Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
NUMERICAL SIMULATION AND OPTIMIZATION OF THE GEOMETRIC PARAMETERS OF A HELICAL TAPE FOR THE INTENSIFICATION OF HEAT TRANSFER IN SOLAR COLLECTOR
Submission Author:
Daniel Museti , SP
Co-Authors:
Daniel Museti, Leandro Salviano
Presenter: Daniel Museti
doi://10.26678/ABCM.COBEM2019.COB2019-0874
Abstract
Nowadays, the thermal energy required for heating water in domestic or industrial application has significantly increased. Therefore, the solar energy has emerged as a suitable renewable energy source for this application, requiring permanent technology development on solar collector regarding its thermal efficiency in order to meet several application requirements. Overall, the main goal of the present research is to provide a numerical simulation and optimization procedure of the heat transfer enhancement through passive device known as Helical Tape, at low Reynolds number (Re = 300 and Re = 600) for a solar water heater with an active system and indirect single-phase flow. Helical Tape geometric parameters submitted to optimization procedure are: Position (translation) of the helical tape relative to the tube inlet, Pitch (P), Length (L) and Radius (R1 and R2). These five input variables were submitted to approach by Direct Optimization which is the integration between numerical model and optimization method (Genetic Algorithm). The results allow concluding that the application of helical tapes to enhance the heat transfer in a solar water heater is a very effective passive technique. The results of the pitch length optimization were 34 mm for Reynolds 600 and 33 mm for Reynolds 300. The intensification of the heat transfer obtained was 200% and 235% for Reynolds 300 and 600, respectively, when analyzing the pitch length optimization. And an asymmetric helical tape produced a significant increase in the heat transfer with moderate pressure drop penalty when compared to the conventional symmetrical helical tape with twist ratio of 4.
Keywords
Solar Energy, Solar Collector, Numerical simulation, Heat transfer, Helical Tape
