Solar Radiation on Horizontal Tubular Microalgae Photobioreactor: Direct Beam Radiation

2011 ◽  
Vol 133 (2) ◽  
Author(s):  
T. Maor ◽  
J. Appelbaum

The solar irradiation on a photobioreactor plant for cultivating microalgae products such as dyes, vitamin, and biofuel is formulated, calculated, and verified. The outdoor solar plant consists of multiple horizontal tubes arranged in multiple vertical walls. The solar irradiation determines the growth rate of the algae; therefore, calculating the amount of solar radiation on the plant is important to estimate the production of microalgae. The incident direct beam irradiation on the tubes is calculated, taking into account tube and wall shading.

2011 ◽  
Vol 133 (2) ◽  
Author(s):  
T. Maor ◽  
J. Appelbaum

Different view factors and different components of the diffuse solar radiation impinging on a photobioreactor plant for cultivating microalgae products are formulated and calculated in the present article. The outdoor plant consists of multiple horizontal tubes arranged in multiple vertical walls. The diffuse radiation on a tube may come from three directions of the sky: from the aperture between the walls (from the sky above), from the penetration of the diffuse radiation between the tubes, and from the plant edges. Each component of the diffuse radiation is associated with a different view factor. For design parameters of a practical plant, the largest component of the diffuse radiation comes from the sky above the plant.


Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1865
Author(s):  
Bala Bhavya Kausika ◽  
Wilfried G. J. H. M. van Sark

Geographic information system (GIS) based tools have become popular for solar photovoltaic (PV) potential estimations, especially in urban areas. There are readily available tools for the mapping and estimation of solar irradiation that give results with the click of a button. Although these tools capture the complexities of the urban environment, they often miss the more important atmospheric parameters that determine the irradiation and potential estimations. Therefore, validation of these models is necessary for accurate potential energy yield and capacity estimations. This paper demonstrates the calibration and validation of the solar radiation model developed by Fu and Rich, employed within ArcGIS, with a focus on the input atmospheric parameters, diffusivity and transmissivity for the Netherlands. In addition, factors affecting the model’s performance with respect to the resolution of the input data were studied. Data were calibrated using ground measurements from Royal Netherlands Meteorological Institute (KNMI) stations in the Netherlands and validated with the station data from Cabauw. The results show that the default model values of diffusivity and transmissivity lead to substantial underestimation or overestimation of solar insolation. In addition, this paper also shows that calibration can be performed at different time scales depending on the purpose and spatial resolution of the input data.


2012 ◽  
Vol 48 (2) ◽  
pp. 382-386 ◽  
Author(s):  
Juan Aguirre ◽  
Mª Rosa Rodríguez ◽  
Rodrigo González ◽  
Gonzalo García de Fernando

2004 ◽  
Vol 126 (3) ◽  
pp. 906-914 ◽  
Author(s):  
David Faiman ◽  
Daniel Feuermann ◽  
Peter Ibbetson ◽  
Bryan Medwed ◽  
Amos Zemel ◽  
...  

We present a summary of the principal findings in an ongoing, multiyear, survey of the solar radiation resource and associated meteorological parameters in Israel’s Negev Desert. The summary addresses calibration and monitoring issues, the format in which the annual results are published, availability of the data, and some of the more interesting results observed to date. In particular, we quantify the large variability observed in the direct beam radiation across neighboring sites. The year-to-year variation in this radiation component is also considerable. The variation in the global horizontal radiation is much smaller. Two practical examples are given of uses to which the Negev Radiation Survey has been put: Site selection for a proposed 500 MW solar-thermal power plant; and an estimation of the potential photovoltaic value of rooftops in the major cities.


Author(s):  
Basma Ghazal ◽  
Saad Makhseed

Novel composites of zinc oxide (ZnO) and copper phthalocyanines (CuTriPc and CuPc) were synthesized as efficient natural solar light photocatalysts for the photodegradation of organic wastewater pollutants. Spectroscopic and analytical measurements confirmed that both bulky triazolo copper phthalocyanine (CuTriPc) and unsubstituted planer (CuPc) were successfully coupled with ZnOnanoparticles. The synthesized nanocomposites were investigated as natural solar radiation photocatalysts toward the photodegradation of methylene blue (MB) analogue dye. The prepared CuTriPc/ZnO nanocomposite was proven to be an efficient solar light photocatalyst compared to pure ZnO and the unsubstituted CuPc/ZnO.


2020 ◽  
Vol 865 ◽  
pp. 19-24
Author(s):  
Shane C. Halligan ◽  
Kieran A. Murray ◽  
Olivier Vrain ◽  
John G. Lyons ◽  
Luke M. Geever

Exposing smart materials to electron beam radiation can induce free radical reactions, such as chain branching or crosslinking, hence enhancing the characteristics of the polymers. Poly (N-vinylcaprolactam) (PNVCL) is a smart material which was synthesised by photopolymerisation. Subsequently, samples were exposed to electron beam technology, where electron beam irradiation was utilised in a novel approach. This led to the modification of the rheological and phase transition properties. Modifying PNVCL through electron beam irradiation opens new avenues and potential applications in the biomedical field. Physically cross-linked PNVCL polymers were prepared by photopolymerisation and samples were subsequently irradiated at different dose ranges (5kGy, 25kGy and 50 kGy). The rheological properties of the PNVCL based samples were established by rheological analysis. Similarly, the PNVCL based sample polymers were further characterised in solution to determine the phase transition of PNVCL.


2020 ◽  
Vol 1002 ◽  
pp. 57-65
Author(s):  
Abdulkader M. Alakrach ◽  
Nik Noriman Zulkepli ◽  
Awad A. Al-Rashdi ◽  
Sam Sung Ting ◽  
Rosniza Hamzah ◽  
...  

This study aimed to develop novel Polylactic acid/ Halloysite (PLA/ HNTs) films which showed better properties when they were used for food packaging. They also displayed better mechanical, barrier, morphological and structural properties when the researchers analysed the impact of the electron beam irradiation on the nanomaterials. They prepared PLA-based nanocomposites containing 5 % w/w of HNTs using the solution casting process. These nanocomposites were further exposed to different ebeam doses (i.e., 0, 20, 40 and 60 kGy). The researchers assessed the effect of the electron beam irradiation on the various properties of the PLA. All the composites showed a homogenous dispersion and distribution of the HNTs in this PLA matrix. Results indicated that the nanocomposites showed better barrier properties in comparison to the neat PLA. Furthermore, the ebeam irradiation could increase the glass-transition temperature and lead to the development of more crosslinks, which increased the degradation temperature and hydrophilicity of the nanocomposites. In this study, the researchers showed that the PLA/HNTs films were effective materials that could be used for the electron beam processing of the pre-packed foods. The best effect was noted for the 20 kGy dosage which was used in the study.


2019 ◽  
Vol 11 (22) ◽  
pp. 6443 ◽  
Author(s):  
Hailu ◽  
Fung

We present a study conducted to obtain optimum tilt angle and orientation of a solar panel for the collection of maximum solar irradiation. The optimum tilt angle and orientation were determined using isotropic and anisotropic diffuse sky radiation models (isotropic and anisotropic models). The four isotropic models giving varying optimum tilt angles in the range of 37 to 44°. On the other hand, results of the four anisotropic models were more consistent, with optimum tilt angles ranging between 46–47°. Both types of models indicated that the collector tilt should be changed four times a year to receive more solar radiation. The results also indicate that the solar panel should be installed with orientation west or east of due south with a flatter tilt angle. A 15° change in orientation west or east of due south results in less than 1% reduction of the total solar radiation received. For a given optimum tilt angle, the effect of photovoltaic/thermal (PV/T) orientation west or east of due south on the outlet temperature was determined using a one-dimensional steady state heat transfer model. It was found that there is less than 1.5% decrease in outlet temperature for a PV/T panel oriented up to 15° east or west of due south from March to December. This result indicates that existing roofs with orientations angles up to 15° east or west of due south can be retrofitted with a PV/T system without changing the roof shape.


1977 ◽  
Vol 4 (4) ◽  
pp. 485 ◽  
Author(s):  
S Fukai ◽  
JH Silsbury

Small swards of subterranean clover were grown at 20°C at different times of the year and at the same time under shades of different light transmission. Dry matter production and net CO2 exchange rates at different levels of irradiance were measured during growth. Crop growth rates and net CO2 exchange rates are examined in relation to plant attributes and to the daily solar radiation. Dry matter growth curves varied according to the daily solar radiation. Increase in crop growth rate with increase in daily solar radiation was taken to be linear for swards with similar dry weight and was more rapid for closed canopies than for those not showing full light interception. Once a closed canopy was attained, further increase in total dry matter resulted in decreased crop growth rate due, apparently, to increased loss of dry weight through increased respiration rate. The shape of the CO2 exchange/irradiance curve was linear up to 100 W m-2 (PAR) and curvilinear above that value. The rate of net CO2 exchange at 50 W m-2 (PAR) decreased with increase in shoot dry matter above 100 g m-2 due, apparently, to an increased rate of dark CO2 efflux: the rate was not affected by daily solar radiation during growth. The net CO2 exchange rate at 250 W m-2 (PAR) increased with increase in LAI up to 3 after which it became almost constant, varying only with the variation in daily solar radiation during growth. The rate of dark CO2 efflux was strongly affected by the amount of dry matter present and to a smaller extent by the crop growth rate or the daily solar radiation.


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