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The blast furnace permeability index is one of the crucial technical indicators in the ironmaking process of a blast furnace. Given that the conventional models are not entirely suitable for accommodating the intricate characteristics of blast furnace production, this paper explores a comprehensive approach that involves data mining, the sparrow search algorithm (SSA), convolutional neural networks (CNNs), and gated recurrent unit networks (GRUs) for predicting the blast furnace permeability index. Initially, to address the multi-noise nature of blast furnaces, outliers are eliminated, and a Kalman filter is devised for denoising purposes. Subsequently, in consideration of the nonlinear and substantial time-delay features of blast furnaces, the maximal information coefficient (MIC) method is employed for time-delay alignment, followed by the selection of model input variables based on process analysis and relevance. Subsequent to this, the SSA-CNN-GRU model is established. Within the modeling process, a one-dimensional convolutional neural network is utilized to extract distinct process variable features, thus further resolving the interdependence among blast furnace data. Ultimately, the effectiveness, accuracy, and advancement of the proposed method are validated using real production data. [ABSTRACT FROM AUTHOR]

This study performs a systematic analysis of the dynamic behavior of a crack rotor-bearing system with rub-impact effect. The dynamic orbits of the system are observed using bifurcation diagrams plotted using the dimensionless damping coefficient, the dimensionless unbalance parameter and the dimensionless rotational speed ratio as control parameters. The analysis methods employed in this study include the dynamic trajectories of the crack rotor-bearing system, power spectra, Poincaré maps and bifurcation diagrams. Lyapunov exponent and fractal dimensional analysis are also used to identify the onset of chaotic motion. The numerical results reveal that the system exhibits a diverse range of periodic, sub-harmonic, quasi-periodic and chaotic behaviors. The results presented in this study provide an understanding of the operating conditions under which undesirable dynamic motion takes place in a crack rotor-bearing system and therefore serve as a useful source of reference for engineers in designing and controlling such systems.

The pure squeeze magneto-elastohydrodynamic lubrication (MEHL) motion of circular contacts with an electrically conducting fluid in the presence of a transverse magnetic field is explored under constant load condition. The differences between classical elastohydrodynamic lubrication and MEHL are discussed. The results reveal that the effect of an externally applied magnetic field is equivalent to enhancing effective lubricant viscosity. Therefore, as the Hartmann number increases, the enhancing effect becomes more obvious. Furthermore, the transient pressure profiles, film shapes, normal squeeze velocities, and effective viscosity during the pure squeeze process under various operating conditions are discussed. [DOI: 10.1115/1.4002182] Keywords: magneto-elastohydrodynamic lubrication, squeeze-film, constant load

In this paper, an elastic sphere approaching a lubricated elastic coating surface with couple stress lubricant is explored under constant load condition. The finite difference method (FDM), Gaussian elimination, and Gauss-Seidel iteration method are used to solve the transient modified Reynolds equation with its boundary condition, the elasticity deformation equations of ball and coating layer, load balance equation, and lubricant rheology equations simultaneously. The transient pressure profiles, film shapes, and elastic deformation during the pure squeeze process under various operating conditions in the elastohydrodynamic lubrication (EHL) regime are discussed.

The generator is the most popular mobile power device and backup power device in the world. It is very important for human life. Therefore, it is important to develop more efficient combustion technology in order to save energy and reduce air pollution. In this paper, a novel technology of hydrogen and oxygen compound gasoline fuel is developed. Hydrogen and oxygen gases are produced from an electrolytic cell and then mixed with the intake gasoline and air. The compound fuel is sucked into the engine combustion chamber. The hydrogen and oxygen gases can be produced immediately without any storage device of hydrogen. The experimental results show that this technology can increase the power generation and decrease emission pollution due to promoting combustion efficiency. In addition, the spark plug seat temperature increases due to higher heat value of hydrogen. This technique can reduce carbon monoxide and HC, but increase carbon dioxide. The research and development of this technique can achieve the goals of energy saving, emission reduction, relative safety, easy refitting and low refitting expense. Moreover, this research possesses academic innovation and industrial application. [ABSTRACT FROM AUTHOR]

In this study, the nonlinear dynamic analysis of the hybrid squeeze film damper mounted on a gear-rotor-bearing system is presented. The strong nonlinear oil film force, nonlinear rub-impact force between the rotor and stator, and the gear meshing force are considered in this study. The bifurcation diagrams are plotted using a dimensionless imbalance factor, damping coefficient, and speed ratio as control parameters in this study. The beginning of chaotic motion is identified by phase diagrams, power spectrum, Poincaré maps, bifurcation diagrams, maximum Lyapunov exponent, and the fractal dimension of the system. The numerical results provide useful insights into the design and development of a gear-rotor-bearing system for rotating machinery that operates at high speeds and highly nonlinear conditions. Hybrid squeeze film damper is used to suppress irregular dynamic behaviors and reduce greater amplitude, even if the rotational speed of the rotating machine is higher, which is also confirmed in this study. [ABSTRACT FROM AUTHOR]