Climate Control in Mediterranean Greenhouses

This paper aims at explaining testing procedures used to evaluate the potential of natural ventilation and daylighting applications to passive design of housing in Ghana. The objectives of research were to reduce energy costs and increase the sustainability of housing. From the results of these experiments actual and potential designs are illustrated and discussed. Mass housing results in multi-storey buildings which require substantial artificial lighting and ventilation. Also, with the increasing usage of glass for windows and doors in Ghana, even the shaded depths of buildings require additional daylight usually resulting in more energy consumption. By supplementing the internal lighting levels with daylight, reducing the internal heat load by shading windows to direct radiation and the utilization of natural ventilation over air conditioning where possible, significant energy savings are could be achieved. The research proposes mass housing design changes such as: delivering daylight above the suspended ceiling into the depths of the building by horizontal light pipes and natural ventilation, utilizing stack effect and wind siphonage, etc.

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Active Control of Greenhouse Climate Enhances Papaya Growth and Yield at an Affordable Cost

Agronomy ◽

10.3390/agronomy11020378 ◽

2021 ◽

Vol 11 (2) ◽

pp. 378

Author(s):

Irene Salinas ◽

Juan José Hueso ◽

Julián Cuevas

Keyword(s):

Active Control ◽

Skin Color ◽

Natural Ventilation ◽

Control Strategies ◽

Soluble Solids ◽

Growth And Yield ◽

Climate Control ◽

Tropical Fruit ◽

Greenhouse Climate ◽

Solids Content

Papaya is a tropical fruit crop that in subtropical regions depends on protected cultivation to fulfill its climate requirements and remain productive. The aim of this work was to compare the profitability of different climate control strategies in greenhouses located in subtropical areas of southeast Spain. To do so, we compared papayas growing in a greenhouse equipped with active climate control (ACC), achieved by cooling and heating systems, versus plants growing in another greenhouse equipped with passive climate control (PCC), consisting of only natural ventilation through zenithal and lateral windows. The results showed that ACC favored papaya plant growth; flowering; fruit set; and, consequently, yields, producing more and heavier fruits at an affordable cost. Climate control strategies did not significantly improve fruit quality, specifically fruit skin color, acidity, and total soluble solids content. In conclusion, in the current context of prices, an active control of temperature and humidity inside the greenhouse could be a more profitable strategy in subtropical regions where open-air cultivation is not feasible.

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Climate control of cambial dynamics and tree-ring width in two tropical pines in Thailand

Agricultural and Forest Meteorology ◽

10.1016/j.agrformet.2021.108394 ◽

2021 ◽

Vol 303 ◽

pp. 108394

Author(s):

Nathsuda Pumijumnong ◽

Piyarat Songtrirat ◽

Supaporn Buajan ◽

Sineenart Preechamart ◽

Uthai Chareonwong ◽

...

Keyword(s):

Tree Ring ◽

Ring Width ◽

Tree Ring Width ◽

Climate Control

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Simultaneous PAN Carbonization and Ceramic Sintering for Fabricating Carbon Fiber-Ceramic Composite Heaters

Applied Sciences ◽

10.3390/app9224945 ◽

2019 ◽

Vol 9 (22) ◽

pp. 4945 ◽

Cited By ~ 1

Author(s):

Daiqi Li ◽

Bin Tang ◽

Xi Lu ◽

Quanxiang Li ◽

Wu Chen ◽

...

Keyword(s):

Carbon Fiber ◽

Thermal Performance ◽

Ceramic Composite ◽

Ceramic Composites ◽

Indoor Climate ◽

Climate Control ◽

Ceramic Tiles ◽

Ceramic Sintering ◽

Physical Features ◽

Pan Fibers

In this study, a single firing was used to convert stabilized polyacrylonitrile (PAN) fibers and ceramic forming materials (kaolin, feldspar, and quartz) into carbon fiber/ceramic composites. For the first time, PAN carbonization and ceramic sintering were achieved simultaneously in one thermal cycle and the microscopic morphologies and physical features of the obtained carbon fiber/ceramic composites were characterized in detail. The obtained carbon fiber/ceramic composite showed comparable flexural strength as commercial ceramic tiles. Meanwhile, the composite showed exceptional electro-thermal performance based on the electro-thermal performance of the carbonized PAN fibers, which could reach 108 ℃ after 15 s, 204 ℃ after 90 s, and 292 ℃ after 450 s at 5 V (2.6 A), thereby making the ceramic composite a good candidate as an indoor climate control heater, defogger device, kettle, and other heating element.

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CHARACTERIZATION AND ANALYSIS OF THE EFFECTS OF GREENHOUSE CLIMATE CONTROL EQUIPMENT ON GREENHOUSE MICROCLIMATE AND CROP RESPONSE

Acta Horticulturae ◽

10.17660/actahortic.2011.893.7 ◽

2011 ◽

pp. 117-132 ◽

Cited By ~ 3

Author(s):

C. Kittas ◽

N. Katsoulas ◽

T. Bartzanas

Keyword(s):

Crop Response ◽

Climate Control ◽

Greenhouse Climate ◽

Control Equipment ◽

Greenhouse Climate Control

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Indoor Airflow Distribution in Repository Design: Experimental and Numerical Microclimate Analysis of an Archive

Buildings ◽

10.3390/buildings11040152 ◽

2021 ◽

Vol 11 (4) ◽

pp. 152

Author(s):

Karin Kompatscher ◽

Rick P. Kramer ◽

Bart Ankersmit ◽

Henk L. Schellen

Keyword(s):

Vertical Gradient ◽

Building Envelope ◽

Cfd Modeling ◽

Indoor Climate ◽

Ambient Conditions ◽

Climate Control ◽

Climate Conditions ◽

Airflow Distribution ◽

Air Mixing ◽

Delay Variations

The majority of cultural heritage is stored in archives, libraries and museum storage spaces. To reduce degradation risks, many archives adopt the use of archival boxes, among other means, to provide the necessary climate control and comply with strict legislation requirements regarding temperature and relative air humidity. A strict ambient indoor climate is assumed to provide adequate environmental conditions near objects. Guidelines and legislation provide requirements for ambient indoor climate parameters, but often do not consider other factors that influence the near-object environment, such as the use of archival boxes, airflow distribution and archival rack placement. This study aimed to provide more insight into the relation between the ambient indoor conditions in repositories and the hygrothermal conditions surrounding the collection. Comprehensive measurements were performed in a case study archive to collect ambient, local and near-object conditions. Both measurements and computational fluid dynamics (CFD) modeling were used to research temperature/relative humidity gradients and airflow distribution with a changing rack orientation, climate control strategy and supply as well as exhaust set-up in a repository. The following conclusions are presented: (i) supplying air from one air handling unit to multiple repositories on different floors leads to small temperature differences between them. Differences in ambient and local climates are noticed; (ii) archival boxes mute and delay variations in ambient conditions as expected—however, thermal radiation from the building envelope may have a large influence on the climate conditions in a box; (iii) adopting night reduction for energy conservation results in an increased influence of the external climate, with adequate insulation, this effect should be mitigated; and (iv) the specific locations of the supply air and extraction of air resulted in a vertical gradient of temperature and insufficient mixing of air, and adequate ventilation strategies should enhance sufficient air mixing in combination with the insulation of external walls, and gradient forming should be reduced.

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