Effectiveness of horizontal air flow fans supporting natural ventilation in a Mediterranean multi-span greenhouse

López, Alejandro López; Valera, D.L.; Molina-Aiz, F.D.; Peña, Araceli

doi:10.1590/s0103-90162013000400001

Cited by 5 publications

(3 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The data also reveals that the drying time on each different kind of garments varies and are increasing. [12] Exposed that using fans inside the greenhouse helps the air to circulate and mix, giving rise to a more homogeneous inside temperature that increased the average value of normalized air velocity by 365 % and increased the average values of kinetic turbulence energy inside the greenhouse by 550 % compared to conditions of natural ventilation. The open and semi-open heat pump dryers could be greatly affected by ambient temperature and humidity while the closed heat pump drying system could be greatly affected by the bypass air rate [13].…”

Section: Observed Moisture Content For S-2mentioning

confidence: 99%

Drying of washed clothing utilizing solar powered dryer

Romero

N.V

2021

Bull. Sci. Res.

View full text Add to dashboard Cite

This study made setups that can be used in solar powered drying of washed clothing. This was used to analyze and test the performance, and determined if there is significant difference on the drying rate of set ups related to traditional and experimental method. A solar drying chamber was designed to use local materials in which the frame is made of bamboo with walls made of plastic to trap the heat of the sunlight entering the chamber. There were four set ups that were established in the gathering of data: S-1 is with electric fan, S-2 is with electric fan and electric flat iron, S-3 which did not use the drying chamber, is a traditional method where the garments C-1, C-2, C-3, C-4 & C-5 of different sizes, shapes, width and weight were dried under the heat of the sun. S-4 is almost similar to S-3 but the difference is that the garments were dried with no sunlight. The drying chamber alone is effective to reduce the moisture content of the garments using sunlight. Using the electric fan and electric flat iron increased the circulation of the enclosed hot air and boasted the drying capacity. Although it was computed that P > ? in comparison of the data in all set ups, it is insufficient to conclude that there is no significant difference on data of the experimental and traditional set ups since the data for the traditional set ups are not complete until the garments are totally dried.

show abstract

Section: Observed Moisture Content For S-2mentioning

confidence: 99%

Drying of washed clothing utilizing solar powered dryer

Romero

N.V

2021

Bull. Sci. Res.

View full text Add to dashboard Cite

show abstract

“…By adding the roof vent openings to the exhaust fans (MV2-NV), there was an increase in the difference in air temperature. The associated use of mechanical ventilation would not always imply less variation between the indoor and outdoor environments (López et al, 2013). The authors showed in a Mediterranean greenhouse that with fans placed at 4 m from the side vents, the entrance of outside air was insufficient to reduce the inside temperature on hot days with little wind.…”

Section: Differences Between Indoor and Outdoor Environmentsmentioning

confidence: 99%

“…Several studies evaluated the horizontal distribution in environments with mechanical ventilation systems (Balendonck et al, 2014), natural ventilation (Ferentinos et al, 2017;García-Ruiz et al, 2018) and natural ventilation associated with mechanical ventilation (Kittas et al, 2012;López et al, 2013). As to the vertical distribution, other studies also evaluated greenhouse microclimates with different systems, such as natural ventilation (Suay et al, 2008), or mechanical ventilation and evaporative cooling (Kutta and Hubbart, 2014;Zorzeto and Leal, 2017).…”

Section: Introductionmentioning

confidence: 99%

Wireless sensor network to identify the reduction of meteorological gradients in greenhouse in subtropical conditions

Cesar

Leal

Branquinho

et al. 2020

J Agricult Engineer

View full text Add to dashboard Cite

Spatial and temporal monitoring of temperature and relative humidity is essential for greenhouse management, therefore, wireless sensor networks (WSN) can offer crucial advantages. The objective of this work was to use a WSN to characterize and map the horizontal and vertical variability of air temperature and relative humidity inside a greenhouse using five different configurations. The configurations were based on combinations between the following actuating mechanisms: i) mechanical ventilation (by two exhaust fans); ii) natural ventilation (through the roof vent openings); iii) shading through the use of thermo-reflective screen. The WSN was designed with 45 spatially distributed measuring points, and the air temperature and relative humidity were recorded automatically every 30 seconds, for ten consecutive days, for each configuration. Our results show that the horizontal and vertical homogeneity of the meteorological elements depends on the actuating mechanism used in the greenhouse. Mechanical ventilation approximated the temperature and relative humidity of the indoor and outdoor air, with a homogeneous horizontal distribution throughout the environment. Opening the roof vent reduced vertical gradients of temperature and relative humidity. Our observations also showed that the combination of the use of roof vent openings with mechanical ventilation is an effective way to achieve horizontal homogeneity of meteorological elements.

show abstract