AN ENGINEERING APPROACH TO THE STUDY OF THE PROCESSES OF DOUGH FLOW IN THE PRODUCTION OF PASTA AT AGRO-INDUSTRIAL ENTERPRISES

Abstract

Background. In modern conditions, the provision of domestic pasta produced from durum wheat varieties on modern technological equipment is becoming important. At the same time, the quality of the finished pasta is also determined by the rheological properties of the pasta dough when passing through the pasta press matrix, which determined the purpose of the study to develop a method of computational evaluation for calculating the relationship between the speed parameters of the flow of pasta dough in the cylindrical sections of the channels of the molding matrix with pressure drops to overcome viscous resistance, the dimensions of the structural elements of the channel, as well as with indicators of the rheological properties of pasta dough. Materials and methods. To study the flow of pasta dough, baking flour of the highest grade M-54 28 was chosen as a raw material in stepped cylindrical channels. The applied rheological model is described and a technique for mathematical modeling of the flow parameters of pasta dough in cylindrical channels is given. Due to the small contribution of the pasta dough shear strength to the total pressure loss, a rheological model of a nonlinear-viscous medium is used, which is described by a power equation containing physically determined constants. Neglecting the elastic deformations of the dough due to their smallness, we assumed the condition of constancy of the volumetric productivity for each cross section of the channel. Results. Analytical dependencies are presented that relate the change in velocity over the channel cross section to the pressure developed necessary to overcome the viscous resistance, as well as to the radii and length of the channel, and to the rheological properties of the pasta dough. These dependences formed the theoretical basis of the method for calculating the parameters of pasta dough flow in cylindrical channels. Conclusion. On the example of an industrial matrix of a pasta press, made in the form of a system of cylindrical channels of a stepped-variable diameter in the preforming zone, calculations were made to determine the average and maximum flow rates of pasta dough in each section of the channel and the developed pressure. The results of the research can be used in engineering practice when designing new matrices for forming pasta dough and in the production processes of enterprises to calculate their production capacities.