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Investigation of the influences of asphaltene deposition on oilfield development using reservoir simulation

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Petroleum Exploration and development 2022年第5期49卷 1138-1149页

作者： TANANYKHIN D S sTRUCHKOV I A KHORMALI A ROsCHIN P V saint-Petersburg Mining University Saint-Petersburg 199106Russia LLC Tyumen Petroleum Research Center Tyumen 625000Russia department of Chemistry Faculty of Basic Sciences and EngineeringGonbad Kavous UniversityGonbad Kavous 49717-99151Iran LLC samaraNIPIneft Samara 443010Russia

This paper investigates the deposition of asphaltenes in the porous medium of the studied field in Russia and predicts production profiles based on uncertainty evaluation. This problem can be solved by dynamic modeling, during which production profiles are estimated in two scenarios: with and without the activation of the asphaltene option. Calculations are carried out for two development scenarios: field operation under natural depletion and water injection into the aquifer as a reservoir pressure maintenance system. A full-scale compositional reservoir simulation model of the Russian oilfield was created. Within a dynamic simulation, the asphaltene option was activated and the asphaltene behavior in oil and porous medium was tuned according to our own special laboratory experiments. The model was also matched to production historical data, and a pattern model was prepared using the full-scale simulation model. Technological and the asphaltene option parameters were used in sensitivity and an uncertainty evaluation. Furthermore, probable production profiles within a forecast period were estimated. The sensitivity analysis of the pattern model to input parameters of the asphaltene option allowed determining the following heavy-hitters on the objective function: the molar weight of dissolved asphaltenes as a function of pressure, the asphaltene dissociation rate, the asphaltene adsorption coefficient and the critical velocity of oil movement in the reservoir. Under the natural depletion scenario, our simulations show a significant decrease in reservoir pressure and the formation of drawdown cones leading to asphaltene deposition in the bottom-hole area of production wells, decreasing their productivity. Water injection generally allows us to significantly reduce the volume of asphaltene phase transitions and has a positive effect on cumulative oil production. Injecting water into aquifer can keep the formation pressure long above the pressure for asphaltene precipitation, preventing the asphaltene deposition resul

关键词： oilfield development asphaltene deposition uncertainty evaluation sensitivity analysis compositional reservoir simulation

Thermal inertia at the MsL and Insight mission sites on Mars

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Earth and Planetary Physics 2022年第1期6卷 18-27页

作者： d.singh s.Uttam Centre of studies in Resources Engineering Indian Institute of Technology BombayMumbaiIndia Physical Research Laboratory AhmedabadIndia

For planetary surface materials,thermal inertia is the critical property that governs the surface’s daily thermal response and controls diurnal and seasonal surface temperature variations.Here we use the ground measurements made by the MsL Curiosity rover and the Insight lander to determine the thermal inertia of two sites on Mars.This study compares the variation of thermal inertia during and after the Large dust storm(Lds)of Martian Year(MY)34.To determine surface thermal inertia,we derive a simple approximation(using energy balance),which utilizes surface albedo,surface energy flux,and diurnal change in the surface temperature.The average thermal inertia in MY34 is about 39.2%,3.7%,and 3.4%higher than MY35 average thermal inertia for the MsL,Insight(FOV1),and Insight(FOV2),respectively.Notably,the thermal inertia at the Insight(FOV1)is consistently lower by about 20 J·m^(-2)·s^(-1/2)·K^(-1) than the Insight(FOV2)site for all scenarios,indicating variation in the region’s surface composition.The best-fit surface albedo in MY34(determined using the KRC model)are about 0.08,0.05,and 0.03 higher than MY35 surface albedo for the MsL,Insight(FOV1),and Insight(FOV2),respectively.An increase in both surface albedo and thermal inertia during the Lds indicates that the underlying surface is both more thermally resistant and more reflective than the overlying loose dust.

关键词： Mars Mars surface thermal inertia dust storm Mars climate

Flexural-wave-generation using a phononic crystal with a piezoelectric defect

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Applied Mathematics and Mechanics(English Edition) 2023年第8期44卷 1241-1262页

作者： s.H.JO d.LEE department of Mechanical Roboticsand Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea department of Mechanical Engineering Seoul National UniversitySeoul 08826Republic of Korea

This paper proposes a method to amplify the performance of a flexural-wave-generation system by utilizing the energy-localization characteristics of a phononic crystal(PnC)with a piezoelectric defect and an analytical approach that accelerates the predictions of such wave-generation performance.The proposed analytical model is based on the Euler-Bernoulli beam theory.The proposed analytical approach,inspired by the transfer matrix and s-parameter methods,is used to perform band-structure and time-harmonic analyses.A comparison of the results of the proposed approach with those of the finite element method validates the high predictive capability and time efficiency of the proposed model.A case study is explored;the results demonstrate an almost ten-fold amplification of the velocity amplitudes of flexural waves leaving at a defect-band frequency,compared with a system without the PnC.Moreover,design guidelines for piezoelectric-defect-introduced PnCs are provided by analyzing the changes in wave-generation performance that arise depending on the defect location.

关键词： phononic crystal(PnC) defect wave-generation fexural wave analytical model

Flexible ultra-thin super-resolution endoscopy

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science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 171-172页

作者： George s.d.Gordon department of Electrical and Electronic Engineering University of NottinghamNottingham NG7 2RDUK

In recent years, multimode fiber(MMF) has become an important tool for high-resolution endoscopic imaging in narrow channels(e.g., in the brain via needles or inside blood vessels) due to its high mode density and fine diameter, typically stacle to widespread deployment in applications is that realistic perturbations, including bending, twisting and changes in temperature, cause unacceptable image degradation.

关键词： fiber resolution typically

Impacts of weaning weights and mycotoxin challenges on jejunal mucosa-associated microbiota,intestinal and systemic health,and growth performance of nursery pigs

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Journal of Animal science and Biotechnology 2022年第5期13卷 1440-1457页

作者： d.M.Holanda s.W.Kim department of Animal science North Carolina State UniversityRaleigh 27695USA

Background:This study aimed at investigating the effects of mycotoxin challenge on the growth and physiology of nursery pigs with different weaning weights.Results:At weaning,10 pigs were euthanized to collect jejunal mucosa and 90 pigs were assigned following a randomized complete block design in a 2×2 factorial arrangement of treatments with 3 pigs per pen.Factors were:weaning weight(light:body weight,BW9.0 kg);and dietary mycotoxins(supplementation of 0.2 mg/kg aflatoxins,2.0 mg/kg deoxynivalenol).All diets had titanium dioxide as an external marker at 0.5%.Growth performance and fecal score were recorded until pigs achieved 20 kg BW(light pigs average BW=21.1 kg and heavy pigs average BW=20.5 kg).Pigs were sampled for blood,ileal digesta,jejunal tissue and mucosa at 20 kg BW.data were analyzed using the mixed procedure of sAs.At weaning,light pigs had decreased(Psed(Psis factor-α,and increased(Pdiversity indexes of jejunal mucosa-associated microbiota.At 20 kg of BW,light pigs had decreased(Pdaily gain(AdG),average daily feed intake(AdFI),and gain to feed ratio(G/F).Mycotoxins decreased(PdG,AdFI,and G/F.Light pigs tended to have increased fecal score on d 0(P=0.080),d 10(P=0.069),and increased(Pscore at 20 kg.Mycotoxins decreased the apparent ileal digestibility of nitrogen(Ps had increased(Pstinal malondialdehydes and interleukin 8.Mycotoxins tended to increase(P=0.060)intestinal tumor necrosis factor-α.Conclusions:Nursery pigs with light weaning weight were more susceptible to jejunal inflammation and had impaired intestinal health due to weaning stress,whereas mycotoxins diminished the health and growth of nursery pigs regardless of weaning weight.

关键词： Growth Health Mycotoxins Nursery pig Weaning weight

Optical theorem,crossing property,and derivative dispersion relations:implications on the asymptotic behavior of σ_(tot)(s) and ρ(s)

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Chinese Physics C 2022年第8期46卷 72-90页

作者： s.d.Campos V.A.Okorokov Applied Mathematics Laboratory-CCTs/dFQM Federal University of São CarlosSorocaba CEP 18052-780Brazil Moscow Engineering Physics Institute National Research Nuclear University MEPhI115409 MoscowRussia

In this paper,we present some results on the behavior of the total cross section and p-parameter at asymptotic energies in proton-proton(pp) and antiproton-proton(pp) collisions.Hence,we consider three of the main theoretical results in high energy physics:the crossing property,derivative dispersion relation,and optical theorem.The use of such machinery facilitates the derivation of analytic formulas for a wide set of the measured global scattering parameters and some important relations between them.The suggested parameterizations approximate the energy dependence for the total cross section and ρ-parameter for pp and pp with a statistically acceptable quality in the multi-TeV region.Additionally,the qualitative description is obtained for important interrelations,namely difference,sum,and ratio of the antiparticle-particle and particle-particle total cross sections.despite the reduced number of experimental data for the total cross section and p-parameter at the TeV-scale,which complicates any prediction for the beginning of the asymptotic domain,the fitting procedures indicates that asymptotia occur in the energy range 25.5-130 TeV.Moreover,in the asymptotic regime,we obtain α_(P)=1.A detailed quantitative study of the energy behavior of the measured scattering parameters and their combinations in the ultra-high energy domain indicates that the scenario with the generalized formulation of the Pomeranchuk theorem is more favorable with respect to the original formulation of this theorem.

关键词： optical theorem derivative dispersion relations asymptotic behavior Pomeranchuk theorem

Logarithmic Regge pole

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Chinese Physics C 2020年第10期44卷 41-50页

作者： s.d.Campos Applied Mathematics Laboratory-CCTs/dFQM Federal University of Sâo CarlosSorocabaSão Paulo CEP 18052780Brazil

This work presents the subtraction procedure and the Regge cut in the logarithmic Regge pole approach.The subtraction mechanism leads to the same asymptotic behavior as previously obtained in the non-subtraction case.The Regge cut,in contrast,introduces a clear role to the non-leading contributions for the asymptotic behavior of the total cross-section.From these results,some simple parameterization is introduced to fit the experimental data for the proton-proton and antiproton-proton total cross-section above some minimum value up to the cosmic-ray.The fit parameters obtained are used to present predictions for the ρ(s)-parameter as well as to the elastic slope B(s)at high energies.

关键词： Regge pole double pomeron ρ-parameter total cross section

Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 819-836页

作者： d.LEE s.CHANG J.LEE department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea school of Mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea department of Mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random inputs.The method consists of a generalized polynomial chaos expansion(GPCE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data set.In the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to random inputs.This allows for avoiding repeated computations of invariant substructures while generating the input-output data set.Combining substructuring with static condensation further improves the computational efficiency of the reanalysis without losing accuracy.Consequently,the GPCE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional inputs.The numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPCE using full finite element analyses(FEAs).We also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)random inputs.

关键词： forward uncertainty quantification(UQ) generalized polynomial chaos expansion(GPCE) static reanalysis method static condensation substructuring

Hash-Indexing Block-Based deduplication Algorithm for Reducing storage in the Cloud

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Computer systems science & Engineering 2023年第7期46卷 27-42页

作者： d.Viji s.Revathy department of Computer science and Engineering Sathyabama Institute of Science and TechnologyChennaiIndia

Cloud storage is essential for managing user data to store and retrieve from the distributed data centre.The storage service is distributed as pay a service for accessing the size to collect the data.due to the massive amount of data stored in the data centre containing similar information and file structures remaining in multi-copy,duplication leads to increase storage space.The potential deduplication system doesn’t make efficient data reduction because of inaccuracy in finding similar data analysis.It creates a complex nature to increase the storage consumption under cost.To resolve this problem,this paper proposes an efficient storage reduction called Hash-Indexing Block-based deduplication(HIBd)based on segmented Bind Linkage(sBL)Methods for reducing storage in a cloud environment.Initially,preprocessing is done using the sparse augmentation technique.Further,the preprocessed files are segmented into blocks to make Hash-Index.The block of the contents is compared with other files through semantic Content source deduplication(sCsd),which identifies the similar content presence between the file.Based on the content presence count,the distance Vector Weightage Correlation(dVWC)estimates the document similarity weight,and related files are grouped into a cluster.Finally,the segmented bind linkage compares the document to find duplicate content in the cluster using similarity weight based on the coefficient match case.This implementation helps identify the data redundancy efficiently and reduces the service cost in distributed cloud storage.

关键词： Cloud computing deduplication hash indexing relational content analysis document clustering cloud storage record linkage