TY - JOUR
TI - Three dimensional CFD analysis of buoyancy-driven natural ventilation and entropy generation in a prismatic greenhouse
AU - Aich Walid
AU - Kolsi Lioua
AU - Borjini Mohamed Naceur
AU - Al-Rashed Abdullah A. A. A.
AU - Aissia Habib Ben
AU - Öztop Hakan F
AU - Abu-Hamdeh Nidal
JN - Thermal Science
PY - 2018
VL - 22
IS - 1
SP - 73
EP - 85
PT - Article
AB - A computational analysis of the natural ventilation process and entropy  generation in three-dimensional (3-D) prismatic greenhouse was performed  using computational fluid dynamics (CFD). The aim of the study is to  investigate how buoyancy forces influence airflow and temperature patterns  inside the greenhouse having lower level opening in its right heated facade  and also upper level opening near the roof top in the opposite cooled facade.  The bottom and all other walls are assumed to be perfect thermal insulators.  Rayleigh number is the main parameter which changes from 103 to 106 and  Prandtl number is fixed at Pr =0.71. Results are reported in terms of  particles trajectories, iso-surfaces of temperature, mean Nusselt number, and  entropy generation. It has been found that the flow structure is sensitive to  the value of Rayleigh number and that heat transfer increases with increasing  this parameter. Also, it have been noticed that, using asymmetric opening  positions improve the natural ventilation and facilitate the occurrence of  buoyancy induced upward cross-airflow (low-level supply and upper-level  extraction) inside the greenhouse.