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Актуальность. Отклонение от проектной траектории скважин приводит к ошибочным результатам и как следствие к невыполнению поставленной задачи бурения. К важным геологическим условиям, которые влияют на искривление скважины, относятся сланцеватость, трещиноватость, слоистость, перемежаемость слоев пород различной твердости, флюидальность, пористость, зоны дробления пород, разломы, пустоты, твердые включения и т. п. Как показывает опыт проведения буровых работ, значительная часть перебуриваемых горных пород являются анизотропными. Показатель анизотропии горных пород характеризует степень совокупного влияния нескольких факторов на процесс естественного искривления скважин. Тип инструмента и параметры режима бурения являются основными факторами такого рода. Борьба с естественным искривлением зачастую вызывает технические затруднения и связано с большими затратами времени и материальных ресурсов. В связи с этим актуальным является изучение особенностей бурения в условиях анизотропии горных пород и рассмотрение возможностей влияния на искривление скважин при повышенной флюидальности. Цель: определение возможностей влияния на естественное искривление скважин при бурении в анизотропных горных породах. Объект: механизм разрушения анизотропной горной породы. Методы: экспериментальные, аналитические исследования, анализ. Результаты. Применение в процессе бурения скважин жидкостей с добавлением поверхностно-активного вещества и гидродинамическое воздействие на забой способствуют снижению естественного искривления скважин. Активное воздействие очистного агента, содержащего поверхностно-активные вещества, на зону предразрушения породы устраняет неравномерность поражения забоя при движении резцов инструмента в направлении навстречу и вслед плоскостям флюидальности. Промывочный агент с добавками поверхностно-активного вещества снижает значение отношения скорости фрезерования породы в стенке скважины к углублению забоя, при этом особый эффект наблюдается при высокой механической скорости бурения скважины. Данное обстоятельство связано с возможностью проникновения промывочного агента в трещины, образовавшиеся в зоне предразрушения горной породы. Relevance. Deviation from the design trajectory of wells leads to failure to fulfill the drilling task. The main geological conditions affecting the curvature of the well include stratification, shale, fluidity, fracturing, porosity, intermittency of rock layers of different hardness, crushing zones, faults, voids, and solid inclusions. A significant part of the rocks drilled are anisotropic. The rock anisotropy index for drillability characterizes the degree of influence of the sum of factors on the natural curvature of wells. These factors primarily include the type of tool and the parameters of the drilling mode. The struggle with natural curvature often causes technical difficulties and is associated with a large investment of time. In this regard, it is relevant to study the features of drilling under conditions of rock anisotropy and to consider the possibilities of influencing the curvature of wells with increased fluidity. The aim of the research is to determine the possible effect on the natural curvature of wells when drilling in anisotropic rocks. Object: anisotropic rock destruction mechanism. Methods: experiment, analytical studies, analysis. Results. The decrease in anisotropy during drilling is actively influenced by flushing fluid with a surfactant on the rock prefracture zone. Such an effect tends to eliminate the unevenness of the face damage when the tool cutters move towards and after the fluidity planes, which is explained by a more intensive decrease in the strength characteristics of anisotropic rock precisely in the direction along the fluidity planes. The use of a flushing agent with the addition of a surfactant makes it possible to reduce the ratio of the rate of milling the rock in the wall of the well and the deepening of the bottom in combination with a high mechanical drilling speed under certain conditions. This circumstance is associated with the possibility of active penetration into the cracks of the prefracture zone of the washing agent with a surfactant.

Chemical water parameters in the Partizanskaya River estuary were measured on July 18–19, 2012 in conditions of low water discharge (20.1 m3 /s). In these conditions, the cline of salt water at the bottom penetrated up to 11 km upstream from the river mouth and the fresh river water passed the estuarine zone of mixing in approximately 2 days. Salt composition of the mixed water in the estuary had conservative dependence on salinity. By dynamical signs, the estuary could be divided into two zones: i) zone of active exchange between the surface freshwater layer and the bottom salted layer on the distance 5.5 km from the river mouth to the first sandy riverbank that the fresh river water passed in 12 hours, and ii) the upper part of the estuary with limited water exchange. The complex of water environments in the estuary, as good water transparency, strong stratification, and high concentrations of terrestrial nutrients, was favorable for phytoplankton blooming, so the chlorophyll concentration in the estuarine waters exceeded 40 μg/L. Destruction of autochthonous organic matter caused anomalies in distribution of carbonate and nutrient parameters and was accompanied by hypoxia in the bottom layer with the dissolved oxygen content lowering to 61 μM/kg.

Magnetic fluid is a colloid of magnetic nanoparticles. Using of magnetic fluids in technical devices demands applying of strong non-uniform magnetic fields for a long time. One of the most widespread magnetic fluid devices are magnetic fluid seals of mobile shafts, magnetic fluid supports, bearings, acceleration and angle of inclination gauges, devices for information input in the computer and etc. These devices demand high quality of used fluids. Processes of magnetophoresis and Brownian diffusion in magnetic fluid lead to concentration of magnetic particles in the areas with higher intensity of magnetic field and increase of fluid magnetization in these areas. A local change of particles concentration in the fluid leads to variation of its physical properties. Formation of aggregates from the particles and the further stratification of magnetic fluid, up to its destruction, may be the most serious consequence of redistribution of concentration of magnetic particles. These factors lead to variation of parameters of magnetic fluid devices; cause disturbance of their normal operation and even failure. Therefore, the consistent, high quality magnetic fluids which are not subject to fast stratification in a non-uniform magnetic field are necessary for effective work of the devices. The procedure of evaluation test of quality of magnetic fluids is proposed in this paper. The test is based on studying of influence of processes of magnetophoresis and Brownian diffusion of magnetic particles in magnetic fluid on the forces acting on the volume of fluid in an external non-uniform magnetic field. The procedure is developed on the basis of analysis of magnetic force variation in time under the action of non-uniform field of permanent magnets. Methods of determination of stability of magnetic fluid, known at present, demand rather complicated equipment and laborious and complex investigations. Proposed procedure can be used as an express method for evaluation of magnetic fluid quality for usage in technical devices, and it does not need complicated equipment.

Разработан гидродинамический метод расчета селективного водозаборного процесса в водоеме с непрерывной по всей глубине плотностной стратификацией. В качестве математической модели водозаборного процесса использована краевая задача линейной теории поверхностных гравитационных волн малой амплитуды в идеальной несжимаемой и неоднородной жидкости. Получена совокупность расчетных формул, которая позволяет решить задачу водоснабжения промышленных предприятий, в том числе тепловых и атомных электростанций, из водоемов с непрерывной плотностной стратификацией. Предлагаемый метод расчета позволяет определить скорость водозабора через окно и высоту водозаборного окна, которые обеспечивают надлежащее положение поверхности раздела, соответствующее заданной плотности (температуры) забираемой воды., The purpose of this work is to develop the hydrodynamic calculation method for selective water-intake process applied to the problem of water supply to industrial enterprises, including thermal and atomic power stations using the reservoirs with the continuous density stratification. In the method of solving the problem, the variation of density along the depth is approximated by an exponential function. The water is taken through a window arranged on the side of the water body. The boundary value problem for the linear theory of surface gravity waves of small amplitude in an ideal incompressible and inhomogeneous fluid is used as a mathematical model of the water intake process. As a result, a set of calculation formulas has been obtained that allows solving the problem of water supply to industrial enterprises, including thermal and nuclear power stations, from water bodies with a continuous density stratification along the depth. Computational experiments have been performed, the results of which are given in the form of graphs of the dependence of the thickness of the bottom layer of water sucking the window on the density Froude number and on the height of the water intake window. The following conclusions are made on the basis of the comparison of the developed hydrodynamic calculation method compared with the existing hydraulic method: 1. In the existing hydraulic method of calculation, only the law of the dependence of the thickness of the suction ground layer of water on the density Froude number is described, however the nature of its dependence on the height of the water intake window is not established. 2. In the hydrodynamic calculation method of selective water-intake process developed in the article, the law of the dependence of the sucking through the window water ground layer thickness both on the density Froude number and on the height of waterintake window is established. 3. In connection with the aforementioned deficiency of the hydraulic calculation method, in reservoirs characterized by a continuous density stratification in depth, calculations and design of selective water intake devices should be carried out according to the hydrodynamic method developed in the article., №1(23) (2018)

Retrospective analysis of airplane sounding of vertical component of electric field strength of atmosphere displayed four multiplet groups of peaks up to the height of 7 km. Seasonal mode stability of density of volume charge ∂E z /∂z equal to 20—24 complete vibrations of the field E z has been revealed. Correlative relation of statistical diagrams of the heights of cloudy horizons formation with equilibrium points of Helmholtz tensor components T zz has been found. Correlation coefficient r was 0,94÷0,98. Analogous correlations have been obtained according to the data of pilot­balloon observations for the vertical profiles of moisture distribution. For subsystems in strong internal fields (clouds) analytical analogue of Poisson sh­equation for self­consistent field of aerosol has been given. Results of calculations demonstrated that heavy charges of aerosol and impeded movement of Browne particles concentrate water steam in the vicinity of libration points of equilibrium — ionic planes.