3-Dimensional Thermal Analysis of a Screenhouse With Plane and Multispan Roof by Using Computational Fluid Dynamics (Cfd)

Microclimatic behavior of a screen house proposed for horticultural production in low-altitude tropical climate conditions

“…The normalized speed, which represents the ratio of the indoor airflow speed to the outdoor airflow speed, showed a significant reduction in the air movement speed inside the SH with values up to 68% lower than the outdoor wind speed value (Table 3) as a function of the porosity of the screen used (Teitel et al, 2020). The values found for this study are within the range reported in a previous study by Flores-Velazquez et al (2013) and are slightly higher than those calculated for Teitel et al (2018).…”

“…Once the fit of the CFD model was verified, it was used to determine the thermal behavior and airflow patterns within the SH, each simulation included specific initial conditions recorded in the SH external environment for the hours of the day between 6:00 and 18:00 (Table 2). where a large part of the airflow leaves the structure through the roof area; therefore we can conclude that the difference in flow pattern may be influenced by the shape of the SH roof evaluated in this study, which due to its shape causes pressure gradients that allow airflow into the SH (Flores-Velazquez et al, 2013). On the other hand, another common feature in the airflow patterns for this structure is a convective cell that forms over the central zone of the SH (z-axis), where the airflow vectors move from the floor area to the roof of the structure ( Figure 5).…”

“…The simulated thermal distribution in the x and z axes, as well as in a plan view at a height of 1.5 m above ground level, allowed us to observe that inside the SH there is a heterogeneous temperature behavior, where the cooler regions are located on the windward side and the warmer regions are located on the central and leeward side of the SH (Figure 6). This thermal distribution behavior is related to the air flow fields, therefore, higher speed regions are the cooler temperature regions and on the contrary the warm regions are presented in the areas of lower flow velocity, this is characteristic of the ventilation phenomenon in screen houses (Al-Mulla et al, 2008;Flores-Velazquez et al, 2013) and greenhouses (Villagrán & Bojacá, 2019a). Villagran & Jaramillo (2020) Microclimatic behavior of a screen house...…”

“…The study of the microclimatic behavior of SH is not as generalized as that of conventional greenhouses, but probably has contributed empirically to the implementation of SH despite the lack of research on aspects such as architecture, the geometry of the structure and the type of mesh used (Flores-Velazquez et al, 2017). The existing studies on the microclimate in the SH have been addressed mainly through experimental approaches and through numerical computational fluid simulation (CFD) as can be reviewed in Mahmood et al (2018), and in studies analyzing thermal and aerodynamic behavior (Tanny et al, 2008;Teitel et al, 2014Teitel et al, , 2017, as well as the effect of the screen pore size (Kalcsits et al, 2017;Tanny et al, 2018), and the shape and geometry of the structure (Flores-Velazquez et al, 2013).…”

Two-Dimensional Numerical Study of the Microclimate Generated in Three Screenhouses for the Climatic Conditions of the Colombian Caribbean

“…Therefore, it is recommended that before the construction of an S-HM a design phase should be carried out. One of the design tools that has the capacity to generate an approximation to the probable microclimatic conditions that would be generated within an S-MH, is the computational fluid dynamics (CFD), a technique that has been widely used in greenhouses [17,18] and in some screenhouses studies [19][20][21].…”