MATHEMATICAL MODELLING AND EXPERIMENTAL INVESTIGATION OF MULTI-PASS SOLAR AIR HEATING COLLECTOR SYSTEM ASSISTED BY POROUS MATRIX

United Nations target of renewable energy demands improvement on the solar
collector performance especially the solar air heating collector (SAHC) that has the
least contribution to solar energy utilisation. Traditional open sun air (direct) drying is
still popular with its shortcomings such as labour intensive and long drying time.
Thrust of this research work has been to model and test the performance of a new
multi-pass solar air heating collector (MPSAHC) system that stores sensible thermal
energy in the porous matrix. The MPSAHC system heat energy balance has been
analysed using finite difference approximation method while the gravimetric technique
has been used to study the mass transfer of moisture from screw-pine (Pandanus
tectorius) during drying operation under local weather condition of Seri Iskandar,
Perak Malaysia. Laboratory experiments on the characterisation of porous matrices
and oven drying operation using test chamber have been conducted. A series of
outdoor tests have been planned and conducted for a period of 12 months. System
temperature has been measured by sensors with uncertainty of �0:02, while other
equipment used were calibrated with at least 95% level of confidence. A measure of
relevant efficiencies has been determined from the data obtained during testing of the
prototype. Integrated MPSAHC without traditional back insulation has achieved
collector, exergy, pickup and drying efficiencies of 65%, 62