Enhanced Solar Collection Efficiency Using Microscale Physics

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Microscale features are smaller than a human hair is thick, but if designed properly they can increase the amount of sun's energy that can be collected and used. Given how much energy we use in the US and our diminishing fuel supply, this could be pretty important. In our lab, we add microscale channels to conventionally smooth surfaces and determine how much more of the sun's energy is being absorbed by that surface. Typically, the microstructured surfaces collect 40% more of the sun's energy.

Keywords

Related Topics

  • Solar Thermal Propulsion
  • Microchannels
  • Concentrated Solar Power

Project Timeline

  • Project Began: June 1, 2010
  • Project Ended: June 1, 2011

 

Principal Investigators:

 

Picture of the test pieces from Dr. Webb's research

Microstructured test pieces A, B, C, D,
and E from left to right

Results and Impacts

Solar thermal propulsion (STP) is a viable alternative to conventional chemical rocket propulsion. Microsatellite systems utilizing STP can achieve comparable thrust and specific impulse as chemical counterparts. A system that uses ammonia propellant and has pre-nozzle temperatures exceeding 2500 K can achieve specific impulse values 407s [1]. A key component of the STP system is the solar collection subsystem. The objective of this work was to use microscale physics to improve the efficiency of this collection system and as a result increase propellant temperature.

For you visual learners, this is a picture of the test results...
Click to enlarge
Energy absorbed (ΔT) by each microstructured test piece and compared to a smooth control piece at varying angles of incidence.

Publications

Horvath, J.A., Webb, R.N., 2011, “Experimental Study of Radiation Absorption by Microchannels of Varying Aspect Ratios,” 85, pp. 1035 – 1040.

Webb, R., Horvath, J., and Boartfield, A., "Enhanced Heat Collection Element Performance Through Surface Geometry," in 5th International Conference on Energy Sustainability, Washington, DC, Pending Publication.

 

Links

SECanT Laboratory Homepage: http://www.eas.uccs.edu/rwebb/

Check-out the SECanT Website

More Pictures

These are the SECanT Researchers

SECanT Laboratory research group

 

Page last edited by JI on 7-20-11