High-Temperature Linear Radiation-Cavity Solar Collector with a Fresnel Concentrator.
Abstract
A model solar-thermal concentrator-collector that is 1/6th scale (in cross section) relative to a system considered to be of practical dimensions for power generation has been constructed and tested. It consists of an Archimedes (i.e., Fresnel) mirror-concentrator, 5 cm ID x 1.5 m long glass receiver pipe, 0.3 cm thick graphite absorber, and gaseous (Ar) heat transfer medium. On clear days (direct solar flux ca. 800 W/sq.m.), stagnation (i.e., no-flow condition) temperatures of ca. 370 C have been reached at the center of the experimental device, where end effects are minimal. Experiments have been performed with gas flow rates up to ca. 100 liters/min (200 RE 2000), resulting in a bulk fluid temperature rise in the axial (flow) direction of up to 285 C. These experiments have been utilized in a study of heat transfer processes within the collector. A computer model of this system which takes into account most of the influential variables (e.g., combined forced-free convection, establishment of velocity and temperature profiles, and axial heat conduction) has been developed. Its behavior agrees well with observations. Also, after ca. 200 h of high-temperature operation, materials degradation was measured and found to be very low.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 08, 1977
- Accession Number
- ADA049982
Entities
People
- Zenen I. Antoniak
Organizations
- Pennsylvania State University