Date of Award

6-2014

Document Type

Open Access

Degree Name

Bachelor of Science

Department

Physics and Astronomy

First Advisor

Samuel Amanuel

Language

English

Keywords

heat, capacity, changes, composites, energy

Abstract

One of the major difficulties in development of renewable energy is the lack of an adequate and economical means of energy storage. In the case of concentrated solar power a large mass of thermal fluid is required to store a reasonable amount of energy. This is primarily because the fluids tend to have a low specific heat capacity. Formulating composites of these fluids can enhance their specific heat capacity and avails opportunities to make concentrated solar power more attractive. In most cases, the specific heat capacity of composite materials is a weighted average of the individual component heat capacities. This, however, does not take into account interfacial effects where the heat capacity could be different. Although these changes in heat capacity may be small in traditional composites, they could be significant in the case of nano-composites, due to the larger surface area to volume ratios on the nano-scale level. From our phase transition studies of fluids confined in nano-pores, we have demonstrated that the molecules at the interface have different thermodynamic behavior than the bulk material. To study small changes in heat capacity values, we performed systematic studies on empty sample pans and developed a baseline useful in measuring small changes in heat capacity using a power compensated differential scanning calorimeter. Through our measurements we found that leaving the DSC refrigerator running for over twenty-four hours, and proper delicacy in placing the sample pans into the DSC improve the precision of heat flow values.

Share

COinS