A mechanically reconfigurable metasurface that can continuously tune the wavefront is demonstrated in the visible frequency range by changing the lattice constant of a complex Au nanorod array ...fabricated on a stretchable polydimethylsiloxane substrate. It is shown that the anomalous refraction angle of visible light at 632.8 nm interacting with the tunable metasurface can be adjusted from 11.4° to 14.9° by stretching the substrate by ∼30%. An ultrathin flat 1.7× zoom lens whose focal length can continuously be changed from 150 to 250 μm is realized, which also demonstrates the potential of utilizing metasurfaces for reconfigurable flat optics.
The name of an author in the article by Weng et al. (2023) J. Synchrotron Rad.30, 546–554 is corrected.
Corrigendum to the article by Weng et al. (2023) J. Synchrotron Rad.30, 546–554.
•The solar air heater integrated with PCM was experimentally investigated.•Comparisons between the parameters affecting with and without PCM were presented.•The efficiency using PCM is 12% higher ...than the corresponding ones without PCM.
The purpose of this research is to carry out an experimental investigation of flat and v-corrugated plate solar air heaters with built-in PCM as thermal energy storage material. The integrated solar air heater with paraffin wax as PCM was designed and tested under prevailing weather conditions of Tanta city (30° 43′N, 31°E), Egypt. The parameters affecting the thermal performance of the flat and v-corrugated plate solar air heater were presented with and without PCM. These parameters include solar radiation, the temperature difference of air across the heater, convective heat transfer coefficient between the absorber plate and the flowing air, instantaneous thermal efficiency, daily average efficiency and the PCM freezing time.
The thermal performance parameters were studied when the mass flow rates were 0.062, 0.028 and 0.009kg/s. The effect of changing the thickness of PCM below the absorber plate was also studied. From the experimental results, it was found that when using the PCM, the outlet temperature of the v-corrugated plate solar air heater was higher than ambient temperature by 1.5–7.2°C during 3.5h after sunset compared with 1–5.5°C during 2.5h after sunset for flat plate solar air heater when the mass flow rate was 0.062kg/s. It was also concluded that the daily efficiency of the v-corrugated solar heater using PCM was 12% higher than the corresponding ones without using the PCM and it was also 15% and 21.3% higher than the corresponding values when the flat plate was used with and without PCM when the mass flow rate was 0.062kg/s, respectively.
