An experimental and analytical study on the feasibility of SMA spring driven actuation of an iris mechanism Academic Article uri icon


  • 2016 Elsevier Ltd Variation in incoming solar energy adversely affects the temperature inside a solar reactor and lowers its efficiency. Therefore, it is important to develop a mechanism that can maintain semi-constant temperatures inside the reactor from sunrise to sunset. In this paper, we present an iris mechanism that reduces or enlarges its circular opening with the use of NickelTitanium Shape Memory Alloy (SMA) springs. SMA springs possess memory of their shapes at certain temperatures. Hence, by controlling the temperature of the spring, it is possible to exert different forces that may then be transferred to the variable aperture mechanism. In this study, variation of the force exerted by an SMA spring with respect to temperature was experimentally tested and the viability of an SMA spring's use in actuating an iris mechanism aperture was examined. In order to simulate conditions under fluctuating solar radiation, a 7kW solar simulator was used in experiments at varying power levels. It was observed that SMA springs are promising as a replacement of the actuation mechanism driven by a motor.

published proceedings

  • Applied Thermal Engineering

author list (cited authors)

  • Rajan, A., Abouseada, M., Manghaipathy, P., Ozalp, N., Majid, F. A., Salem, A., & Srinivasa, A.

citation count

  • 6

complete list of authors

  • Rajan, Aravindh||Abouseada, Mostafa||Manghaipathy, Pavithra||Ozalp, Nesrin||Majid, Feras Abdul||Salem, Ayman||Srinivasa, Arun

publication date

  • July 2016