Browsing by Author "Kareem, M.W"

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    Effect of air gap on perfomance enhancement of building assisted with photo voltaic systems
    (ARPN Journal of Engineering and Applied Sciences, 2016-10-10) Kashif Irshad; Khairul Habib; Kareem, M.W
    This paper investigates performance improvement of room assisted with Photo voltaic (PV) system by varying air gap and PV glazing type. PV panel was installed on the south side of the room as Photo Voltaic Trombe wall (PV-TW) and over the roof. Performance was evaluated in term of cooling load, energy consumption and PV efficiency. Three different types of PV glazing (i.e. Single Glazing, Double glazing, double glazing filled with Argon gas) was tested by changing air gap between wall and PV panel for Malaysian climate. TRNSYS building simulation software was used in which various input parameters were inserted to obtain the results. It was found that maximum PV efficiency was achieved in the case of Double glass filled with Argon PV-TW at air gap of 0.2 m and roof pitch angle 20 degree. Ventilated PV-TW and PV panel installed over the roof also reduces cooling load of the room. Among all the three types of glazing, room assisted with Double glass filled with argon PV panel shows highest reduction in cooling load at air gap 0.2m and roof pitch angle 20 degree. Also cooling load of room reduced significantly with the increase in roof pitch angle up to certain critical angle which is different for different PV glazing.
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    Numerical modelling of multi-pass solar dryer filled with granite pebbles for thermal storage enhancement
    (IOP Conf. Series: Materials Science and Engineering, 2015-04-03) Kareem, M.W; K. Habib; M.H. Ruslan
    In this paper, a theoretical modelling of a cheap solar thermal dryer for small and medium scale farmers with multi-pass approach has been investigated. Comsol Multiphysics modelling tool was employed using numerical technique. The rock particles were used to enhance the thermal storage of the drying system. The local weather data were used during the simulation while parameters and coefficients were sourced from literature. An improvement on efficiency of up to 7% was recorded with error of 10-5 when compared with the reported double pass solar collector. A fair distribution of hot air within the cabinets was also achieved. Though the modelling tool used was robust but the characterization of the system materials need to be done to improve the system accuracy and better prediction.
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    Thermal performance study of a multi-pass solar air heating collector system for drying of Roselle (Hibiscus sabdariffa)
    (Elsevier, 2017-08-12) Kareem, M.W; Khairul Habib; Ruslan M.H; Bidyut Baran Saha
    This article presents a study on the performance of a forced convective multi-pass solar air heating collector (MPSAHC) system assisted with granite as a sensible energy storing matrix. Experimental drying of Roselle was carried out in August 2015 at Solar Energy Research Site of Universiti Teknologi PETRONAS, Malaysia (4.385693 N and 100.979203 S). The present investigation was conducted under the daily average relative humidity, solar irradiance, ambient temperature and wind speed of 64.5%, 635.49 Wm 2, 32.24 C, and 0.81 ms 1, respectively. An average drying rate of 33.57 g (kg m2 h) 1 was achieved while the system optical efficiency, collector efficiency, drying efficiency and moisture pickup efficiency of 70.53%, 64.08%, 36.22% and 66.95% were obtained, respectively. MPSAHC dryer was 21 h faster with fair color retention when compared to open sun drying approach (OSDA) that was conducted together under the same weather condition. Techno economic analysis reflected a payback period of 2.14 years. However, drying efficiency could be improved if the inlet air humidity can be controlled to favor drying operation.