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In the northern Tarim Basin, a large number of thick igneous rocks are encountered in the drilling process in the Permian. Their lithology and velocity are very strongly, which has a great influence on migration imaging of the “beaded” areas. It is very important to conduct the fine lithology identification and high-precision velocity modeling of the igneous rocks for the exploration and development of the reservoirs. A geostatistical inversion method to obtain the igneous-rock lithologic distribution pattern and velocity modeling in the FY area of the northern Tarim Basin is introduced in this paper. The results show that the application of the geostatistical inversion method greatly improves the resolution of lithology identification. This helps us further understand the Permian igneous rocks distribution in the FY area. Comparison between the seismic facies classification maps of the FY study area shows that the obtained velocity model can reflect the lateral distribution of igneous rocks well. At the same time, the velocity model can reflect the variation of igneous rocks velocity in detail and has a high precision. The average velocity error of the wells participating in the inversion is less than 2%, and the minimum average velocity error is 0.23%. Finally, the velocity model is applied to seismic data processing, and the processing results indicate that it can help to improve seismic migration imaging. The study demonstrates that the geostatistical inversion method can provide a high-precision velocity model for formation pressure prediction and seismic data processing and interpretation, ultimately guiding the exploration and development of oil.

The hydrocarbon formation mechanism and potential targets in clastic strata from the Tabei Uplift, Tarim Basin, are documented using the fault mesh petroleum plays theory, based on integrating seismic, well log, well core and geochemistry data. The reservoirs in the Donghetang area are typical allochthonous and far source fault mesh petroleum plays. There are two sets of fault meshes in the study area: (1) the Donghe sandstone and combination of Permian and Triassic strata and (2) combination of the J_IV and J_III formations in the Jurassic strata. The fault mesh petroleum play in the Jurassic is a secondary reservoir that originates from the Carboniferous Donghe sandstone reservoir adjustment based on source correlation. The fault mesh carrier systems are divided into four styles according to the fault mesh architecture: (1) fully connected, (2) fault-unconformity-transient storage relay, (3) fault-transient storage-unconformity relay, and (4) transient storage-fault relay. According to the characteristics of the fault mesh petroleum plays, the reservoirs are of 15 types and form three categories: upper transient storage, inner transient storage, and margin-transient storage. Integrated analysis of the hydrocarbon generation and faulting time periods reveals that there were four periods of hydrocarbon charging, with the first three stages charging the reservoirs with oil and the last stage charging the reservoirs with gas. There are multiple stages of reservoir accumulation and adjustment in the fault mesh in the study area. These multiple stages of fault mesh accumulation and adjustment are the main reason that the multiple vertical units of the reservoirs have different hydrocarbon properties. Fault-block reservoirs and lithologic reservoirs related to the inner transient storage and upper transient storage styles are the main exploration targets in the clastic strata in the study area.

The effect of the Reynolds number on the mechanism of formation of an instantaneous local flow separation that occurs in the near-wall region of a turbulent boundary layer is experimentally studied. The features of application of the high-speed planar PIV method with a high spatiotemporal resolution are discussed. Comparison of the measurement results obtained within a viscous sublayer of a turbulent boundary layer with the results of other studies showed the generality of the mechanism for the formation of an instantaneous local flow separation in the range of dynamic Reynolds number 207 ≤ Re _τ ≤ 672.

A three-dimensional turbulent round jet impinging on a heated flat plate is investigated numerically. The effects of the nozzle geometry and nozzle-to-plate distance on the dynamical and thermal behavior are explored. A round nozzle and nozzles fitted with either 4 or 6 chevrons are considered. Three nozzle-to-plate distances are studied: H/D = = 2, 4, and 6. The Reynolds number equals 5000. The results show that the chevrons improve the heat transfer near the area of stagnation. This improvement can reach up to 110 % in specific regions. It is also found that the wall heat flux is appreciably non-uniform for the small distance H/D = 2. Degraded heat transfer is recorded between the plate and the fluid in narrow radial passages of fluid downstream of the stagnation point for the small value of H/D. They turn out to be quasi-potential flow streams, along the target wall and facing the chevron apices, characterized by high convective velocities and nearly no turbulence. Increasing the distance to H/D = 6 yields a somewhat axisymmetric thermal behavior. Effects on Nusselt number values averaged over circular surfaces centered on the stagnation point and of variable radius on the target wall are highlighted.

Results of an experimental study of the kinematic structure of flow and the transfer of heat in gradient flows are reported. A field measurement method (SIV) was used to obtain profiles of velocities and turbulence characteristics in characteristic sections of diffuser and confuser channels. Based on the results of thermal measurements, the distributions of the heat-transfer coefficient on the wall of a flat diffuser/confuser were obtained in a wide range of regime parameters. The mechanisms of the formation of the transfer of heat in gradient flows are analyzed. It is shown that, in a diffuser channel, the transfer of heat on the wall as a whole depends on the flow parameters at the diffuser inlet. For a confuser channel, this relation can be determined using the local values of longitudinal flow velocity.

The wetting dynamics of modified capillary-porous surfaces made of aluminum and titanium was experimentally studied at free-convective heat exchange with the environment. The influence of the concentration of ethyl alcohol and its initial temperature on the wetting front velocity has been established. The volume concentration of alcohol in the mixture varied from 0 to 95.5%. The characteristic modes of changes in the height of the liquid rise over capillary-porous surfaces over time have been expressed in the form of power dependences.

The two-phase flow was experimentally studied in three horizontal channels of rectangular cross-section: 0.23×1 mm, 0.51×1 mm, and 1×1 mm. Distilled water was used as a liquid, and nitrogen was used as a gas. The paper considers in detail the features of two-phase flow formation. The effect of the rectangular channel height on the boundaries of two-phase flow regimes was investigated. It was found that the region of the bubble flow is hardly affected by the channel height; however, with a decrease in the latter, the region of the slug flow decreases significantly, while the region of the slug-annular flow expands. The characteristics of the slug flow have been studied in detail. The dependences of the length of gas slugs and liquid bridges on the reduced liquid velocity, the reduced gas velocity, and also the channel height have been studied. A comparison with known correlations is made and it is shown that they describe the experimental data in a narrow range of parameters, and as the height of the rectangular channel decreases, the data scatter increases.

The large-eddy simulation method was applied to study of isothermal swirled gas flow in a model combustion chamber at Reynolds number Re = 15000. The study identified a coherent vortex structure: this is a precessing vortex core which contributes to pressure pulsations reaching a maximum inside a model front device. It is possible to suppress this coherent structure by gas injection in a site of highest pressure pulsations. The study covers three regimes with additional gas injection with the amplitude about 1 - 5 % of the superficial flow velocity. Analysis of instant, average and spectral characteristics revealed that the developed method of flow control is a tool for suppression of low-frequency oscillation by factor of two.

Mathematical simulation was applied to flame spreading and the flame front speed through the air suspension of boron particles as a function of pressure, excess oxidant ration and the particle size. Simulation accounts for a change in heat and mass transfer with a reduction of the particle size from micro-size to nano-scale. The model of flame front propagation through boron particle suspension in air (with account for molecular-kinetic mechanism of heat and mass transfer) allows analysis of the normal speed of flame propagation as a function of initial size of boron particles, oxidant excess ratio and pressure. The conditions were estimated and existence of extremes and flat zones was justified due to a change in heat and mass transfer regime change in a continuous medium while transition to the free-molecular flow regime.

The experimental results obtained by the dilatometric method for thermal expansion of the Hastelloy C276 alloy in the temperature range of 100 - 370 K are presented. Temperature dependences of thermal properties have been obtained. The obtained results have been compared with the data for thermal expansion of superconducting tapes of the “Amperium” and “SuperOx” brands Keywords: