RESEARCH CONCERNING THE PERFORMANCE OF THE TINOX SELECTIVE COATINGS OF THE SOLAR COLLECTORS

The present paper presents the results of the experimental research achieved in refference to a solar thermal system for domestic water heating, installed in the city of Arad qat. 46.19 degrees N; long. 21.31 degrees E) [7], [9]. Thus the behaviour of the TiNOX type selective coatings, that is part in the componence of the vacuum tube solar collectors, working under the solar radiation action with a length wave in the visible domain, was studied (lambda=0.38-0.78 mu m), [1], [5]. The experimental results show the time variation of the monitorized parametres, in December 2006 - July 2008: illumination E(lx) and the temperature of the thermal agent used T(2) (degrees C) in the condenser-collector, in which the vacuum tubes are mounted. The used measurement and monitorizing instruments acting on the experimental pilot exposed in real conditions, the Extech model 401036 luxmeter, the process installation calculator and the PC were proper used in order to demonstrate that, under given conditions, lm(2) of absorbant made of selective TiNOX coatings, produces a thermical flux of 0.781 kW, by mentaining the recovered energy over one and half of a day of use of needed parameters (temperatures especially).