Development of Methods for Optimal Control and Management of Solar Heat Supply Systems: A Numerical Analysis

Abstract

This is an example of a paper that will provide a numerical simulation study on analytical solutions for optimal control of solar heat supply systems (SHSS). It will develop and solve a mathematical model for the “solar collector - storage tank” subsystem using a finite element technique and standard k-epsilon turbulence closure, derive an optimal pump speed control law for maximizing heat delivery to the storage tank, through a collection of output heat functions demonstrated as quadratic with respect to flow rate G opt for each instantaneous solar insolation level J, continuously determine G opt through algorithm methodology based on microcontroller maximum heat exchange outlet temperature and non-volatile “J-G” maps in memory for rapid response to non-stationary irradiance conditions. The simulation results demonstrated that the proposed strategy can achieve a seasonal thermal efficiency increase of 11-22 percentage points compared to conventional ON/OFF differential temperature control while increasing the pressure drop only 10.3%. In addition, the thermal-enhancement of peak Nusselt number (18.9%) and Performance Evaluation Criterion (1.15) indicates that there is a net thermohydraulic benefit to implementing the proposed strategies. The results of the study quantitively identify tuning of controllers and sizing of heat exchangers in residential and commercial solar installations.