Performance analysis of solar chimney using mathematical and experimental approaches

Abstract

A mathematical model based on one-dimensional energy and mass balance across the solar chimney has been developed. The air flow characteristics such as exit velocity and temperature are evaluated with respect to the collector inclination angle, hourly solar radiation, ambient temperature, and wind speed. The model is validated by comparing the performance parameters obtained, with the experimental results and also with the experimental data of different geometrical range and environmental conditions from the literature. An average deviation of 8% for exit air velocity and 1.35% for exit air temperature is obtained for the solar chimney with absorber inclination angle 30°, collector area 0.41 m 2 , and chimney height 0.24 m. The experimental daily average and maximum exit air velocity during the month of April are 0.5 and 0.88 m/ s, respectively. The predicted optimum operating conditions are 75°inclination angle, 0.63 m 2 absorber area, and 0.48-m chimney height. The maximum average exit air velocity and temperature numerically obtained are 0.64 m/s and 331 K, respectively, when operating with optimum conditions. It is observed that the exit air velocity increases 33% by increasing the absorber area from 0.5 to 3 m 2 for a solar chimney with 0.5 m height. An increase in exit air velocity of 52% was obtained by increasing the chimney height from 0.5 to 3 m for a solar chimney with 0.64 m 2 absorber area. A reduction in exit air velocity of 4% was observed for the increment in wind flow over the glass cover from 1.5 to 3 m/s. These results confirm that the solar chimney could be designed based on the predicted monthly performance by the present model.

Performance characteristics of divergent chimney solar updraft tower plant

“…They proposed a system for smooth power output and continuous operation of the plant. Sivaram et al 7 performed both numerical and experimental analysis on SUT to evaluate the effect of geometrical parameters such as collector inclination angle (θ cc ), absorber plate area and H ch on the performance of the system. It was observed that there was an enhancement of 52% exit air velocity due to increase in H ch from 0.5 to 3 m. Cao et al 8 numerically analysed the effect of solar intensity, air velocity and ambient temperature (T a ) on the performance of the system.…”

“…It was found that there are lots of experimental and numerical works 3,4,7,8,10,13,17,20,22,25 on estimating the flow parameters such as velocity, pressure and temperature distributions of SUT plant. Some more attempts have been made in this direction using advanced models like ANN and genetic algorithm to predict the performance of the system.…”

“…Very few studies 14,[17][18][19]21 have been found on CC/DC-SUT plant. Most of the studies were related to chimney configurations and based either on theoretical analysis 7,11,18 or 2D numerical analysis. 14,17,19 It has been established that chimney is one of the most influential components and highly sensitive to the flow phenomena and performance properties.…”