A New Method for Calculating the Cementation Exponent of Triple-Porosity Media Reservoirs

The value of a cementation exponent, usually obtained by rock and electricity experiments, significantly affects the calculation of water saturation, thickness of the hydrocarbon reservoir, and recovery rate. The determination of the cementation exponent for porous-media reservoirs has been a challenge because of the limited core sampling. A new method was proposed to determine the value of cementation exponent for complex triple-porosity media reservoirs in the work. Firstly, the work discussed the effects of fractures and nonconnected vugs on the cementation exponent of the reservoir as well as the calculation method of the cementation exponent of the dual-porosity media reservoir. Then, a new model for calculating the cementation exponent of triple-porosity media reservoirs was derived by combining the Maxwell-Garnett theory and series-parallel theory, which matched with the real physical-experiment data of rocks. The results showed that the fractures decreased the cementation exponent of the reservoir but the vugs increased. The mixture of matrix pores, fractures, and vugs made the value of the cementation exponent of the triple-porosity media reservoir vary around 2.0. The conductivity of the triple-porosity media reservoir was the external macroscopic expression of the microscopic conductive network. The new calculation model of the cementation exponent proposed in the work could reasonably predict the cementation exponent of the strongly inhomogeneous triple-porosity media reservoir.

STRESS-DEFORMED STATE OF THE FOUNDATION OF HYDRAULIC STRUCTURES AT CONTROLLED COMPENSATION DISCHARGE

Nnumerical simulation of the process of injection of mortar into the thickness of the sandy base during the work on lifting and leveling the structure by the method of compensatory injection is carried out. An author's program has been developed that implements the finite element method (FEM) in a spatial formulation, taking into account the elastic-plastic nature of soil deformation, in which a special element in the form of a spheroid has been developed to describe the expanding area at the location of the injector, which changes its volume during the injection of mortar. During the verification of the program, the results of mathematical modeling were compared with the data of a physical experiment conducted by PhD Luca Masini from the University of La Sapienza (Rome, Italy). Numerical modeling of the stress-strain state of the base of the structure during repair work is considered by the example of lifting the foundation plate of the Zagorskaya PSPP-2. A number of tasks are being solved related to minimizing the number of injection columns, their location, the pitch of the cuffs, the selection of portions of the injected solution, taking into account the requirements for uniform lifting of the foundation plate in order to avoid additional cracking.

Scheme Design and Data Analysis of Critical Physical Experiment for Hexagonal Casing Type Fuel Reactor

Based on the requirement of Hexagonal Casing Type Fuel Reactor (HCTFR) nuclear design and the critical physical experiment design method introduced by a single factor, 11 core critical physical experiments are proposed to validate the calculation accuracy and reliability of the nuclear design code CPLEV2. The experiment loading scheme fully takes into account the various components and more than one irradiate hole in the HCTFR core, which is used as critical physical experiment schemes successfully. According to the critical physical experiment data, the reactivity calculation deviations of all critical physical experiments are within ±1.0%. The validation results show that the nuclear design code CPLEV2 has high calculation accuracy and reliability for the core of hexagonal casing type fuel, and it can be used for HCTFR nuclear design.

DIY electrodynamic trap for physics education

We present a simple and affordable method for making a surface electrodynamic trap for microparticles. The principles of electrodynamic trapping of charged particles are discussed and step-by-step instructions on how to make a surface trap are given. In addition to the electrodynamic trap implementation and operation process, options for its further use are proposed. The work may be of interest to physics teachers as a material for practical work, for the formation of students’ skills in performing a physical experiment.

Program Complex for Automated Calculation of the Geometry of Impact Units of Machines

Improving the designs of impact mining machines in order to increase the productivity of drilling operations requires calculations of the geometric parameters of impact units. The greatest effect when the impact is applied to the rock is given by an impact pulse corresponding to the resistance forces of the object being destroyed. In turn, the shape and parameters of the impact pulse are determined by the geometry of the colliding bodies. Analytical methods for analyzing dynamic processes in impact systems involve the use of a very complex mathematical apparatus, which does not allow us to quickly solve the problems of engineering design of machines and mechanisms. The authors of this article have developed a numerical method for calculating and analyzing impact pulses generated in the machine system by bodies of any geometric complexity. The reliability of the theoretical approaches is confirmed by the results of a physical experiment. The developed software allows you to quickly and accurately solve the problem of finding and justifying rational geometric parameters of impact nodes of machines.

Hydrogeology Response to the Coordinated Mining of Coal and Uranium: A Transparent Physical Experiment

The migration of fracture and leaching solute caused by mining activity is critical to the hydrogeology. To characterize liquid and solid migration in a mining area of intergrown resources, the coordinated mining of coal and uranium was considered, and a physical experiment based on transparent soil was conducted. A well experimental performance of transparent soil composed of paraffin oil, n-tridecane, and silica gel and the leaching solution comprised of saturated oil red O dye was observed for hydrogeology characterization. An “arch-shaped” fracture zone with a maximum height of 90 m above the mined goaf and a “horizontal-shaped” fracture zone with a fractured depth of 9.97–16.09 m in the uranium-bearing layer were observed. The vertical leachate infiltration of 4.83 m was observed in the scenario of uranium mining prior to coal, which is smaller than those in the scenarios of comining of coal and uranium (10.26 m) and coal mining prior to uranium (16.09 m). A slight strata movement below the uranium was observed, and the leaching solution infiltration in the coal mining area was not observed in a short period in the scenario of uranium mining prior to coal; both of those was presented in the scenarios of comining of coal and uranium and coal mining prior to uranium.

Investigation of the interference pattern from a spherical particle at different viewing angles

The work aim is to investigate the influence of the parameters of the laser interference method experimental setup on the obtained images. Using computer modeling based on the diffraction theory and physical experiment, the change in the parameters of the interference pattern for different viewing angles had been shown. The results can be used to develop a single algorithm for processing images of the laser interference method.

FORMATION OF PRACTICAL SKILLS IN STUDENTS WITH THE HELP OF EXPERIMENTAL PROBLEMS IN PHYSICS

The article introduces one of the ways to form students' practical skills by solving experimental problems focused on a specific practical method that can be successfully used to solve life's cognitive problems. The introduction of the proposed approach was preceded by the study of the opinions of physics teachers of secondary schools in the Volyn region of Ukraine. The attitude and wishes of students from the same region to solving experimental problems are clarified. The definition of experimental problems is offered as follows: these are the problems with the data taken from the experiment to obtain a solution. The solution of experimental problems is considered as a part of educational physical experiment, which is an essential component of the methodical system of teaching physics, as it provides the formation of the necessary practical and research skills. A series of experimental problems that provide the formation of practical skills of students on the example of educational material devoted to the study of the concept of "density of matter". A solution is proposed for each problem. The views of scientists on the problem of using experimental problems in the practice of physics lessons are reflected; the difficulties that teachers face when using the mentioned type of tasks are outlined. A study of corresponding textbooks in recent years on the problem of using experimental problems in the practice of teaching students is conducted. Methodical recommendations on the choice of time for solving the given series of experimental problems, forms of work of students in a modern physics lesson are offered. Attention is paid to the selection and solution of experimental problems of other educational material related to the concept of "density of matter", the place and forms of their solution in the practice of the lesson are substantiated. The effectiveness of the proposed approach to solving experimental problems on the basis of expert evaluation is established.