Abstract: | Innovative tracking heat flux sensors located at or near the solar
collector's focus for centering the concentrated image on a receiver
assembly. With flux sensors mounted near a receiver's aperture, the flux
gradient near the focus of a dish or trough collector can be used to
precisely position the focused solar flux on the receiver. The heat flux
sensors comprise two closely-coupled thermocouple junctions with opposing
electrical polarity that are separated by a thermal resistor. This
arrangement creates an electrical signal proportional to heat flux
intensity, and largely independent of temperature. The sensors are
thermally grounded to allow a temperature difference to develop across
the thermal resistor, and are cooled by a heat sink to maintain an
acceptable operating temperature. |