Dynamics of pneumatic drive of devices for udder massage of animals

The paper presents the results of theoretical developments on the deformation of flexible shells of the executive bodies of the means of stripping, the assessment of their mechanical impact on the udder of the heifer and first-calf, the dynamics of the pneumatic drive of the executive bodies. The design and technological parameters of the devices for milking first-calf heifers and massaging the udder of heifers are justified, the set and duration of technological operations for animal milking and the economic efficiency of their implementation are determined.

Flow control method by applying flexible shells procedure in transonic flow

Purpose In the present research, the effect of the flexible shells method in unsteady viscous flow around airfoil has been studied. In the presented algorithm, due to the interaction of the aerodynamic forces and the structural stiffness (fluid-structural interaction), a geometrical deformation as the bump is created in the area where the shock occurs. This bump causes instead of compressive waves, a series of expansion waves that produce less drag and also improve the aerodynamic performance to be formed. The purpose of this paper is to reduce wave drag throughout the flight range. By using this method, we can be more effective than recent methods throughout the flight because if there is a shock, a bump will form in that area, and if the shock does not occur, the shape of the airfoil will not change. Design/methodology/approach In this simulation pressure-based procedure to solve the Navier-Stokes equation with collocated finite volume formulation has been developed. For this purpose, a high-resolution scheme for fluid and structure simulation in transonic flows with an arbitrary Lagrangian-Eulerian method is considered. To simulate Navier-Stokes equations large eddy simulation model for compressible flow is used. Findings A new concept has been defined to reduce the transonic flow drag. To reduce drag force and increase the performance of airfoil in transonic flow, the shell can be considered flexible in the area of shock on the airfoil surface. This method refers to the use of smart materials in the aircraft wing shell. Originality/value The value of the paper is to develop a new approach to improve the aerodynamic performance and reduce drag force and the efficiency of the method throughout the flight. It is noticeable that the new algorithm can detect the shock region automatically; this point was disregarded in the previous studies. It is hoped that this research will open a door to significantly enhance transonic airfoil performance.

ALGORITHMIZATION OF SOLVING DYNAMIC EDGE PROBLEMS OF THE THEORY OF FLEXIBLE RECTANGULAR PLATES

In this paper, a computational algorithm is developed on the basis of the finite difference method for solving dynamic edge problems of the theory of flexible shells with account for shears and rotary inertia. Dynamic calculations of flexible plates is used in designing hulls of ships, aircraft, missiles, and other technical objects, which, along with sufficient strength, should have the least weight ensured by the use of lightweight plates and by reducing the margin of safety. The problem of developing an automated system for solving problems of the theory of elasticity and plasticity was first raised in the monograph by V.K. Kabulov. This work reveals the main problems of algorithmization and indicates approaches for their machine solution. In accordance with the analyzed problems, which arise during automated calculations of thinwalled elements of mechanical engineering structures, it is reasonable to use a nonlinear dynamic computational scheme for a flexible homogeneous isotropic linear elastic shell of arbitrary shape and to take into account the effect of both shears and rotary inertia when describing the motion of the shell. Such a model allows one to apply a sufficiently flexible and fast-acting scheme to calculate a wide class of dynamic processes taking place within the plates and shells of different shapes which are not over-limited in thickness and serve as significant parts of mechanical engineering elements. A number of dynamic differential equations of plate motion have been developed and tested. Obviously, there is no need to build other algorithms to calculate flat plates when developing an automated computational system.