Solar Energy, Vol.93, 280-293, 2013
A transient model for the heat exchange in a solar thermal once through cavity receiver
This paper presents a dynamic model of a once-through-to-superheat solar steam receiver for electricity generation. The receiver is a mono-tube cavity boiler mounted at the focal point of a 500 m(2) paraboloidal dish concentrator at the Australian National University. The dynamic model is derived from physical principles of mass and energy conservation, and uses a moving boundary formulation, coupled with a switching approach, to represent outlet flow, ranging from sub-cooled liquid to superheated steam. A method to compute outlet mass flow rate for all three receiver outlet flow conditions is included. This modelling approach results in a compact state-space representation of the receiver which is useful in the development of model-based control strategies for the operation of the receiver in a concentrator plant. The model is implemented in TRNSYS 16 and validated with experimental data from the Australian National University 500 m(2) dish system. (C) 2013 Elsevier Ltd. All rights reserved.
Keywords:Direct steam generation;Transient two-phase flow modelling;Concentrating solar thermal power;Moving boundary formulation