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The study of thermal and ventilation parameters, obtained in a transient, laminar solar chimney of reduced dimensions, (1 < m <3) m with a square collector (side = 2m) is presented. Experimental measurements has been made to determine the temperature of the absorber and the fluid in the collector, it is shown that at the entrance of the chimney, the temperature of the absorber decreases slightly while that of the fluid is maintained at a maximum level. Temperature differences were observed up to 32°C between the atmosphere and the fluid in April. A temperature variation at the absorber depending on the stack height is presented. Temperature measurements in the chimney, at various heights depending on the axial coordinate, show a variable temperature profile. It is, from these, shown that, in the selected interval of stack height, the average speeds of output increase linearly as a function of stack height. For a chimney of 3m in height and 20cm in diameter, a maximum speed of approximately 0.7 ms -1 was observed. The lack of appropriate equipment handicaps the velocity measurement at the chimney entrance. Thus, the results of simulations with the computer code COMSOL 5.1 has confirmed temperature values measured at the chimney entrance and after this, velocity values are determined.

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We present in this paper, a craft prototype of a fixed hemispheric concentrator, built from small square mirrors with a moon crescent receiver. The position of the receiver is adjusted every three days taking into account the declination. This system achieves a geometric mean concentration of 122 and the experimental measurements lead to temperatures varying between 120°C and 260°C in the plan for the least diffusion. The proposed improvements should allow for more competitiveness and convenience than the Scheffler system with its electromechanical sun tracking.