Study of non-steady process in “Single-acting piston pump – damless pitched-blade hydroturbine” hydrodynamic system

Abstract

This research is concerned with the study of the interaction of single-acting crank pump with the damless pitch-blade hydroturbine exciting its vibrations with the limited power. With this view we develop a new mathematical model describing the process of interaction of single-acting crank pump with the damless pitch-blade hydroturbine. Connexity of processes occurring in the single-acting crank pump and in the source of energy – in the hydroturbine leads to the qualitatively new effects in their dynamics which cannot be detected through examining the problem in formulation of the ideal excitation. A new model of the motion effect of the single-acting crank pump to the power source – damless hydroturbine is developed and studied. The special attention is paid to the study of effect of parameters of the single-acting crank pump to the hydroturbine motion modes. It was established that the system motion equation is essentially nonlinear and has a large nonlinearity parameter in the first-order derivative, the hydroturbine rotates unevenly and the coefficient of irregularity of rotation of the hydroturbine depends on the parameters of the crank-piston pump and hydroturbine. The values of the hydroturbine angular speed at the no-load operation correspond to its maximum values. The minimum values of the angular speed depend on the parameters of the hydroturbine and piston pump, and the maximum values of the angular speed depend only on the hydroturbine parameters. The results of the research can be used in designing of the new crank-piston pumps. DOI: http://dx.doi.org/10.5755/j01.mech.21.4.10163