Recently, central tower Concentrating Solar Power (CSP) technology has received significant attention due to its ability to cheaply store energy and produce electricity in a 24-hour cycle. Vital to the efficiency of central tower CSP technology is the effectiveness of light absorption at the solar receiver.

The central aim of this project is to develop highly efficient, durable, and economical competitive absorber coatings to help transform the CSP industry, which has the potential of becoming an essential part of the renewable energy sector in Australia and worldwide. To achieve the main objective, a multi-scale engineering approach composed of optics modelling, materials science, and ageing testing will be performed. In this project, three main goals are set. The first goal is to model and understand the light trapping mechanism of a micro-textured coating to find the best morphology that optimises light absorption (position 1). The second goal is to improve the durability and light absorption of solar thermal absorbers by developing micro-texturing and multi-layer deposition techniques as well as introducing new materials (position 2). The third goal is to develop and validate accelerated ageing tests that reproduce the extreme conditions of high temperature, radiative fluxes, thermal stresses and fatigue of CSP receivers (position 3).

The objectives of this HDR project are: to develop and validate accelerated ageing tests that reproduce the extreme conditions of high temperature, radiative fluxes, thermal stresses, and fatigue that are representative of a CSP receiver; to characterise and model optical/structural degradation phenomena in candidate absorber coatings; and to develop improved durability/optical performance coating structures, working closely with the material development stream (position 2). Initially, the tests will be conducted with Pyromark 2500, which is a state-of-the-art coating widely used in CSP. Then, the tests will be expanded to newly developed coatings within the group and by industry partner, NFT. Accelerated ageing tests under various conditions will be undertaken, e.g. non-isothermal under high-flux conditions. The characterisation of optical, mechanical and thermal properties of the aged coatings is also a key component of this research. The candidate will use the facilities at the Centre for Advance Microscopy (CAM) for material characterisation, the high-flux solar simulator in the Solar Thermal Group for ageing at high-fluxes, and the Thermal Optics Laboratory for measurement of heat transport properties of the coating. Changes to optical performance under aging will be understood by optical modelling, e.g. with Monte Carlo ray tracing approaches, working closely with the optics modelling stream (position 1). Degradation due to thermal stresses will be modelled by finite element approaches, and if significant, inform the development of layering and deposition processes for the absorber coating.

Requirements

  • Experience with thermal engineering design for experimental design and analysis
  • Ability to characterise material using various microscopy techniques.
  • Knowledge of geometrical optics and experience with Monte Carlo ray tracing tools.
  • Knowledge of numerical methods, preferably finite element methods.
  • Excellent scientific writing skills.

Keywords

concentrating solar power, solar thermal, absorber coating, optical modellling, light trapping, micro-textured coating, durability,

Updated:  1 November 2018/Responsible Officer:  Dean, CECS/Page Contact:  CECS Marketing