Radiative transport in transparent aerogels for solar thermal energy applications

Solar-thermal energy conversion systems hold great promise to meet our diverse energy demand by a renewable source. Converting sunlight into thermal energy requires solar radiation to be absorbed and transformed into heat effectively while minimizing system thermal loss to the ambient environment. Traditional solar-thermal systems utilize high optical concentration and vacuum enclosure to reduce the impact of heat loss. However, the cost of sophisticated optical and thermal components limits their market adoption to date. In this thesis, we explored the development of transparent aerogels for enhancing solar-thermal energy conversion. We established and validated a modeling framework to understand the fundamental light transport within an aerogel sample and yield helpful guidance for material development. We performed synthesis recipe optimization through a systematic parametric study and discovered a facile procedure to fabricate low-scattering aerogel samples with >95% solar transmittance. We then incorporated the developed aerogel in solar-thermal collectors and tested the performance. Under unconcentrated sunlight, stagnation temperature beyond 265 °C can be reached and saturated steam above 120 °C can be generated without vacuum enclosures or selective surfaces. The improvements enabled by the low-scattering aerogels promote a new pathway of solar energy utilization for domestic, industrial, and power generation applications..

Name thesis:degree_name

Doctoral

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Mechanical Engineering

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2019

Author dc:creator

• Zhao, Lin,Ph. D.Massachusetts Institute of Technology.

Advisor dc:contributor.advisor

• Evelyn N. Wang.

• Mechanical Engineering.

Statement dc:rights

• MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/123778

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/123778