Field Analysis Research Articles

Comprehensive Basin Analysis and Petroleum Potential Evaluation of Ayoluengo Oil Field, Basque-Cantabrian Basin, Spain

This study presents a comprehensive basin analysis and petroleum potential evaluation of the Ayoluengo oil field in the Basque-Cantabrian Basin, Spain. Using an integrated approach combining geological, geophysical, and geochemical data, we analyzed the basin's evolution and petroleum system elements. The dataset included 2D and 3D seismic data, well logs, formation tops, and geophysical maps. Our analysis revealed a complex structural framework characterized by salt diapirism and halokinetic structures. Well log interpretation and sequence stratigraphic analysis identified two genetic sequences with associated systems tracts. Four reservoir units were mapped, with the main structural traps related to salt diapirs. Seismic facies analysis highlighted high-amplitude convergent (CBH) and high- and low-amplitude convergent (CBHL) facies as the most promising for reservoir quality. The study identified one play (Jurassic) and two prospects: Lias Limestone (80% geologic chance of success) and Carniolas Dolomite (85% geologic chance of success). Volumetric calculations estimate significant hydrocarbon potential, with STOIIP (Stock Tank Oil Initially In Place) ranging from 3.4 to 4.2 x 10^16 barrels for the Lias Limestone reservoir and 1.26 to 1.56 x 10^16 barrels for the Carniolas Dolomite reservoir.

Experimental investigation on in-situ laser-assisted machining of single crystal silicon based on response surface methodology

Abstract In this paper, Response Surface Methodology (RSM) was utilized as a robust and convenient predictive tool to establish the correlation between process parameters in in situ laser-assisted machining and the surface roughness of single-crystal silicon. An optimized design of the diamond tool, a novel temperature field analysis method, and Response Surface Methodology (RSM) were utilized. The contribution rate of each process parameter on surface roughness was laser power > rotation speed > cutting depth > feed rate. The optimal process parameter combination is: rotation speed as 1001 r min−1, feed rate as 4.9 μm/r, cutting depth as 7.55 μm, and laser power as 28.81 W. Experimental validation of these optimal parameters compared surface roughness values obtained experimentally with those predicted. The surface roughness model showed a maximum relative error of 5.2%, with an average error of 4.8% across three experimental sets. These errors are within acceptable limits, indicating an alignment between predicted and experimental results.

Comparison of Elisar-Fast and Sita-Fast Strategy for Visual Field Assessment in Glaucoma.

To compare two fast threshold strategies of visual field assessment: SITA-Fast (SF; Humphrey field analyser) and Elisar-Fast (EF; Advanced vision analyser) in patients with glaucoma. In this cross-sectional observational study, of total 192 subjects, 138 subjects [150 eyes, 80 glaucoma subjects (91 eyes) and 58 healthy controls (59 eyes)] were analysed and included. Each subject underwent 24-2 EF and SF in randomized order with a minimum time interval of 1 hour between tests. Mean test-time, pointwise and sectoral sensitivity, significance of values of mean sensitivity (MS) and global indices [mean deviation (MD) & pattern standard deviation (PSD)] and their correlation. The mean test-time was 2.59±0.25 and 3.38±0.28 minutes (P = 0.001) with SF and EF respectively. Correlation coefficient for pointwise threshold values correlated strongly for both the devices (range from 0.70 to 0.92). The Intra class correlation (ICC) value of ≥ 0.8 was observed across all sectors indicating good reliability. Bland-Altman plot denoted 95% of data for MS values within limit of Agreement (LOA). The ICC values for overall MS, MD and PSD were 0.916, 0.913 and 0.872 respectively indicating good reliability. High degree of correlation was observed for MD (r = 0.912, P=0.00) and PSD values (r=0.732, P=0.00). Comparison of values indicated a difference of 1.09dB for MD and 0.06dB for PSD between both strategies. High degree of correlation existed between the global indices and pointwise threshold values. The study documents the ability of EF to successfully assess visual field in patients with glaucoma.

Laser Construction TiOx-Ag heterostructure interface for high sensitive coupling resonance enhanced fluorescence in bacterial nucleic acid amplification sensor chip

Coupled resonance at the noble metals and metal oxides heterogeneous interface can enhance the fluorescence of molecules. This fascinating direction provides high value for the preparation and engineering design of fluorescence sensing platforms in nucleic acid sensing, pathogen detection and biological imaging. Here, an integrated nucleic acid amplification sensor chip consists of an array of silver nanoparticles/oxygen vacancy titanium oxide (TiOx-Ag) heterostructure substrates. The femA gene of Staphylococcus aureus was amplified and detected by enhancement fluorescence on the integrated chip. The TiOx-Ag heterostructure array was prepared by a laser method, the enhanced fluorescence performance was investigated in detail using calcein as a probe. The optical, electronic structure and plasmonic local field analysis indicate the strong coupling between the fluorescence molecule and the TiOx-Ag crystal plane, which inspired the excellent fluorescence signal of calcein, with an enhancement factor of up to 5. Staphylococcus aureus was detected by the above chip with a detection limit as low as 157 cfu/mL. These methods were applied to the detection of spiked serum samples with good detected performances, providing a powerful tool for rapid and reliable diagnosis of pathogens in medical institutions.

Effect of Gasket Wear Rate on Hydraulic Performance and Internal Flow of Multistage Centrifugal Pump with Floating Impellers

Abstract The sealing gaskets of multistage centrifugal pumps are prone to wear during operation. This study investigates the influence of gasket wear rate on hydraulic performance and internal flow field through numerical simulations. As the wear rate of the gasket increases, both the efficiency and head coefficient of the pump gradually decrease. When the gasket is completely worn out, the efficiency decreases by 5.6% and the head coefficient decreases by 9.5% compared to the unworn gasket condition. Analysis of the internal flow field reveals that the front side chamber is most significantly affected by gasket wear. As the gasket wears, the flow velocity within the front side chamber increases gradually, and the high-entropy production zone expands, thereby affecting the hydraulic performance of the pump. The findings of this study provide practical engineering insights for enhancing the operational performance of multistage centrifugal pumps.

Optical signal characteristics analysis of atmospheric disturbance density fields generated by high-speed aircraft

Aircraft disturbs the adjacent atmospheric environment in flight, forming spatial distribution features of atmospheric density that differ from the natural background, which may potentially be utilized as tracer characteristics to introduce new technologies for indirectly sensing the presence of aircraft. In this paper, the concept of a long-range aircraft detection based on the atmospheric disturbance density field is proposed, and the detection mode of tomographic imaging of the scattering light of an atmospheric disturbance flow field is designed. By modeling the spatial distribution of the disturbance density field, the scattered echo signal images of active light towards the disturbance field at long distance are simulated. On this basis, the characteristics of the disturbance optical signal at the optimal detection resolution are analyzed. The results show that the atmospheric disturbance flow field of the supersonic aircraft presents circular in the light-scattering echo images. The disturbance signal can be further highlighted by differential processing of the adjacent scattering images. As the distance behind the aircraft increases, the diffusion range of the disturbance signal increases, and the signal intensity and contrast with the background decrease. Under the ground-based observation conditions of the aircraft at a height of 10000 m, a Mach number of 1.6, and a detection distance of 100 km, the contrast between the disturbance signal and the background was 30 dB at a distance of one time from the rear of the fuselage, and the diffusion diameter of the disturbance signal was 50 m. At a distance eight times the length of the aircraft, the contrast decreased to 10 dB, and the diameter increased to 290 m. The contrast was reduced to 3 dB at a distance nine times the length of the aircraft, and the diameter was diffused to 310 m. These results indicate the possibility of long-range aircraft detection based on the characteristics of the atmospheric density field.

Hemolysis analysis of centrifugal blood pump based on numerical simulation

Abstract The operation of blood pump will cause mechanical damage to red blood cells and lead to hemolysis. Based on this, CFD technology is used to simulate the three-dimensional flow field of centrifugal blood pump. According to the analysis of velocity field, pressure field and stress field; Based on the hemolysis power function model, the hemolysis performance of blood pump is predicted by Lagrange particle tracking method, and the impeller structure is adjusted to improve its flow performance and reduce the hemolysis index. The research results can provide a basis for the structural improvement and performance improvement of centrifugal heart pump.

Level-set topology optimization with PDE generated conformal meshes

This paper presents a level-set topology optimization approach that uses conformal meshes for the analysis of the displacement field. The structure’s boundary is represented by the iso-contour of a level-set field discretized on a fixed background design mesh. The conformal mesh is updated for each design iteration via a PDE based mesh morphing process that identifies the set of facets in the background mesh that are homeomorphic to the boundary and relaxes the homeomorphic mesh to conform to the structure’s boundary and ensure high element quality. The conformal mesh allows for a more accurate computation of the response versus density and some level-set based methods which interpolate material properties using the volume fraction. Numerical examples illustrate the proposed approach by optimizing linear-elastic two- and three-dimensional structures, wherein insight into the performance of the mesh morphing process is provided. The examples also highlight the scalability of the approach.

Analysis of scalar fields with series convolution

Wave equations for some curved spacetimes may involve functions that prevent a solution in a closed form. In some cases, these functions can be eliminated by transformations and the solutions can be found analytically. In the cases where such transformations are not available, the infinite series expansions of these functions can be convoluted with the power series solution ansatz. We study such an example where the solution is based on a special function.

Design, analysis, and optimization of PMSM for ultra-deep water pile hammer application

With the development of global deepwater oil and gas and offshore wind power resources, there is an increasing demand for ultra-deep water pile hammers (UDPH). In this paper, a permanent magnet synchronous motor (PMSM) with oil fill is proposed for UDPH on the basis of underwater 2500 m depth and 450 kJ impact energy requirements. First, the rated parameters of the PMSM are calculated based on the power required by hydraulic pumps, and then, the method of combining empirical formulas and path algorithms is used to complete the electromagnetic scheme design. Second, finite element analysis of the electromagnetic field is carried out by Maxwell under both no-load and load conditions to verify the rationality of the PMSM. Furthermore, aiming at improving efficiency and reducing cogging, parameter optimization is carried out by a robust parameter optimization design method, and the optimal parameter scheme of the PMSM is obtained. In addition, loss analysis and temperature field coupling calculations of the optimized PMSM are conducted to verify that the temperature of this motor can meet the requirements under different working conditions. Finally, a comparative analysis is conducted between the proposed PMSM and the three-phase asynchronous motor used in the underwater 2,500 m-450 kJ UDPH. The results indicate that the new PMSM introduced in this paper demonstrates significant advantages in terms of weight, volume, and efficiency; moreover, the new PMSM is reasonable and more suitable for UDPH. Therefore, the PMSM proposed in this paper is reasonable and can provide a theoretical basis for improving the traditional UDPH.

Finite element analysis and detection of melanoma cells under dual-cell photoacoustic interference conditions

In order to detect the presence of melanoma cells in two cells under the condition of cell photoacoustic wave interference, this paper conducted a finite element analysis of the photoacoustic wave interference field of two cells. First, the wavelength corresponding to the dominant frequency of the signal from a single red blood cell (mean diameter) was calculated. Then, the distance between two identical red blood cells (mean diameter) was set as a multiple of the wavelength to identify the optimal interference distance and the position of the enhanced zone detection point. Next, under the optimal distance, the signal curves of two cells as red blood cells and when melanoma cells exist in two cells were calculated in sequence. Finally, the frequency domain sound pressure level curve of the detection point under the two states was compared with the single-cell signal to obtain the Frechet distance. The results show that when both cells are red blood cells, the Frechet value is less than 48; when melanoma cells exist in both cells, the Frechet value is greater than 52. This study shows that the presence of melanoma cells in two cells can be determined by adjusting the distance between the cells, arranging the positions of the detection points, and employing the Frechet distance metric curve difference under the condition that the two-cell photoacoustic waves interfere with each other.

The influence of multi-scale fractures on 3D geological modeling of carbonate reservoir: An application case analysis of Anyue Gas Field

Abstract The carbonate reservoirs of the Dengying Formation in the Sinian system are well-developed, but with strong heterogeneity and natural fractures. Conducting three-dimensional fracture modeling research has important guiding significance for deepening the geological understanding and development plan formulation of this gas field. This paper starts from three-dimensional high-precision seismic data, distinguishes cracks of different scales, and uses deep learning technology and Aberrance detection technology to carry out multi-scale crack prediction of the target layer in the research area. Based on this, high-precision crack modeling work is carried out. The on-site construction results show that the natural crack model established by this technology series has high accuracy and has promotional application value in the next step of improving gas field development efficiency.

The Time Evolution of Fast Flavor Crossings in Postmerger Disks around a Black Hole Remnant

We postprocess a three-dimensional, general relativistic, full transport neutrino radiation magnetohydrodynamics simulation of the black-hole-accretion disk-wind system thought to be a potential outcome of the GW170817 merger to investigate the presence of electron lepton number (ELN-XLN) crossings in the neutrino angular distribution. Neutrinos are evolved with an explicit Monte Carlo method and can interact with matter via emission, absorption, or scattering. Within the postprocessing framework, we find ubiquitous occurrence of ELN-XLN crossings at early times (∼11 ms), but this does not hold for later times in the simulation. At postmerger times of ∼60 ms and beyond, ELN-XLN crossings are only present near the equator. We provide a detailed analysis of the neutrino radiation field to investigate the origin and time evolution of these crossings. Previous reports have suggested ubiquitous flavor crossings persisting throughout the simulation lifetime, albeit for different sets of conditions for the merger remnant, the treatment of hydrodynamics, and neutrino transport. Even though we do not perform a direct comparison with other published works, we qualitatively assess the reasons for the difference with our results. The geometric structure and evolution of the ELN-XLN crossings found in our analysis, and by extension, fast flavor instabilities, have important implications for heavy element nucleosynthesis in neutron star mergers.

Simulation-based analysis of welding process parameters for TC4ELI titanium alloy thick-walled cylinders

Abstract In this paper, ABAQUS is used to numerically simulate the residual stresses during welding of titanium alloy thick-walled cylinders. A detailed simulation analysis of the stress field during the welding process is performed by establishing an accurate finite element model, defining the thermal physical properties, boundary conditions, and heat source model, and using the indirect heat-force coupling method. The results of the study show that the distribution of the weld stress field has an important influence on weld quality, material properties, and structural strength. The movement of the welding heat source results in a dynamic change in the stress field, which gives rise to a significant stress concentration at and in the vicinity of the welding heat source.

Identifying Pulsar Candidates in Interferometric Radio Images Using Scintillation

Pulsars have been primarily detected by their narrow pulses or periodicity in time domain data. Interferometric surveys for pulsars are challenging due to the trade-off between beam sensitivity and beam size and the corresponding tradeoff between survey sensitivity (depth), sky coverage, and computational efforts. The detection sensitivity of time domain searches for pulsars is affected by dispersion smearing, scattering, and rapid orbital motion of pulsars in binaries. We have developed a new technique to select pulsar candidates in interferometric radio images by identifying scintillating sources and measuring their scintillation bandwidth and timescale. Identifying likely candidates allows sensitive, focused time-domain searches, saving computational effort. Pulsar scintillation is independent of its timing properties and hence offers a different selection of pulsars compared to time-domain searches. Candidates identified from this method could allow us to find hard-to-detect pulsars, such as submillisecond pulsars and pulsars in very compact, highly accelerated binary orbits. We use upgraded Giant Metrewave Radio Telescope (uGMRT) observations in the fields of PSR B1508+55, PSR J0437−4715, and PSR B0031−07 as test cases for our technique. We demonstrate that the technique correctly differentiates between the pulsar and other nonscintillating point sources and show that the extracted dynamic spectrum of the pulsar is equivalent to that extracted from the uGMRT phased array beam. We show the results from our analysis of known pulsar fields and discuss challenges in dealing with interference and instrumental effects.

Defining the boundaries of the meaning of ornamental compositions in the art of the Pazyryk culture

The article is devoted to the analysis of the semiotic field of the term "ornamental composition" in the context of definitions of ornament and composition in the art of the Pazyryk culture and its historiography. The subject of the study is ornamental compositions from elite burials of the Pazyryk culture of different periods of its development – the early Second Bashadar kurgan and the Tuekta burial ground and the late Pazyryk burial ground. In addition, the paper examines the specifics of the use of the terms "composition" and "ornament" in order to highlight the history of their meanings, as well as analyzes certain provisions of theoretical works on the study of the theory of composition and ornament. The purpose of the study is to identify the components of the semantic field of an ornamental composition related to the field of interaction of the composition with the viewer, and not to the field of meaning of specific figurative images. The article proposes using the method of formal analysis in combination with some provisions of the Gestalt approach described in the works of E. Gombrich and R. Arnheim to analyze a series of ornamental compositions with and without figurative images in the art of the Pazyryk culture. The scientific novelty of the study is predetermined by the absence in the Russian historiography of works describing the specifics of the meaning of ornamental composition in the context of visual perception in the art of the Pazyryk culture. The researchers note that the significance of ornaments in Pazyryk art could be related to the meaning of multi-figure compositions (when zoomorphic images are included in the ornament) and reflect the worldview of the bearers of the Pazyryk culture, or the types of symmetry used in the construction of ornaments could reflect the social structure of society. However, in both of these trends, the analysis of an ornamental composition without figurative images remains outside the scope as a structural and semantic, integral work of art interacting with the viewer. As a result of the research, the assumption is put forward that it is possible to designate a single semantic field for ornamental and multi-figure compositions in Pazyryk art. Clarifying and expanding the scope of the ornamental composition allows us to identify a single specificity of interaction with the viewer of both figurative and non-figurative images of Pazyryk art, to emphasize the game element in the nature of culture.

Modelling and experimental investigation of cooling of field-operating PV panels using thermoelectric devices for enhanced power generation by industrial solar plants

The performance of commercial solar power plants degrades due to an increase in module temperatures for which standard PV-T air or water-cooling techniques are mostly used. In this study, a thermoelectric cooling system is studied for improving photovoltaic cell power efficiency and hence solar power generation. The cooling optimization requires solar cell temperature prediction of field operating PV modules, for which analysis of six models, is presented. The experimentation results show that TEC cooling maintains PV cell at 25 °C whereas PV cell without TEC operates at 55–63 °C, a higher temperature range, showing the effectiveness of the thermoelectric cooling system in precisely controlling PV cell temperature to operate at or near STC conditions in the field creating a temperature difference of 30–38 °C. The NOCT and Faiman model results are found close to the experimental values in comparison to other models. The potential for cooling and a corresponding increase in solar plant energy production is assessed using PV Syst modeling and simulation for three practical PV installation scenarios for 31 different climatic zone locations worldwide showing 6–27 % power loss due to elevated temperatures, which is not studied in previous studies adding novelty to the analysis. The results show that PV-TECS is an effective system to control the temperature of field operating PV modules, which can be used in future photovoltaic power plants. Field results and analysis of PV temperature models is crucial for the optimization and future development of PV-thermoelectric systems deployed under actual outdoor conditions as well as the expected cooling gains in different climatic locations. These aspects are collectively studied in the current work adding to the novelty of the study.

Effect of radial inlet distortion on aerodynamic stability in a high load axial flow compressor

Radial inlet distortion induced by boundary layer separation can significantly affect the aerodynamic performance of the compressor. The effect of radial inlet distortion on the flow structure is numerically investigated in a high load axial flow compressor. The inlet boundary is determined by the experimental results at the downstream of the distortion generator. The results reveal that tip distortion leads to a reduction in the stall margin, whereas hub distortion extends it. Radial distortion redistributes the main flow toward undistorted region due to the obstructive effect of lattice ring. The deficit in axial velocity with tip radial distortion causes the rotor to operate at a higher incidence angle near the casing, while hub radial distortion alleviates the tip blade loading. The detailed three-dimensional flow field analysis indicates that increased blade loading with tip distortion shifts the trajectories of both primary and secondary tip leakage flow toward the leading edge, thereby expanding the blockage region. Conversely, hub radial distortion unloads the rotor tip region, thereby reducing the blockage region induced by tip leakage flow. Additionally, with hub distortion, the location of separation line on the blade suction surface moves closer to the leading edge, and the flow separation around the trailing edge is intensified.

Local Structure and Optical Studies of Mn2+ Doped L-histidine-4- nitrophenolate 4-nitrophenol Single Crystal

Background: The zero-field splitting parameters of Mn2+ doped L-histidine-4- nitrophenolate 4-nitrophenol single crystals are evaluated Methods: The superposition model and perturbation theory are used to obtain zero-field splitting parameters for Mn2+ ion-doped LHPP single crystals. The optical spectra of the system are computed using the crystal field parameters from the superposition model as input into the crystal field analysis program. Results: The evaluated zero field splitting parameters are in good match with the experimental values when local distortion is taken into account. The experimental finding that the Mn2+ ion enters the L-histidine-4-nitrophenolate 4-nitrophenol lattice at the interstitial position is supported by the theoretical result. Conclusion: It is found that the calculated and experimental band positions agree fairly well. Thus, the theoretical study supports the experimental observation.

Study on suction effect of water jet propulsion pump based on entropy weight theory

Water jet propulsion pumps start at special stages such as mooring and sailing, the ship is in shallow water, and the underwater keen clearance (UKC) is relatively small, which is easy to induce underwater suction vortex near the inlet position and cause violent vibration of the pumping unit. The powerful suction effect of the water-jet propulsion pump can draw in debris from the bottom of the riverbed, causing damage to the propulsion pump. This research investigated the suction effect of water jet propulsion pump under different UKC conditions. A flow field analysis method based on the entropy weight theory was constructed to reveal the flow characteristics of the flow field where the underwater suction vortex occurs. The research found that the suction effect on the flow field tends to stabilize under the condition of UKC greater than 2.5D0. After UKC reaches 4.2D0, suction effects essentially cease to create large-scale shear stresses near the riverbed. In addition, this research analyzes the vorticity field using vorticity and net circulation to elucidate the vortex strength within the flow field under different UKC conditions. The probability of generation of underwater suction vortices will be greatly reduced when the UKC is greater than 0.83D0.