Experimental and analytical study of the heat transfer characteristics of a solar air heater incorporating a finned absorber

Thesis/Dissertation · Thu Jan 01 00:00:00 EST 1981

OSTI ID:5464177

Diab, M R

A realistic analysis is made of a general class of flat-plate solar air heaters in order to determine the significant design or operating parameters which effect collector thermal performance. The results of this analysis are used to study the parametric effect of the airflow passage arrangement, number of cover plates, cover-to-absorber plate spacing, absorber-to-back plate spacing, airflow rate, inlet-to-ambient temperature difference, insulation thickness, and wind speed. The results of this analysis indicate that collector efficiency is significantly improved by increasing the effective absorber-to-air heat transfer coefficient three to four times the value pertinent to the simple flat-plate collector at the same operating conditions. The results also indicate that collector performance is insensitive to any additional increase in the heat transfer coefficient. Based on the above finding, a continuous fin configuration has proven to be a potential improvement in collector design. Several experiments were undertaken to study the heat transfer characteristics of this type of collector design to provide more insight into the heat transfer process. An algorithm was developed to reduce the finned test absorber experimental data to yield heat transfer coefficients. Graphical heat transfer correlations are presented which can be used in the thermal analysis of finned collectors. A rigorous numerical analysis was developed in order to give the experimental results a theoretical basis. The analytical procedure is based on the simultaneous solution of the conservation equations to yield velocity, pressure, and temperature distributions from which flow characteristics are determined. Results of the numerical analysis are compared with the present experimental results and with available theoretical predictions.

• OSTI ID: 5464177
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
FLAT PLATE COLLECTORS
HEAT TRANSFER
THERMAL ANALYSIS
SOLAR AIR HEATERS
AIR FLOW
ALGORITHMS
COVERINGS
DESIGN
EFFICIENCY
FINS
FLUID FLOW
PERFORMANCE TESTING
PRESSURE DEPENDENCE
SENSITIVITY
SOLAR ABSORBERS
TEMPERATURE DISTRIBUTION
TEMPERATURE EFFECTS
VELOCITY
AIR HEATERS
ENERGY TRANSFER
EQUIPMENT
GAS FLOW
HEATERS
MATHEMATICAL LOGIC
SOLAR COLLECTORS
SOLAR EQUIPMENT
TESTING
141000* - Solar Collectors & Concentrators