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Your search keyword '"Rozli Zulkifli"' showing total 3 results
Start Over Author "Rozli Zulkifli" Publisher hindawi limited
3 results on '"Rozli Zulkifli"'

1. Development of Pulsating Twin Jets Mechanism for Mixing Flow Heat Transfer Analysis

Author

Ali Ahmed Gitan, Rozli Zulkifli, Shahrir Abdullah, and Kamaruzzaman Sopian

Subjects
Technology, Medicine, Science
Abstract

Pulsating twin jets mechanism (PTJM) was developed in the present work to study the effect of pulsating twin jets mixing region on the enhancement of heat transfer. Controllable characteristics twin pulsed jets were the main objective of our design. The variable nozzle-nozzle distance was considered to study the effect of two jets interaction at the mixing region. Also, the phase change between the frequencies of twin jets was taken into account to develop PTJM. All of these factors in addition to the ability of producing high velocity pulsed jet led to more appropriate design for a comprehensive study of multijet impingement heat transfer problems. The performance of PTJM was verified by measuring the pulse profile at frequency of 20 Hz, where equal velocity peak of around 64 m/s for both jets was obtained. Moreover, the jet velocity profile at different pulsation frequencies was tested to verify system performance, so the results revealed reasonable velocity profile configuration. Furthermore, the effect of pulsation frequency on surface temperature of flat hot plate in the midpoint between twin jets was studied experimentally. Noticeable enhancement in heat transfer was obtained with the increasing of pulsation frequency.

Published
2014
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2. Characterization of a Bifacial Photovoltaic Panel Integrated with External Diffuse and Semimirror Type Reflectors

Author

P. Ooshaksaraei, Kamaruzzaman Sopian, Saleem H. Zaidi, M. A. Alghoul, and Rozli Zulkifli

Subjects
Materials science, Article Subject, Renewable Energy, Sustainability and the Environment, business.industry, lcsh:TJ807-830, Photovoltaic system, lcsh:Renewable energy sources, Reflector (antenna), General Chemistry, Atomic and Molecular Physics, and Optics, Light scattering, law.invention, Monocrystalline silicon, Electricity generation, Optics, law, Solar cell, Reflection (physics), Optoelectronics, General Materials Science, Wafer, business
Abstract

Silicon wafer accounts for almost one-half the cost of a photovoltaic (PV) panel. A bifacial silicon solar cell is attractive due to its potential of enhancing power generation from the same silicon wafer in comparison with a conventional monofacial solar cell. The bifacial PV cell is able to capture solar radiation by back surface. This ability requires a suitable reflector appropriately oriented and separated from the cell’s rear surface. In order to optimize the bifacial solar cell performance with respect to an external back surface reflector, diffuse and semimirror reflectors were investigated at various angles and separations from the back surface. A simple bifacial solar panel, consisting of four monocrystalline Si solar cells, was designed and built. Reflection from the rear surface was provided by an extended semimirror and a white-painted diffuse reflector. Maximum power generation was observed at 30° with respect to ground for the semimirror reflector and 10° for diffuse reflector at an optimized reflector-panel separation of 115 mm. Output power enhancement of 20% and 15% from semimirror and diffuse reflectors, respectively, were observed. This loss from diffuse reflector is attributed to scattering of light beyond the rear surface capture cross-section of the bifacial solar panel.

Published
2013

3. Characterization of Air-Based Photovoltaic Thermal Panels with Bifacial Solar Cells

Author

Rozli Zulkifli, P. Ooshaksaraei, Saleem H. Zaidi, and Kamaruzzaman Sopian

Subjects
Materials science, Silicon, Article Subject, Renewable Energy, Sustainability and the Environment, Photovoltaic system, lcsh:TJ807-830, lcsh:Renewable energy sources, chemistry.chemical_element, General Chemistry, Engineering physics, Laws of thermodynamics, Atomic and Molecular Physics, and Optics, Electricity generation, chemistry, Thermal, Exergy efficiency, General Materials Science, Wafer, First law of thermodynamics
Abstract

Photovoltaic (PV) panels account for a majority of the cost of photovoltaic thermal (PVT) panels. Bifacial silicon solar panels are attractive for PVT panels because of their potential to enhance electrical power generation from the same silicon wafer compared with conventional monofacial solar panels. This paper examines the performance of air-based bifacial PVT panels with regard to the first and second laws of thermodynamics. Four air-based bifacial PVT panels were designed. The maximum efficiencies of 45% to 63% were observed for the double-path-parallel bifacial PVT panel based on the first law of thermodynamics. Single-path bifacial PVT panel represents the highest exergy efficiency (10%). Double-path-parallel bifacial PVT panel is the second preferred design as it generates up to 20% additional total energy compared with the single-path panel. However, the daily average exergy efficiency of a double-path-parallel panel is 0.35% lower than that of a single-path panel.

Published
2013

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