Parabolic trough collectors consist of parabolically shaped mirror surfaces in which the solar radiation is collected and concentrated in an absorber. A heat transfer fluid flows in the absorber tube and transports the heat to its destination.
With ET 203 the main aspects of solar thermal energy use with a parabolic trough collector can be investigated. For this purpose, solar radiation is focused by a parabolic mirror on an absorber tube. The radiation energy is absorbed and converted into heat. To reduce heat loss, the absorber tube is equipped with a double-walled glass envelope. Through a pipeline in the absorber, the heat is transferred to a heat transfer fluid in the solar circuit. Via a plate heat exchanger the heat is transferred to the hot water circuit and the storage tank. The parabolic trough collector can be tracked via two geared motors to track the position of the sun. Both control according to calculated astronomical data and sensor-based control are possible. The solar circuit is protected by an expansion tank and a safety valve. The temperatures in the storage tank, at the outlet and inlet of the collector and the flow in the solar circuit are measured.
Operation and control are carried out via the integrated PLC and touch screen. By means of an integrated router, the trainer can alternatively be operated and controlled via an end device. The user interface can also be displayed on additional end devices (screen mirroring). Via the PLC, the measured values can be stored internally. Access to stored measured values is possible from end devices via WLAN with integrated router/ LAN connection to the customer’s own network.
The parabolic trough collector can be pivoted and aligned vertically for experiments with the artificial light source HL 313.01. Rollers and movable supports make it possible to position and operate the test stand at a suitable outdoor location with little effort.