Застосування методів теорії планування експерименту для дослідження економічності пневмодвигуна

Abstract. Problem. In the article, using computer modeling in the MATLAB environment, a full factorial experiment was conducted to optimize the working process of a pneumatic engine, during which the influence of independent parameters (valve opening-closing angles) on its specific indicator air flow rate was evaluated. As a result of the experiment, the second-order regression equation was obtained and the most significant factors and their mutual combinations affecting the response parameter were determined. Goal. Conduct a full factorial experiment (FFE). Task: based on the analysis of the literature, taking into account various factors, select the plan for conducting the experiment. To construct graphical dependences of the influence of factors (angles of opening and closing of intake valves on the specific effective flow rate of compressed air in the pneumatic engine and to determine their influence on the indicator air flow rate. Methodology. The central composite rotatable plan of a different order proposed by Box and Behnken was used in the work. Previously, in order to reduce the number of experiments, the Plackett and Burman method was used to filter out insignificant factors. The factors varied on three levels. The subject of the study is the relationship between the specific indicator flow of compressed air and the opening-closing angles of the pneumatic engine valves. Results. It can be seen from the above relationships that the specific effective flow rate of compressed air g i increases with an increase in the closing of the intake valve (X2) and an increase in the closing of the exhaust valve (X4). Increasing or decreasing the opening angles of the intake (X1) and exhaust (X3) valves and the closing of the exhaust valve also leads to an increase in the specific effective flow rate of compressed air in the pneumatic engine. A multifactorial optimization of the operation of the pneumatic engine D / S = 9.2/9.2 was carried out. As a result of the analysis of the calculations, kW and kg/h were obtained. Originality. The proposed method of determining the extremum of the specific indicator flow rate of compressed air. This is achieved by conducting an extreme experiment to construct a multifactor response function followed by solving the unconditional optimization problem using the simplex method. Practical value. The dependence of the minimum specific indicator flow rate of compressed air on the angle of valve opening and closing is selected as parameters for assessing the technical level of pneumatic engine.