Effect of Shape, Orientation and Aging of a Plastic Greenhouse Cover on the Degradation Rate of the Optical Properties in Arid Climates
In arid climates, the optical properties of plastic-covered greenhouses deteriorate very quickly. To examine the effect of greenhouse shape and orientation on the degradation rate of cover optical properties, four greenhouse prototypes were constructed in two shapes (duo-pitched roof and tunnel), co...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-03-01
|
| Series: | Applied Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2076-3417/12/5/2709 |
| _version_ | 1797475557631328256 |
|---|---|
| author | Ibrahim Al-Helal Pietro Picuno Abdullah A. Alsadon Abdullah Ibrahim Mohamed Shady Ahmed M. Abdel-Ghany |
| author_facet | Ibrahim Al-Helal Pietro Picuno Abdullah A. Alsadon Abdullah Ibrahim Mohamed Shady Ahmed M. Abdel-Ghany |
| author_sort | Ibrahim Al-Helal |
| collection | DOAJ |
| description | In arid climates, the optical properties of plastic-covered greenhouses deteriorate very quickly. To examine the effect of greenhouse shape and orientation on the degradation rate of cover optical properties, four greenhouse prototypes were constructed in two shapes (duo-pitched roof and tunnel), covered with a 200 µm thick low-density polyethylene film. Two types were oriented in the North–South direction, the other two in the East–West direction, and all were exposed for one year to an arid climate. Samples were taken from the different surfaces of each cover for testing. The total transmittance (<i>T</i><sub>s</sub>) and reflectance (<i>R</i><sub>s</sub>) of the samples were measured and averaged to obtain the whole cover properties (<i>T</i> and <i>R</i>). Measurements were carried out periodically every 30 days for the four prototypes. The degradation behavior of the optical properties of each cover surface (<i>T</i><sub>s</sub>, <i>R</i><sub>s</sub>) and the whole cover (<i>T</i>, <i>R</i>) was investigated for the four film covers during the exposure time. Results show that the degradation rate of <i>T</i><sub>s</sub> depends on the surface location and the cover orientation. Among the different surfaces of the four prototype covers, the maximum difference in the <i>T</i><sub>s</sub> value between the E and N surfaces for the tunnel cover oriented in the N–S direction was 15.5%. Although the variation of the <i>T</i><sub>s</sub> value among the different cover surfaces was found, the time dependences of the whole cover transmittance (<i>T</i>) for the four covers tested were almost similar. Accordingly, the shape and orientation of the small size greenhouses did not significantly affect the degradation rate of the cover optical properties. In the four covers tested, the reduction in the global solar radiation transmittance (<i>T</i>) was 27–31% after one-year exposure compared to the new film. Nonlinear correlation was developed to predict the degradation rate of the cover transmittance as a function of the accumulated solar irradiance. |
| first_indexed | 2024-03-09T20:46:49Z |
| format | Article |
| id | doaj.art-8db579b7ceca4bc6b0fd89de0f5f28ef |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-09T20:46:49Z |
| publishDate | 2022-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-8db579b7ceca4bc6b0fd89de0f5f28ef2023-11-23T22:45:05ZengMDPI AGApplied Sciences2076-34172022-03-01125270910.3390/app12052709Effect of Shape, Orientation and Aging of a Plastic Greenhouse Cover on the Degradation Rate of the Optical Properties in Arid ClimatesIbrahim Al-Helal0Pietro Picuno1Abdullah A. Alsadon2Abdullah Ibrahim3Mohamed Shady4Ahmed M. Abdel-Ghany5Department of Agricultural Engineering, College of Food and Agriculture Sciences, King Saud University, Riyadh 11451, Saudi ArabiaSAFE School, University of Basilicata, 85100 Potenza, ItalyDepartment of Plant Production, College of Food and Agriculture Sciences, King Saud University, Riyadh 11451, Saudi ArabiaDepartment of Plant Production, College of Food and Agriculture Sciences, King Saud University, Riyadh 11451, Saudi ArabiaDepartment of Agricultural Engineering, College of Food and Agriculture Sciences, King Saud University, Riyadh 11451, Saudi ArabiaDepartment of Agricultural Engineering, College of Food and Agriculture Sciences, King Saud University, Riyadh 11451, Saudi ArabiaIn arid climates, the optical properties of plastic-covered greenhouses deteriorate very quickly. To examine the effect of greenhouse shape and orientation on the degradation rate of cover optical properties, four greenhouse prototypes were constructed in two shapes (duo-pitched roof and tunnel), covered with a 200 µm thick low-density polyethylene film. Two types were oriented in the North–South direction, the other two in the East–West direction, and all were exposed for one year to an arid climate. Samples were taken from the different surfaces of each cover for testing. The total transmittance (<i>T</i><sub>s</sub>) and reflectance (<i>R</i><sub>s</sub>) of the samples were measured and averaged to obtain the whole cover properties (<i>T</i> and <i>R</i>). Measurements were carried out periodically every 30 days for the four prototypes. The degradation behavior of the optical properties of each cover surface (<i>T</i><sub>s</sub>, <i>R</i><sub>s</sub>) and the whole cover (<i>T</i>, <i>R</i>) was investigated for the four film covers during the exposure time. Results show that the degradation rate of <i>T</i><sub>s</sub> depends on the surface location and the cover orientation. Among the different surfaces of the four prototype covers, the maximum difference in the <i>T</i><sub>s</sub> value between the E and N surfaces for the tunnel cover oriented in the N–S direction was 15.5%. Although the variation of the <i>T</i><sub>s</sub> value among the different cover surfaces was found, the time dependences of the whole cover transmittance (<i>T</i>) for the four covers tested were almost similar. Accordingly, the shape and orientation of the small size greenhouses did not significantly affect the degradation rate of the cover optical properties. In the four covers tested, the reduction in the global solar radiation transmittance (<i>T</i>) was 27–31% after one-year exposure compared to the new film. Nonlinear correlation was developed to predict the degradation rate of the cover transmittance as a function of the accumulated solar irradiance.https://www.mdpi.com/2076-3417/12/5/2709optical propertiessolar radiationplastic filmsgreenhouse coverdegradationarid climate |
| spellingShingle | Ibrahim Al-Helal Pietro Picuno Abdullah A. Alsadon Abdullah Ibrahim Mohamed Shady Ahmed M. Abdel-Ghany Effect of Shape, Orientation and Aging of a Plastic Greenhouse Cover on the Degradation Rate of the Optical Properties in Arid Climates Applied Sciences optical properties solar radiation plastic films greenhouse cover degradation arid climate |
| title | Effect of Shape, Orientation and Aging of a Plastic Greenhouse Cover on the Degradation Rate of the Optical Properties in Arid Climates |
| title_full | Effect of Shape, Orientation and Aging of a Plastic Greenhouse Cover on the Degradation Rate of the Optical Properties in Arid Climates |
| title_fullStr | Effect of Shape, Orientation and Aging of a Plastic Greenhouse Cover on the Degradation Rate of the Optical Properties in Arid Climates |
| title_full_unstemmed | Effect of Shape, Orientation and Aging of a Plastic Greenhouse Cover on the Degradation Rate of the Optical Properties in Arid Climates |
| title_short | Effect of Shape, Orientation and Aging of a Plastic Greenhouse Cover on the Degradation Rate of the Optical Properties in Arid Climates |
| title_sort | effect of shape orientation and aging of a plastic greenhouse cover on the degradation rate of the optical properties in arid climates |
| topic | optical properties solar radiation plastic films greenhouse cover degradation arid climate |
| url | https://www.mdpi.com/2076-3417/12/5/2709 |
| work_keys_str_mv | AT ibrahimalhelal effectofshapeorientationandagingofaplasticgreenhousecoveronthedegradationrateoftheopticalpropertiesinaridclimates AT pietropicuno effectofshapeorientationandagingofaplasticgreenhousecoveronthedegradationrateoftheopticalpropertiesinaridclimates AT abdullahaalsadon effectofshapeorientationandagingofaplasticgreenhousecoveronthedegradationrateoftheopticalpropertiesinaridclimates AT abdullahibrahim effectofshapeorientationandagingofaplasticgreenhousecoveronthedegradationrateoftheopticalpropertiesinaridclimates AT mohamedshady effectofshapeorientationandagingofaplasticgreenhousecoveronthedegradationrateoftheopticalpropertiesinaridclimates AT ahmedmabdelghany effectofshapeorientationandagingofaplasticgreenhousecoveronthedegradationrateoftheopticalpropertiesinaridclimates |