NUMERICAL STUDY ABOUT THE INFLUENCE OF GEOMETRIC PARAMETERS ON THE AVALIABLE POWER IN A SOLAR CHIMNEY BY MEANS OF CONSTRUCTAL DESIGN
Rodrigo Spotorno Vieira1; Christopher Garcia1; Jeferson Avila Souza1; Luiz Alberto Oliveira Rocha2; Liércio André Isoldi1; Elizaldo Domingues dos Santos1
1 Universidade Federal do Rio Grande (FURG); 2 Universidade Federal do Rio Grande do Sul (UFRGS)
doi:10.20906/CPS/COB-2015-2311
Resumo
In the presented work, it is made a numerical study about the main physical principle of a solar chimney (SCPP - Solar Chimney Power Plant) and the influence of some geometric parameters on the available power in the SCPP. The geometrical evaluation is performed according to Constructal Design. The problem has three constraints: the collector region (A1), turbine region (A2) and chimney region (A3) areas, which are defined according to previous studies of literature. Moreover, the problem geometry is submitted to three degrees of freedom: R/H (ratio between the collector radius and collector inlet height), R1/H2 (ratio between the chimney outlet radius and chimney height) and H1/H (ratio between the collector and internal collector heights). The main purpose here is to obtain a theoretical recommendation about the influence of geometric ratios over the available power of the SCPP. In the present study it is investigated the effect of the ratio R/H for two different ratios of R1/H2. The ratio H1/H is maintained fixed (H1/H = 6.25). In the present work, the fluid flow is considered incompressible, turbulent at the steady state and with mixed convective heat transfer. The device domain is considered axisymmetric domain. The conservation equations of mass, momentum and energy are numerically solved using the finite volume method, more specifically with the FLUENTTM software. To tackle with turbulent flow the standard k - ε model is applied into the RANS framework. For the studied cases, Constructal Design allowed the improvement of available power. The best performance was almost 46% higher than the worst evaluated geometry. It was also seen that the ratio R/H has a large sensibility in the available power.
Palavras-chave: Constructal Design; Solar chimney; Geometric optimization; Numerical study