The effects of collector roughness shape on the performance of solar chimney power plant were investigated in this study. The roughness shapes of triangular, curved, and square grooves were chosen and were compared to smooth case. The performance parameters of solar radiation, updraft velocity, temperature distribution, static pressure, power, and Nusselt number were varied. The effects of number, position, height, and width of the grooves on the performance were investigated. The results of this investigation show that the updraft velocity with the triangular groove increases by 1.5 times compared to the smooth case at solar radiation of 1000 W/m2. At solar radiation of 1000 W/m2, the power increases by 169%, 96%, and 19% for triangular, curved, and square grooves, respectively, compared to the smooth case. Moreover, the Nusselt number values with triangular groove and curved groove enhance by 42% and 26%, respectively, compared to the smooth case. The power increases by 1.98% for three grooves instead of using one groove at higher solar radiation. Increasing the groove height by 1.7 times, the power increases by 1.03 times at higher solar radiation. The power enhancement shows less sensitivity to the change of groove width at higher solar radiation.
