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•Investigation the Microfluidic experiments and studying the effect of Electromagnetic field on the oil recovery factor.•Applying Manganese Oxide nanoparticle for the first time in ...EOR processes.•Investigating the effective Mechanistic tests such as IFT, Viscosity and Wettability Alteration on oil recovery.•Conducting Dynamic Tests in Micromodel in presence and absence of the Electromagnetic field.
The enhanced oil recovery methods such as thermal, chemical, and flooding methods have been utilized for increasing the production of residual oil in reservoirs. In recent years, some researches were conducted on newer methods such as injecting nanofluid and improving its performance utilizing new technologies, i.e., electromagnetic fields to improve oil recovery. In this study, the effect of the electromagnetic field on the oil recovery factor was investigated. First, Iron Oxide nanoparticle was synthesized by the co-precipitation technique and then its surface was functionalized using citric acid. Furthermore, Manganese Oxide nanoparticle which has not used in previous studies in enhanced oil recovery operations despite its suitable electromagnetic properties were used in this research. For analyzing the effect of nanoparticles and electromagnetic field on oil recovery, flooding experiments were performed in micromodel and the results of these experiments were compared to those of flooding without any effect by the electromagnetic field. The Iron Oxide nanoparticles showed better potential in comparison with Manganese Oxide nanoparticles in the oil recovery process. The results showed that by increase in nanoparticles concentration, the oil recovery increases up to 35.45% in the absence of the electromagnetic field. Also, it was observed that the presence of electromagnetic field dramatically increases the oil recovery factor by 79.83 percent. The critical factor for such growth in recovery is the decrease in oil viscosity by almost 950 centipoise, which is due to the temperature increase and possible cracking of heavier components of oil into lighter components. In addition, the Interfacial Tension between oil and nanofluid decreases with increasing the nanoparticles concentration by almost 16 mN/m.
Strong depletions of energetic protons (115–244 keV) were observed during Galileo flyby E26 of Europa. We simulate the flux of energetic protons using a Monte Carlo particle backtracing code and show ...that energetic proton depletions during E26 are reproduced by taking into account the perturbations of the electromagnetic fields calculated by magnetohydrodynamic (MHD) simulations and charge exchange with a global atmosphere and plume. A depletion feature occurring shortly after closest approach is driven by plume associated charge exchange, or a combination with plume associated field perturbations. We therefore conclude, with a new method and independent data set, that Galileo could have encountered a plume during E26.
Plain Language Summary
We investigate why (normally abundant) fast protons were disappearing during Europa flyby E26 by Galileo. We do this by simulating the proton motion. In some cases we detect few protons because Europa is blocking the field of view. What is new here is that part of the decrease can be explained by charge exchange, a process whereby the protons are removed after they lose their electrical charge in Europa's thin atmosphere. Furthermore, we see that there is a special decrease, which can be explained by an erupting plume of water vapor, thereby providing additional evidence for an active plume during Galileo flyby E26.
Key Points
Energetic proton flux depletions during Galileo flyby E26 are driven by inhomogeneous fields, atmospheric charge exchange, and a plume
Plumes can deplete protons through charge exchange and field perturbations
Plumes are a source of energetic neutral atoms
There has been considerable academic interest in the study of nonlinear dynamical models and their exact traveling waves over the past few years. The main aim of the present paper is to consider a ...nonlinear dynamical model known as the nonlinear Konno–Oono model and derive its exact traveling waves. Specifically, after applying a universal transformation, periodic and solitary waves of the governing model with applications in the electromagnetic field are derived using generalized methods. Through the consideration of two- and three-dimensional simulations, several case studies are considered to represent the dynamical behavior of soliton solutions.
Analyses of transformer electromagnetic vibration noise are presented in this study. A finite element model is established which combines transient electromagnetic field analysis, mechanical field ...analysis and acoustic analysis to calculate the sound pressure level of the radiated noise around the transformer. Transient electromagnetic field analysis is performed to get the Lorentz, reluctance magnetic forces and magnetostriction according to Maxwell theory and virtual displacement principle. Mutual influence of strain and magnetisation has been considered. The main frequency components of harmonic electromagnetic excitations are analysed by Fourier transformation so as to carry out the harmonic response analysis and obtain the nodes displacements of the windings and core. The noise distribution is further calculated by acoustic analysis based on the achieved vibration data. Comparison of calculated results and measured data verifies that the combined noise calculating model is applicable for transformer noise prediction.
For the wireless power transfer (WPT) system in electric vehicle (EV) applications, a serious concern lies in the leakage electromagnetic field (EMF) emission. In order to address this issue, this ...article presents a dual-band coil array (DB-CA) with novel high-order circuit (HOC) compensation. The most attractive feature of DB-CA is that both the first and third harmonics of leakage EMF can be reduced simultaneously, while the system still resonates at the same frequency. A detailed mathematical model is established to intuitively reveal the relevance between impedance design and shielding performance, as well as the constraints to achieve resonance. In addition, the novel HOC compensation is employed to decouple the shielding design at each harmonic. Both simulated and experimental results verify the effectiveness of DB-CA, and a 1-kW WPT prototype operating at 85 kHz is established. By applying DB-CA, the leakage EMF can be reduced by 3.88 dB at 85 kHz and 1.84 dB at 255 kHz, respectively. Meanwhile, the system resonant frequency still locates at 85 kHz, and the achieved zero phase angle condition is independent with load condition. It can provide significant guidance to the design of shielding configurations in EV Wireless Charging System.
Concrete compressive strength (CCS) is among the most important mechanical characteristics of this widely used material. This study develops a novel integrative method for efficient prediction of ...CCS. The suggested method is an artificial neural network (ANN) favorably tuned by electromagnetic field optimization (EFO). The EFO simulates a physics-based strategy, which in this work is employed to find the best contribution of the concrete parameters (i.e., cement (
), blast furnace slag (SBF), fly ash (FA1), water (
), superplasticizer (
), coarse aggregate (AC), fine aggregate (FA2), and the age of testing (AT)) to the CCS. The same effort is carried out by three benchmark optimizers, namely the water cycle algorithm (WCA), sine cosine algorithm (SCA), and cuttlefish optimization algorithm (CFOA) to be compared with the EFO. The results show that hybridizing the ANN using the mentioned algorithms led to reliable approaches for predicting the CCS. However, comparative analysis indicates that there are appreciable distinctions between the prediction capacity of the ANNs created by the EFO and WCA vs. the SCA and CFOA. For example, the mean absolute error calculated for the testing phase of the ANN-WCA, ANN-SCA, ANN-CFOA, and ANN-EFO was 5.8363, 7.8248, 7.6538, and 5.6236, respectively. Moreover, the EFO was considerably faster than the other strategies. In short, the ANN-EFO is a highly efficient hybrid model, and can be recommended for the early prediction of the CCS. A user-friendly explainable and explicit predictive formula is also derived for the convenient estimation of the CCS.
An oscillating electromagnetic field weld pool support system combined with a welding sample travel mechanism was designed for improving the weld bead formation in full-penetration laser welding of ...A5083 aluminum alloy. The experimental results show that a proper oscillating electromagnetic field can effectively reduce the weld root sagging. When the root mean square of magnetic induction intensity on the back surface Brms0 = 80 m T and its electromagnetic frequency f = 400 Hz, the weld root sagging for the joint of aluminum alloy plate with thickness of 10 mm can be almost eliminated. The electromagnetic frequency and the laser power have a great impact on the weld root sagging height and the weld back surface roughness, while the influence of magnetic induction intensity is relatively small within its variable range in this study. The analysis of welding joint microstructure shows that the electromagnetic field can also refine the grains to some extent and decrease the width of columnar grain zone, decreasing the cracking susceptibility and improving the mechanical properties of the welding joint. However, the undercut defects are inevitable in full-penetration laser welding of aluminum alloy unless filler wire is used, because the metallic evaporation and splash are unavoidable during the high-power laser welding process.
The electrical activity of neurons depends on the physiological conditions in the nervous system. An electromagnetic field, for example, can significantly affect the dynamics of individual neural ...cells, and it also affects their collective dynamics. It is therefore of interest to study the neuronal dynamics under such an influence in various setups. We thus study the firing patterns in two coupled neurons by considering three different types of synapses, namely electrical, chemical, and electrochemical. We use the Hindmarsh–Rose mathematical model as the basis of neuronal dynamics, and we also introduce an electromagnetic field effect. We conduct extensive calculations of the firing patterns, and we determine the bifurcation diagrams for constant and periodic external currents. The results show that the different synaptic connections evoke different firing patterns and that in general electrochemical synapses can show richer variety of dynamical behavior than electrical or chemical synapses.
MSC Biophysical Stimulation
In article number 2304821, Rajendra K. Singh, Jung‐Hwan Lee, Hae‐Won Kim, and co‐workers demonstrate that biophysical multiple cues coordinated from electromagnetized ...Au‐nanoparticles‐decorated polymer nanofiber under electromagnetic fields significantly regulate the adhesion, alignment, proliferation, and lineage commitment of hMSCs. Without the EMF, matrix cues of electrical conductivity and nanodotted fibrous topography accelerate the anchorage and spreading of hMSCs.
•The fouling inhibition characteristics of an electromagnetic field is studied.•The electromagnetic field inhibits the deposition of CaCO3 fouling.•The electromagnetic field promotes CaCO3 formation ...in aragonite.•An evaluation index is proposed to define the fouling inhibition effect.•The fouling inhibition characteristics presents an extremum feature.
Forced convective heat transfer and CaCO3 deposition experiments were performed to investigate fouling inhibition characteristics of a variable frequency electromagnetic field on the CaCO3 fouling of a heat transfer surface and three indicators, namely, fouling resistance, conductivity, and scanning electron microscope (SEM), were analyzed. Experimental results indicated that the variable frequency electromagnetic field could effectively inhibit the CaCO3 fouling deposition on the heat transfer surface and slow down the growth rate of CaCO3 fouling by influencing aqueous solution and fouling forming ions. Moreover, the variable frequency electromagnetic field could reduce the conductivity of the test fluid, increase both the total precipitation and the bulk precipitation, and promote the CaCO3 crystallization in aragonite rather than calcite to form muddy soft fouling that was readily washed off by the fluid flow. An evaluation model was proposed to better define the fouling inhibition effect of the variable frequency electromagnetic field in the whole period of CaCO3 deposition. The fouling inhibition characteristics of the variable frequency electromagnetic field presented an extremum feature. The minimum fouling resistance was 1.1 × 10−4 m2⋅K/W obtained at 1 kHz, during which the fouling inhibition rate was 64.7% and the average growth rate of CaCO3 fouling dramatically decreased by 61.0% compared with that of the blank test. This work can provide sound theoretical guidance for future application of electromagnetic fouling inhibition technology in the heat transfer enhancement.
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