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The performance of the grinding system is affected by the performance of the separator. It is significant to study the efficiency of the milling system for reducing the energy consumption of the whole grinding system. By changing the baffle plate parameters, the Distribution Law of the flow field inside the separator was analyzed, and the most reasonable structure parameters of the separator were obtained. By using the gas-solid two-phase model and the DPM discrete phase model, the classification efficiency and the total efficiency of the separator are calculated. It is verified that the parameters of the baffle plate are important factors to improve the efficiency of powder separation.

The interlayer plays an important role in the distribution law of remaining oil in the process of oilfield development, and it is of great significance to the later study of remaining oil distribution and the adjustment of oilfield development plans. Synthesize logging data, seismic data, and layering data of T5 oilfield, adopt the interlayer as the structural unit to build 3D model of the interlayer, which effectively reveals the distribution law of the interlayer. On the basis of this model, the facies-controlled modeling technology is used to build the attribute model, and lays a solid foundation for subsequent reservoir research work.

In view of the large deformation in the roadway of layered surrounding rock, with W22602 return air roadway of Datong No.1 Mine as the engineering background, using the finite-difference software FLAC3D, we explored the influence of the angle of the bedding plane under the prestressed bolt support on the plastic zone and the stress and strain distribution law of the surrounding rock of the roadway, and analyzed the deformation and failure characteristics of the bedding plane under the action of the bolt. The results show that: with the increase of the inclination of the bedding plane, the horizontal and vertical deformation of the bedding plane first increase and then decrease, showing a “Λ”-shaped change characteristic; in horizontal layered surrounding rock, as the prestress of bolt support increases, the strength of the weak rock layer gradually increases, and the surface displacement of the bedding plane gradually decreases; the plastic zone of the surrounding rock with different dip angles has a significant “angle effect”, and the angle between the bolt and the bedding surface has a significant difference in the control effect of the bedding plane; based on the simulation results when the inclination angle is 15°, field practice is carried out. And it shows that the optimization scheme can improve the stability of the surrounding rock of the roadway more economically and effectively.

T66 block of Aogula Oilfield is a block structure area, in which faults are relatively developed, with different oil-water systems in different fault blocks, obvious oil-water interbedding phenomenon in longitudinal direction, no unified oil-water interface and complex oil-water distribution. In order to solve this problem, the oil-water layer identification and oil-water distribution law of reservoirs in this area are studied by using drilling data and resistivity correction model, and the oil-water interpretation chart is established. The analysis shows that the whole area is controlled by fault-structure, and the oil-water difference between the two sides of the fault is large, which is obviously blocked by the fault, and the fault cutting controls the oil-water distribution Local fault blocks are controlled by structure-lithology, and the whole reservoir of high fault blocks is well developed, showing the characteristics of high oil and low water, while the reservoir of low fault blocks is discontinuous, showing the characteristics of lithologic upward dip and pinchout and lens controlling oil and water.

The determination of the structural type and location of the cofferdam is the key to the design, and the stability of the cofferdam is the premise to ensure the subsequent construction. Based on the actual project, the stability of the existing cofferdam during the foundation pit dewatering is tested and studied on site, the safety coefficient of the cofferdam is given by using the foundation calculation software of port engineering, and the specific position of the potential slip surface of the foundation is determined, finally, the optimal design and stability analysis of the current cofferdam structure are carried out, the results show that: the cofferdam has the problem of leakage, so the corresponding water isolation measures should be taken, and the foundation pit dewatering causes large horizontal displacement of the foundation, the sliding failure surface occurs in the muddy clay layer; the cofferdam has instability and leakage problems, in order to meet the safety of later construction, the structure of the cofferdam should be optimized; combined with the distribution law of the failure surface of foundation slip, the optimization scheme of driving steel sheet pile in the inner side of cofferdam core soil is put forward; it is verified that the steel sheet pile cofferdam can meet the stability needs of foundation pit during dewatering and after excavation, which is a reasonable and effective support scheme.

In order to further provide a basis for determining the reasonable sealing depth of the coal seam drainage hole, based on the geological data of the W33011 working face of Sihe Mine, the FLAC3D numerical simulation software is used to analyze the stress, displacement, and plastic zone of the surrounding coal body after the excavation of the W33011 roadway in Sihe Mine. And the distribution law of vertical stress, horizontal stress, vertical displacement, horizontal displacement and elastoplastic failure characteristics of the coal body around the roadway are obtained.

In order to find the main control factors that affect oil-water distribution in Gulong syncline, the oil-water distribution law and main control factors of Gulong syncline in Gulong South were analyzed based on comprehensive evaluation. The research shows that Putaohua oil reservoir in Gulong syncline area of southern Gulong is mainly lithologic oil reservoir under structural background, and the distribution law of oil and water is controlled by structure, sedimentation and reservoir physical properties. The distribution characteristics of reservoir physical properties are the main factors that control the distribution of oil and water in this area. This paper optimizes the reserves on the basis of recognizing the distribution of oil and water, and finally delineates the area of the well potential area X.Xkm2.

There are many factors that affect the distribution of remaining oil after polymer flooding, and different geological conditions, production methods and production systems will affect the distribution characteristics of remaining oil. In this paper, the control degree parameters of polymer flooding are used to quantitatively measure the remaining proportion of four types of microscopic residual oil after polymer flooding, namely cluster, membrane, blind end and corner, and it is concluded that different types of microscopic residual oil have different reduction ranges after polymer flooding. The microscopic remaining oil distribution law of different displacement intensity positions at high, medium and low levels is summarized. After polymer flooding, the remaining oil distribution is more concentrated, and the oil saturation in the remaining oil-rich area is higher, which is distributed in strips and sheets. The main enrichment areas of remaining oil are near faults and sandstone pinchouts. The residual oil for polymer drive has a limited effect, and the development difference in the subsequent water drive stage still exists.

XX oilfield has been put into polymer flooding development for 24 years, with cumulative oil production reaching XX million tons. Since 2005, the first-class reservoirs of early polymer flooding have been transferred to subsequent water flooding. After long-term water flooding, polymer flooding and subsequent water flooding, these reservoirs are in the development stage of “double extra high”, with high reservoir production degree, serious ineffective circulation and highly dispersed remaining oil, which makes it difficult to further tap potential. Therefore, the remaining oil potential and distribution law are studied in the first class oil layer in XX area of oilfield, which provides geological basis for further development and adjustment of EOR.

By analyzing the basic theories and technical principles of managed pressure drilling, this paper establishes the cyclic pressure loss check and ECD calculation model under managed pressure conditions. The model is used to calculate and analyze the distribution of equivalent density curves in the wellbore under different drilling fluid densities and different pressure control conditions, and to analyze the distribution of ECD curves in pressure profiles at the same depth. Analyze the density range of the safe use of drilling fluid.

The initial geostress field is an important basis for the design and stability analysis of geotechnical engineering. The geostress field of the whole engineering area must be calculated by inversion analysis with the limited geostress data, because there are few measured geostress points. Based on the geological background of a tunnel in northern Hebei province and considering the influence of regional highly weathered, moderately weathered and slightly weathered stratum on the stress field, the 3D finite difference method and multiple linear regression method were used to calculate the three-dimensional geological model of the study region to get the optimal regression coefficient. It is found by comparing the regression value with the field measured value that the two values are equal in magnitude and close in direction, indicating that the geostress field calculated by regression is reasonable, then the distribution law of the geostress field in the study area is further analyzed on this basis. The results show that there is a stress concentration in the tunnel center, z peaking at 50m below the center, and decreasing in the left and right direction with a large stress gradient then getting out of the area of stress concentration and tending to be stable. The study area is a medium geostress area, based on gravity stress, the control effect of gravity stress field is gradually enhanced with the increase of buried depth. The research results have important value in the design and construction of tunnel in special geological conditions.

A one-dimensional lattice percolation model is constructed for the bond problem at flowing along non-nearest neighbors. Arbitrary parameters were taken (percolation radius, number of nodes in a one-dimensional lattice and number of experiments). Based on original algorithms operating on a computer faster than standard ones, the values of the percolation threshold were obtained with the corresponding error. Based on these data, the hypothesis about the normal distribution of the percolation threshold is tested. Using Pearson’s criterion it was shown for the first time that there is no reason to reject this hypothesis for one-dimensional problems of bonds and sites with an arbitrary percolation radius.

In view of the complicated geological stress structure and fuzzy distribution characteristics of a kilometer-deep mine, the KX-81 hollow inclusion stress relief method was used to test in situ stress in Shuanghe Coal Mine at the level of –1100. On the basis of the field test data, the 3D grid diagram of the principal stress distribution in the deep mining area of Shuanghe Coal Mine was drawn, and the relationship between the in situ stress distribution characteristics and the fault structure in wellfield was studied. Results showed that 1) the directions of σ1 and σ3 at each measurement point were horizontal, and the other principal stress σ2 was vertical. 2) The maximum principal stress value was 1.26–1.48 times of the self-weight stress value, indicating that the horizontal tectonic stress plays a leading role in the in situ stress of the mine. 3) The horizontal and vertical stresses at a depth of about 1090 m were estimated according to the theory. A comparison revealed that the theoretical values were lower than the field measured values. The area was found to be dominated by horizontal tectonic forces belonging to the dynamic stress field. 4) The direction of σ1 at each measurement point was 114.70°–124.72°, with an average of 120°. The direction was NWW-SEE. In accordance with the distribution law of the fault structure in the wellfield, the consistency between the wellfield geological structure and the measured direction of the maximum principal stress was analyzed and verified. The research results provide technical basis for deep well roadway layout and stability control and improve the scientific nature and reliability of surrounding rock control of high stress roadway in deep wells under complex geological structures.

In the process of subway open-cut station construction, excavation deformation seriously threatens the safety of municipal pipelines and buildings. To ensure the effectiveness of grouting reinforcement, drilling exploration and pressure water test were conducted on the basis of the grouting reinforcement project of the excavation of an open-pit station in Qingdao metro, the permeability coefficient and crack characteristics were studied, and the equivalent crack width was calculated on the basis of cubic law. To determine the injectability index of grout and realize the optimal selection of grouting materials, the statistical distribution law of the equivalent crack width was analyzed on the basis of the Pareto distribution, and an effective method of grout selection was proposed. The PQT curve in the grouting process was analyzed by flow dimension theory to realize the dynamic adjustment of the grouting process. Finally, the grouting reinforcement effect was evaluated on the basis of the core sample and borehole TV. Results show that if the permeability coefficient is subject to Pareto distribution with parameters tmin and k, then the distribution curve of the permeability coefficient in the logarithmic coordinate is a straight line; the equivalent crack width obtained on the basis of the cubic law is also subject to the Pareto distribution with parameters bmin and 3k. Therefore, the equivalent crack width distribution curve can be obtained to provide a basis for the grout selection.

Characteristics and distribution of the weld porosity are observed by using OM and SEM after as-cast magnesium alloy AZ91D is welded by CO2 laser. And then the formation model of two types of porosity is established by use of organization composition and distribution of metal base. Besides, the mechanism of pores in welding is explained on three aspects including microscopic porosity, macroscopic porosity and escape of bubbles. Based on these models and mechanisms, the shape characteristics and distribution of a welding porosity in a welding seam is explained and the formula of bubbles escape is also given. In addition, the measures to prevent welding porosity are discussed preliminarily. And based on the preliminary research on this topic, when (0.2%Ca+0.4%Y) is added to AZ910D magnesium alloy and high strain rolling is used, the laser weld porosity ratio of magnesium alloy can be effectively reduced.

This paper analyzes the static load of the ROPS side loading test-bed of the mine dump truck by using the finite element method, obtains the distribution law of the stress and deformation, discusses the feasibility of the simulation analysis, and makes a beneficial exploration for the design and improvement of the similar ROPS in the future.

In order to reasonably determine the maximum and minimum vehicle speed limit values at night and ensure the driving safety in the maintenance area of expressway, the distribution law of vehicle speed at night in the maintenance area of expressway is studied. Based on the investigation of one-way lane closure construction in the four-lane maintenance area of expressway, the location speed of the main traffic control area in the night maintenance area is analyzed, and the average speed, 85% vehicle speed, the speed difference in different areas and the speed difference in heavy-duty vehicle(HDV) and light-duty vehicle(LDV) workshops are determined. The results show that the standard deviation of vehicle speed distribution from warning area to transition zone to construction area is obviously reduced, and the speed difference between HDV and LDV is also obviously reduced. Finally, according to the distribution characteristics of night speed, the night speed limit model of maintenance operation area is given, the speed limit values of different models are calculated respectively, and the night perceived speed model is used to modify the speed limit value.

If the safe concentration of gas in coal mine exceeds the upper limit, it will bring great risks to coal mine production. Therefore, it is of great significance to study the distribution law of gas concentration on coal face. This paper established the layout plan of gas sensor, measured the gas concentration of each observation point under the wind speed of 3m/s, established the trend surface model of first order to fifth order, and solved the trend surface equation of each order, obtained the best trend surface equation through a variety of testing methods, and studied the gas distribution and migration rules in detail.

Methods of approximation for the distribution law of experimental data find wide application in problems of reliability assessment in tests of both hardware and software of software modules of information-measuring and control systems (SM IMCS). Thus, the main task is to solve the problem of increasing the accuracy of the approximation and simplify experimental data processing. In this paper various modification types of Pearson distribution for data taking both positive and negative values, and for data taking only positive values are considered. The described modifications allow one to solve a range of problems related to the existing distributions, as well as to improve the simplicity of the approximation procedure. Pearson logarithmic distributions are proposed for experimental data that take only positive values.

Taking Wumeng mountainous area in Guizhou province as the study area, by collecting landslide data and on-the-spot investigation records, a spatial database of 939 landslides and related influencing factors on GIS platform are established. The influence of altitude, relative height difference, slope angle, slope aspect, the shortest distance from landslide to rivers is studied. The results show that the number of landslides decreases exponentially with the shortest distance to the rivers. The most important factor affecting landslides distribution is topography and morphological, especially slope. The research can help human beings get along better with the surrounding nature environment and provide a basis and reference for environmental governance, landslide prevention and mitigation work.

The distribution law of acid rain in China is counted, and the operation of power grid equipment in acid wet deposition area is investigated. It is found that southern China has the strongest acidity of precipitation in the country. The ratio of SO4 2-, N03 -, NH4+, Ca2+ concentration in acid rain is higher. Acid rain causes serious corrosion of transmission line and transformation equipment in Shandong, Sichuan, Shanxi and Henan provinces of China. The acid rain and corrosion products aggravate the dissolution and chemical reaction of the original dry deposition pollution on the external insulation surface of power grid, which may lead to corrosive flashover.

In order to explore the large mining height are broken coal seam fully mechanized working face goaf spontaneous combustion “three zones” under the different height of distribution, through the establishment of numerical model, builds the working face goaf spontaneous combustion “three zones” three-dimensional sampling analysis system, through the analysis of oxygen, carbon monoxide, carbon dioxide and other coal spontaneous combustion index gases change law of goaf spontaneous combustion dangerous area under different heights for the division, the goaf three-dimensional spontaneous combustion dangerous area is determined. The results show that the “spontaneous combustion zone” of goaf in fully mechanized coal face of large mining height gradually widens along the vertical height, and the spontaneous combustion risk area becomes larger.

The Shaan 209 area of the 2nd section of Yulin gas field is a water-rich area. The water production of most wells is too large, which seriously affects the production of gas wells in the well area. Based on the research foundation work area formation water chemistry characteristics and distribution of the testing, laboratory analysis based on existing formation water, combined with geochemical classification, analysis of the formation water type, cause, distribution of well Shaan 209 in Yulin south area, the main control factors of the formation water in the working area are identified. Therefore, it is demonstrated that the Shan 2 section of water-rich area still has development potential, which provides a basis for the optimization of management strategies in the rich water area, and lays a foundation for the scientific and efficient development of the Yulin South area.

The Weiyuan and Anyue large gas fields discovered on the Leshan-Longnvsi paleo-uplift in Sichuan Basin have the oldest marine gas reservoir discovered in China so far, and Weiyuan is also the first gas field to utilize helium resources in China. The Helium in natural gas of Leshan-Longnvsi paleo-uplift belongs to crust-derived helium formed by radioactivity, and its content distribution shows obvious regularity. The content of helium is highly correlated with the age of reservoir in the same gas field, and the helium content is gradually increased from the top to the bottom. However, the content of helium in natural gas presents significantly different in various tectonic units. The content of helium in Anyue gas field developed on Gaoshiti-Moxi structure is very low. The average contents of Sinian and Cambrian are 0.0356% and 0.0078%, respectively. The content of helium in Weiyuan gas field developed on Weiyuan structure is relatively higher, and the average contents of Sinian and Cambrian are 0.28% and 0.18% respectively. The high helium content of natural gas in Weiyuan gas field is related to the large-scale granite body developed on the basement on the one hand and the water-soluble gas accumulation on the other hand. The main gas reservoirs in the Weiyuan gas field and adjacent areas are located in the Sinian system. From the slope area to the high point of the Weiyuan structure, the helium content has increased significantly. With the tectonic movement of the Himalayan period, the Weiyuan area is greatly uplifted, causing structural traps. Natural gas dissolved in the water, including helium gas, is decomposed by decompression, and the released gas is trapped, then released gases accumulated in traps and thus formed Weiyuan gas field with high content of helium.

The reservoir flood control risk is closely related to the accuracy of hydrological forecasting. High-accuracy hydrological forecasting technology can greatly reduce the reservoir flood control risk. Based on the definition of reservoir flood control risk, the risk exceeding the check water level of the reservoir and the risk exceeding safe flow of downstream flood control object are selected as the risk index of reservoir flood control in this paper. The relationship between the standard deviation of the relative error and the certainty coefficient of the flood process is analyzed. According to the distribution law of the flood forecast error, the Monte Carlo method is used to generate multiple inflow scenarios to simulate the flood control operation of reservoirs and analyze the risk rate of reservoir flood control operation. Taking Xiluodu and Xiangjiaba cascade reservoirs as an example, the risk rate of exceeding the check water level of the reservoir and exceeding safe flow of downstream flood control object under different flood forecasting accuracy are calculated. It provides a scientific basis for flood forecasting and operation of Xiluodu and Xiangjiaba cascade reservoirs.

The method of solution of differential equation for moisture motion in the atmosphere based on the equation with random parameters is considered. The experimental distribution law for random parameters is obtained and discussed. Analytical expression for density distribution of specific humidity in the image space is provided.

Dust is an important part of the particulate matter in the desert atmosphere environment . It moves to the nearby solar panels by suspension and saltation, which affects solar power. Collecting sand dust with sand sampler and compare with the dust distribution characteristics and parameters on the earth's surface to find out the transport law of dust and variation of dust weight with height in sand sampler. The results showed that the distribution of dust particle size obeyed the exponential distribution law. The dust particle size of surface dust is larger than that of sand sampler and the dust is in poor sorting which was caused by the selection of external factors such as wind. There is a good correlation between the dust in the sand sampler and the specific gravity of dust particle size in the earth's surface. The dust weight increases with height in sand sampler obey the law of power-decreasing. The heigher the solar panel, the surface dust deposition has less influence on it. The results will provide a theoretical basis for the impact of desert dust on solar power station.

Longmen Grottoes was afflicted with many diseases for a long period such as weathering, seepage water and organism growth. Those adverse factors were threatening to preserve cultural relic. Longmen Grottoes conservation and restoration project being put into effect by UNESCO in 2002. The Longmen Grottoes area environmental monitoring system was built in order to comprehensively master the distribution law of environmental factors over the Longmen Grottoes. The monitoring items contains temperature, humidity, wind direction, wind speed, precipitation, light intensity,water content in soil, the rock surface temperature and so on. At the same time, monitoring three experiment caves, monitoring the inside temperature, humidity, seepage water and the wall face temperature etc. So as to analyze the relationship between cave environment and regional environment. We statistical and arrange the data using Excel software, Kgraph software and DPS software. Through the grey incidence analyze, the incidence matrix and the correlation degree of the environmental factors was obtained[1]. The main environment factors for the formation of the disease had been researched. Based on the existing environmental monitor data, the relevance of seepage water and fracture displacement with other environmental factors had been studied, and the relational order was obtained. Corresponding preventive measures were put forward by the formation mechanism analyze of the disease.

According to the fluid similarity theory, the simulation experiment system of mining tunnel fire is established. The grid division of experimental model roadway is carried on by GAMBIT software. By setting the boundary and initial conditions of smoke flow during fire period in FLUENT software, using RNG k-Ɛ two-equation turbulence model, energy equation and SIMPLE algorithm, the steady state numerical simulation of smoke flow velocity in mining tunnel is done to obtain the distribution law of smoke flow velocity in tunnel during fire period.

In order to study the influence of inert gas injection to gas explosion in the process of fire zone sealing, tunnel fire model was established by COMSOL software, and numerical simulation is carried out to study change laws of flow field and concentration field in the process of fire zone sealing. Through comparing the distribution law of flow field and concentration field whether the inert gas injection and different flows, obtained the influence of inert gas injection to gas explosion in the process of fire zone sealing. As the decrease of entrance average wind speed, the maximum wind speed in the centre vertical section of tunnel gradually reduces. when the entrance average wind speed is 1m/s, counter current layer is produced near the fire resource, length and thickness of counter current layer and maximum current speed rises with the declining of the entrance average wind speed, and swirl will be formed when the entrance average wind speed is less than 0.01m/s. In the process of fire zone sealing, the maximum gas concentration in the fire area and on the side of leeward goes up with the declining of the entrance average wind speed, the nitrogen concentration will gradually increase with the declining of entrance average wind speed.

The work describes mathematical model of non-stationary heat and mass transfer processes in dispersed environment, taking into account the phase transition; presents the results of numeric modelling for conditions of direct reduction in high-temperature reducing atmosphere, corresponding to the direct reduction in the jet-emulsion unit according to the principles of self-organization. The method was developed for calculation of heat and mass transfer of the aggregate of iron material particles in accordance with the given distribution law.

After introducing the formalism of maximum entropy and reviewing alternative approaches for fragment size statistics, this paper derives a general distribution law (similar in form to the Bose-Einstein statistics) and applies it to distributions observed in rock mining, exploding metallic shells, shattered crystal pieces, droplets in spray, atomic or molecular clusters, space debris and fragmented nuclei. Variations of fragment number with size that are power-law-like (fractal), humped or exponential can lead to physically significant conclusions regarding the fracturing mechanism. Theoretical aspects of the maximum-entropy method in the derivation of the distribution law (including some inherent difficulties) are discussed.