Design of a Micro-Probe For Direct Measurement of Convection Heat Transfer on a Vertical Building Integrated Photovoltaic (BIPV)
A proximity probe with two k-type thermocouples, 1.5 mm apart, was designed, built to simultaneously measure local surface and air temperatures on the PV and to quantify local convention heat transfer coefficient. Experimental investigations of natural convection on a vertical photovoltaic (PV) panel exposed to solar radiations are presented. The variation of non-isothermal surface temperature of a PV is expressed with a second-order polynomial relation. In the absence of any correlation to predict the natural convection heat transfer coefficient on a PV, experimental results are presented in the form of variations of the local Nusselt numbers (Nuz), and the average Nusselt numbers (Nu), with Rayleigh number (Ra). The variations are best expressed with a power law correlation form of Nu=a*(Ra)b for the range 106<Ra <108 where a and b are determined experimentally. The power-law correlations for photovoltaic were compared with a number of correlations developed from natural convection research in laboratories. The analysis showed that for a given Rayleigh number, the predicted value of Nusselt number by the PV correlations are within the range covered by others. However, the PV correlations overestimate the Nusselt number by 20% in Rayleigh number higher than 106. The work is in progress to further extend the correlation to predict the combined radiation and convection on all PV configurations, as required in the efficient design of building integrated photovoltaic (BIPV) systems.
Madadnia, J. Dehestani, D. Mehta, A. Vakiloroaya, V. Koosha, H.
Faculty of Engineering & IT, University of Technology Sydney P.O.Box 123, Broadway, NSW 2007, Australia
国际会议
The 4th International Conference on Mechanical Engineering and Mechanics(第四届国际机械工程与力学会议)
苏州
英文
817-824
2011-08-11（万方平台首次上网日期，不代表论文的发表时间）