Concentrating solar thermal (CST) power tower (PT) is one of the most promising renewable technologies for large-scale electricity production, however the main limitation of PT systems is their significantly larger levelised cost of electricity (LCOE) relative to base load energy systems. One opportunity to lower the LCOE is to reduce the capital cost of heliostats through optimisation of the size and position of heliostat mirrors to withstand maximum wind loads during high-wind conditions when aligned parallel to the ground in the stow position.Wind tunnel experiments were carried out to measure the forces on thin flat plates of various sizes at a range of heights in a simulated part-depth atmospheric boundary layer (ABL). Both the peak lift coefficient and peak hinge moment coefficient on the stowed heliostat were highly dependent on the turbulence in the ABL, such as the size of the largest eddies represented by the integral length scale. Surface pressure distributions indicated the presence of large-scale eddies at the leading edge of the heliostat mirror for consideration of critical failures due to large hinge moments about the elevation axis. Results showed that both lift forces and hinge moments on a stowed heliostat could be minimised by lowering the elevation axis height to less than half that of the mirror chord length and increasing the chord length of the heliostat mirror to no less than five times smaller than the longitudinal integral length scales in the ABL.
Matthew Emes, University of Adelaide, Australia
Farzin Ghanadi, University of Adelaide, Australia
Maziar Arjomandi, University of Adelaide, Australia
Richard Kelso, University of Adelaide, Australia
Stream: Energy: Renewable Energy and Environmental Solutions
This paper is part of the ECSEE2017 Conference Proceedings (View)
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