The aim of this study was to establish the basic discharge characteristics of belt control laboratory sample, depending on water level in the upstream and the opening of the flow cross section of seat of belt controller. The experiment was conducted in accordance with the program of the central compositional planning (CCU) of the second order in the hydraulic laboratory of the University. Hydraulic tray with 7.0 m lengh long, 0.6 m wide and 0.8 m deep was overlapped with contiguous control structure. Belt regulator model 100 × 100 mm was mounted at a height of 0.24 m from the bottom of the pan. The main flow of regulator was measured with a calibrated (gauged) trapezoidal weir, and the flow of the control chamber was measured with volumetric method with preliminary use of calibrated flowmeter and a stopwatch. Screening of gross errors was made by the calculation method of maximum relative deviation and normality of experimental data distribution was evaluated previously by varying scope. Dispersion analysis was done by Matcad. Still this response function was approximated by a quadric polynomial, the statistical significance of the regression equation coefficients was tested by Student's t test, and the adequacy of the model obtained – by the Fisher test. On the basis of an adequate model the graphs of the surface of response function using wxMaxima program as well as level curve graphics and sections of the response surface were built. An analysis of regression equations and graphs of the response surface cross sections at the opening of the flow section of the seat for 1, 3 and 5 cm shows that with the increase of the working pressure per unit, regulator flow increases by an average of 94.59, 116.31 and 138.03 cm³/s respectively. Thus, changes in the investigated range of increment with the arguments changing with increasing values on regulator seat by opening the seat the pass through the controller, but at the same time the degree of influence of this factor increase.
Keywords: belt controller, the response function, level, operating pressure, water flow.
