scholarly journals Two-Axis Solar Heat Collection Tracker System for Solar Thermal Applications

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Tsung-Chieh Cheng ◽  
Wei-Cheng Hung ◽  
Te-Hua Fang
Keyword(s):  
Experimental Study ◽  
Focal Length ◽  
Polar Axis ◽  
Fresnel Lens ◽  
Heat Energy ◽  
Power Measurement ◽  
Solar Irradiation ◽  
The Sun ◽  
Solar Heat ◽  
Solar Thermal Applications

An experimental study was performed to investigate the effect of using a continuous operation two-axes tracking on the solar heat energy collected. This heat-collection sun tracking which LDR (light dependent resistor) sensors installed on the Fersnel lens was used to control the tracking path of the sun with programming method of control with a closed loop system. The control hardware was connected to a computer through Zigbee wireless module and it also can monitor the whole tracking process information on a computer screen. An experimental study was performed to investigate the effect of using two-axes tracking on the solar heat energy collected. The results indicate that sun tracking systems are being increasingly employed to enhance the efficiency of heat collection by polar-axis tracking of the sun. Besides, the heating power was also measured by designed power measurement module at the different focal length of Fresnel lens, and the design of shadow mask of LDR sensors is an important factor for solar photothermal applications. Moreover, the results also indicated that the best time to obtain the largest solar irradiation power is during 11:00 –13:00  in Taiwan.

scholarly journals Experimental Investigation on the Feasibility of Using a Fresnel Lens as a Solar-Energy Collection System for Enhancing On-Orbit Power Generation Performance

2017 ◽  
Vol 2017 ◽  
pp. 1-13
Author(s):  
Tae-Yong Park ◽  
Joo-Yong Jung ◽  
Hyun-Ung Oh
Keyword(s):  
Power Generation ◽  
Solar Energy ◽  
Attitude Control ◽  
Incidence Angle ◽  
Fresnel Lens ◽  
Power Measurement ◽  
The Sun ◽  
Solar Panels ◽  
Collection System ◽  
Power Generation Performance

Cube satellites have a limitation for generating power because of their cubic structure and extremely small size. In addition, the incidence angle between the sun and the solar panels continuously varies owing to the revolution and rotation of the satellite according to the attitude control strategy. This angle is an important parameter for determining the power generation performance of the cube satellite. In this study, we performed an experimental feasibility study that uses a Fresnel lens as a solar-energy collection system for cube satellite applications, so that the power generation efficiency can be enhanced under the worst incidence angle condition between the sun and solar panels by concentrating and redirecting solar energy onto the solar panels with a commercial Fresnel lens. To verify the effectiveness of the proposed system, we conducted a power-measurement test using a solar simulator and Fresnel lenses at various angles to the light source. In addition, we predicted the on-orbit power-generation enhancement achieved by employing the solar-energy collection system with various attitude control strategies.

Experimental Study on a Passive Solar Desalination Unit Associated With Fresnel Lens and Thermal Storage

2021 ◽  
Author(s):  
Jun-Yan Tan ◽  
Jun Wei Ding ◽  
Zhi Yong Ho ◽  
Rubina Bahar
Keyword(s):  
Experimental Study ◽  
Saline Water ◽  
Low Cost ◽  
Fresnel Lens ◽  
Solar Irradiation ◽  
Petroleum Jelly ◽  
Solar Desalination ◽  
Passive Solar ◽  
Tropical Weather ◽  
The Individual

Abstract Passive solar stills can be a viable source of freshwater in water and energy scarce regions. However, the low production rate is one of the major drawbacks of passive solar stills. This work presents an experimental study of the combined effects of concentrated solar power (CSP) and phase change material (PCM) on a low-cost double slope passive solar desalination unit. Fresnel lens as the refractive CSP was used to converge the available solar irradiation onto the solar still basin that contained saline water. Metal tubes containing petroleum jelly with a melting point of 37°C were immersed as the PCM in the saline water. Four different experimental setups were tested in the natural tropical weather of Malaysia to identify the individual and combined impact of the lens and petroleum jelly on desalination performance. It was observed that the performance was better with the individual application of the CSP rather than the combination of CSP and PCM. There was a 28.21 % improvement in distillate production using Fresnel lens only; while using the Fresnel lens and PCM in combination showed a 25.64 % improvement in production. This study also provides several recommendations with which the experimental setup can be improved to yield better results in the future.

scholarly journals Simulation and Experimental Study on the Optical Performance of a Fixed-Focus Fresnel Lens Solar Concentrator Using Polar-Axis Tracking

Energies ◽  
2018 ◽  
Vol 11 (4) ◽  
pp. 887 ◽  
Author(s):  
Hai Wang ◽  
Jin Huang ◽  
Mengjie Song ◽  
Yanxin Hu ◽  
Yunfeng Wang ◽  
...  
Keyword(s):  
Experimental Study ◽  
Polar Axis ◽  
Fresnel Lens ◽  
Solar Concentrator ◽  
Optical Performance

scholarly journals Innovative Solar Tracking Concept by Rotating Prism Array

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Héctor García ◽  
Carlos Ramírez ◽  
Noel León
Keyword(s):  
Solar Radiation ◽  
Solar Energy ◽  
Polymethyl Methacrylate ◽  
Negative Impact ◽  
Fresnel Lens ◽  
Simulation Software ◽  
The Sun ◽  
System Efficiency ◽  
Solar Tracking ◽  
Solar Thermal Applications

Solar energy has become one of the most promising renewable energies and is the most widely used nowadays. In order to achieve an optimum performance, both photovoltaic and solar thermal applications are required to track the position of the sun throughout the day and year in the most effective way possible to avoid a high negative impact on the system efficiency. The present paper attempts to describe a novel semipassive solar tracking concentrator (SPSTC) in which, in order to track the sun, two independent arrays of polymethyl methacrylate (PMMA) prisms are implemented to refract sunlight by rotating said prisms, thus being able to redirect solar radiation as desired. The first set is responsible for eliminating one of the directional components of the solar radiation; the task is achieved by rotating the prisms within the array at a specific angle. The second set deals with another of the sunlight’s directional components, transforming its direction into a completely perpendicular pattern to the array. Having downward vertical radiation makes it possible to implement a stationary Fresnel lens to concentrate the solar radiation for any application desired. The system is designed and validated using simulation software to prove the feasibility of the concept.

scholarly journals Increasing Solar Energy Usage for Dwelling Heating, Using Solar Collectors and Medium Sized Vacuum Insulated Storage Tank

Energies ◽  
2018 ◽  
Vol 11 (7) ◽  
pp. 1832 ◽  
Author(s):  
Janar Kalder ◽  
Andres Annuk ◽  
Alo Allik ◽  
Eugen Kokin
Keyword(s):  
Heat Pump ◽  
Storage Tank ◽  
Storage System ◽  
Heating System ◽  
Heat Energy ◽  
Solar Irradiation ◽  
Water Tank ◽  
Energy Usage ◽  
Solar Heat ◽  
Direct Heating

This article describes a method for increasing the solar heat energy share in the heating of a dwelling. Solar irradiation is high in summer, in early autumn, and in spring, but during that same time, the heat demand of dwellings is low. This article describes a solution for storing solar heat energy in summertime as well as the calculations of the heat energy balance of such a storage system. The solar heat energy is stored in a thermally insulated water tank and used in the heating period. The heat is also stored in the ground if necessary, using the ground loop of the heat pump if the water tank’s temperature rises above a certain threshold. The stored heat energy is used directly for heating if the heat carrier temperature inside the tank is sufficient. If the temperature is too low for direct heating, then the heat pump can be used to extract the stored energy. The calculations are based on the solar irradiation measurements and heating demand data of a sample dwelling. The seasonal storing of solar heat energy can increase the solar heat energy usage and decrease the heat pump working time. The long-term storage tank capacity of 15 m3 can increase the direct heating from solar by 41%. The direct heating system efficiency is 51%.

scholarly journals Analysis and Optimization of a Novel Hexagonal Waveguide Concentrator for Solar Thermal Applications

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2146
Author(s):  
Karunesh Kant ◽  
Karthik Nithyanandam ◽  
Ranga Pitchumani
Keyword(s):  
Industrial Process ◽  
Cost Effective ◽  
Solar Irradiation ◽  
Maintenance Cost ◽  
Solar Concentrator ◽  
Thermal Desalination ◽  
Process Heat ◽  
Solar Thermal Applications ◽  
The Cost ◽  
Operation And Maintenance Cost

This paper analyzes a novel, cost-effective planar waveguide solar concentrator design that is inspired by cellular hexagonal structures in nature with the benefits of facile installation and low operation and maintenance cost. A coupled thermal and optical analysis of solar irradiation through an ideal hexagonal waveguide concentrator integrated with a linear receiver is presented, along with a cost analysis methodology, to establish the upper limit of performance. The techno-economic model, coupled with numerical optimization, is used to determine designs that maximized power density and minimized the cost of heat in the temperature range of 100–250 °C, which constitutes more than half of the industrial process heat demand. Depending on the incident solar irradiation and the application temperature, the cost of heat for the optimal design configuration ranged between 0.1–0.27 $/W and 0.075–0.18 $/W for waveguide made of ZK7 glass and polycarbonate, respectively. A techno-economic analysis showed the potential of the technology to achieve cost as low as 80 $/m2 and 61 $/m2 for waveguide made of ZK7 glass and polycarbonate material, respectively, which is less than half the cost of state-of-the-art parabolic trough concentrators. Overall, the hexagonal waveguide solar concentrator technology shows immense potential for decarbonizing the industrial process heat and thermal desalination sectors.

Brief Acupuncture Treatment for Dermatitis Solaris: A Multicentre Pilot Study

1992 ◽  
Vol 10 (2) ◽  
pp. 64-65
Author(s):  
Raymund Pothmann
Keyword(s):  
Pilot Study ◽  
Acute Treatment ◽  
Acupuncture Treatment ◽  
Heat Energy ◽  
The Sun ◽  
Dermatitis Solaris

The conventional dermatological therapy for urticaria solaris is often problematic in practice. Acute treatment is rarely successful; avoidance of exposure to the sun is isolating for the patient; and prophylaxis is too prolonged or unsafe. According to traditional Chinese pathogenic understanding, acupuncture seems to be the treatment of choice for improving symptoms of superficial heat energy. A maximum of 3 sessions over 3 days using acupoints L1.11 and SP.10 led to significant improvement of acute symptoms within 2 days. This treatment was effective for several weeks, including exposure to the sun, for all 4 patients observed over the whole season. Thus acupuncture should be integrated in the dermatological treatment of so-called solar allergy.

THE COSMIC JOURNEY OF ODYSSEUS

Numen ◽  
2001 ◽  
Vol 48 (4) ◽  
pp. 381-416 ◽  
Author(s):  
Nanno Marinatos
Keyword(s):  
Iron Age ◽  
Mediterranean Region ◽  
Near East ◽  
British Museum ◽  
Polar Axis ◽  
The Sun ◽  
East Mediterranean ◽  
The Earth ◽  
The Universe ◽  
East Mediterranean Region

AbstractIn vain have scholars tried to produce a coherent geographical picture of Odysseus' travels. It is argued here that Odysseus makes a cosmic journey at the edges of the earth (perata ges), a phrase used in the text to describe several lands that the hero visits. The cosmic journey was a genre current in the East Mediterranean region in the Iron Age. It was modeled on the Egyptian the journey of the sun god who travels twelve hours in the darkness of the underworld and twelve hours in the sky. Evidence of similar concepts in the Near East is provided by a Babylonian circular map (now in the British Museum) as well as by Phoenician circular bowls. Gilgamesh seems to perform a cosmic journey. As well, Early Greek cosmology utilizes the concept of a circular cosmos. Odysseus' journey spans the two cosmic junctures of the universe: East, where Circe resides, and West, where Calypso lives. Another polar axis is the underworld and the island of the sun.

scholarly journals An experimental study of solar cooker performance with thermal concentrator system by spot Fresnel lens

2020 ◽  
Vol 5 (8 (107)) ◽  
pp. 31-41
Author(s):  
Asrori Asrori ◽  
Sudjito Suparman ◽  
Slamet Wahyudi ◽  
Denny Widhiyanuriyawan
Keyword(s):  
Experimental Study ◽  
Fresnel Lens
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