In this study, a slightly curved Euler Bernoulli beam carrying a concentrated mass was handled. The beam was resting on an elastic foundation and simply supported at both ends. Effects of the concentrated mass on nonl...In this study, a slightly curved Euler Bernoulli beam carrying a concentrated mass was handled. The beam was resting on an elastic foundation and simply supported at both ends. Effects of the concentrated mass on nonlin- ear vibrations were investigated. Sinusoidal and parabolic type functions were used as curvature functions. Equations of motion have cubic nonlinearities because of elongations during vibrations. Damping and harmonic excitation terms were added to the equations of motion. Method of mul- tiple scales, a perturbation technique, was used for solving integro-differential equation analytically. Natural frequen- cies were calculated exactly for different mass ratios, mass locations, curvature functions, and linear elastic foundation coefficients. Amplitude-phase modulation equations were found by considering primary resonance case. Effects of nonlinear terms on natural frequencies were calculated. Frequency-amplitude and frequency-response graphs were plotted. Finally effects of concentrated mass and chosen curvature function on nonlinear vibrations were investigated.展开更多
In the process of separating the fiber from the seed, the density of the seed roll in the roll box of the saw gin is constantly changing. With an increase in the density of the seed roll, the quality indicators of fib...In the process of separating the fiber from the seed, the density of the seed roll in the roll box of the saw gin is constantly changing. With an increase in the density of the seed roll, the quality indicators of fiber and seed deteriorate, energy consumption increases, machine breakdowns increase, and with a decrease in density, the productivity of the machine decreases. For this reason, the regulation of the density of the seed roll is one of the important problems in the ginning process. For this, the speed of rotation of the feed rollers changes, which, with an increase in speed, the mass of cotton increases, and with a decrease, it decreases. Thus, the density of the seed roll is controlled. The article describes the problem of regulating the density of a seed roll in a saw gin of the DP series, an overview of the work on regulating the operation of the machine is given. In this work, the force of cotton pressure between two feed rollers is also theoretically investigated. Graphs of changes in the force of cotton pressure between two rollers are plotted depending on various initial pressure forces. The results of the study will be used in the further improvement of the cotton feeding regulation in order to maintain the optimum density of the seed roll, which will preserve the quality of the fiber and seeds while increasing the productivity of the machine.展开更多
文摘In this study, a slightly curved Euler Bernoulli beam carrying a concentrated mass was handled. The beam was resting on an elastic foundation and simply supported at both ends. Effects of the concentrated mass on nonlin- ear vibrations were investigated. Sinusoidal and parabolic type functions were used as curvature functions. Equations of motion have cubic nonlinearities because of elongations during vibrations. Damping and harmonic excitation terms were added to the equations of motion. Method of mul- tiple scales, a perturbation technique, was used for solving integro-differential equation analytically. Natural frequen- cies were calculated exactly for different mass ratios, mass locations, curvature functions, and linear elastic foundation coefficients. Amplitude-phase modulation equations were found by considering primary resonance case. Effects of nonlinear terms on natural frequencies were calculated. Frequency-amplitude and frequency-response graphs were plotted. Finally effects of concentrated mass and chosen curvature function on nonlinear vibrations were investigated.
文摘In the process of separating the fiber from the seed, the density of the seed roll in the roll box of the saw gin is constantly changing. With an increase in the density of the seed roll, the quality indicators of fiber and seed deteriorate, energy consumption increases, machine breakdowns increase, and with a decrease in density, the productivity of the machine decreases. For this reason, the regulation of the density of the seed roll is one of the important problems in the ginning process. For this, the speed of rotation of the feed rollers changes, which, with an increase in speed, the mass of cotton increases, and with a decrease, it decreases. Thus, the density of the seed roll is controlled. The article describes the problem of regulating the density of a seed roll in a saw gin of the DP series, an overview of the work on regulating the operation of the machine is given. In this work, the force of cotton pressure between two feed rollers is also theoretically investigated. Graphs of changes in the force of cotton pressure between two rollers are plotted depending on various initial pressure forces. The results of the study will be used in the further improvement of the cotton feeding regulation in order to maintain the optimum density of the seed roll, which will preserve the quality of the fiber and seeds while increasing the productivity of the machine.
