Experimental Study of Pore Permeability Characteristics Based On Variable-Mass System In Karst Collapse Pillars

Particle loss is the root cause for the occurrence of Karst Collapse Pillars (KCP) sudden water events. The pore adjustment of KCP filler will further induce seepage destabilization, and it is also a process that sudden water catastrophe must go through. In order to investigate the direct relationship between stress conditions, water pressure conditions, and gradation structure on the pore structure of rock samples, the steady-state percolation method was used to investigate the percolation test system of variable-mass crushed rock masses. The results show that: 1) the structural characteristics of rock grains under the same stress environment are closely related to their extrusion fragmentation process and the softening and scouring effect of water. Rubbing, rotating, fracturing, grinding and plugging are the main forms of action of their intergranular action. 2) The filling particles before and after the loss meet the fractal law and have fractal characteristics. 3) The percentage of fine particles in the whole process of infiltration loss is as high as 34.4%. The adjustment of pore structure is related to the particle size gradation, and the reciprocal action of water flow will form a stable water-conducting channel. 4) The sudden water process of the specimen under particle loss can be divided into three stages: initial seepage, catastrophic destabilization and pipe flow surge.

Installation for studying the parameters of localiInstallation for studying the parameters of localization of an electromagnetic wave in a waveguide of variable cross-section in the framework of the predictions of the 5-D extended space modelzation of an electromagnetic wave in a waveguide of variable cross-section in the framework of the predictions of the 5-D extended space model

The paper describes the creation and testing of an experimental setup for studying the parameters of localization of electromagnetic microwave radiation with a power of 0.001-0.004 W in the range of 36.0-79.0 GHz when propagating radiation in metal waveguides of variable cross-section. Measurements will also be carried out under conditions of filling the waveguide with dielectric materials with refractive indices from 1.46 to 4.0 for microwave radiation of the specified range. The installation is designed to measure the parameters of the localization of microwave radiation when it passes through a waveguide of variable cross-section, filled with materials with different refractive indices. Interpretation of the results will be carried out within the framework of the 5-D extended space model (ESM). The extended space model is formulated in (1+4)-dimensional space time-coordinate-interval. An additional spatial coordinate in the ESM is the interval. In the conjugate 5-D space, the energy-momentum-mass interval in the ESM corresponds to mass. In the ESM formalism, the question of the appearance of a nonzero variable mass in a photon and its localization under the influence of an external field is studied.

The Role of Nonlinear Body Force in Electrostatic Propeller Driven by Atmospheric DC Corona Discharges

In this study, the body force generated by atmospheric positive and negative corona discharges were investigated using a wire-cylinder configuration experimentally and numerically. We provided new insight into the atmospheric electric thruster by introducing a nonlinear term in body force constituent the thrust of the system. It was observed that the direction of both body forces and electric winds is always from the wire to the cylinder irrespective of the applied voltage polarity. It was illustrated that the corresponding thrusts and the electric wind of the positive corona are larger than that of the negative corona discharge. We took into account the nonlinear mechanisms to explain the difference in thrust forces in positive and negative corona discharges. To elucidate the origin of the body force in corona discharges, we performed 2-D simulations via COMSOL Multiphysics and MATLAB software. The results of the numerical simulation showed that in addition to the linear body force (Coulomb force) a strong nonlinear body force is generated around the wire electrode that plays a crucial role in corona thrusters. To verify the direction and magnitude of the thrust, a simple theory was proposed based on variable mass systems and confirmed by published experimental works.