Positive Pressure Gradient Research Articles

Numerical simulation and mechanistic model study of gas pocket distribution characteristics in a centrifugal impeller

The formation and extension of the gas pocket in the impeller can lead to the rapid deterioration or even failure of the centrifugal pump's two-phase pressurization. It is difficult to directly measure the characteristic parameters of the gas pocket in the high-speed rotating impeller, such as the void fraction, by experimental methods. In this paper, the two-phase performance of the centrifugal pump is studied by numerical simulation and validated by the experiment. The positive pressure gradient at the end of the blade pressure surface is the main reason why the centrifugal pump can boost at high inlet gas volume fraction (IGVF). As the IGVF increases, both the length and thickness of the gas pocket gradually increase. The head coefficient of the pump has an approximately quadratic relationship with the void fraction in the impeller. The mechanism model of the gas pocket flow is established by the force analysis of the gas pocket and its downstream single bubble in the impeller channel. The model can effectively predict the extension position of the gas pocket and the void fraction in the centrifugal impeller and is validated by numerical simulation.

Characterizing and predicting the partial slip subjected to variable gradients of velocity and pressure in eccentric micro-scale Taylor–Couette flows

In the context of eccentric micro-scale Taylor–Couette flow, variations in localized flow scales result in a non-uniform fluid–solid interface slip state, distinct from the typically studied uniform slip velocity distribution. This study introduces a boundary condition definition method aimed at characterizing partial slip states, complemented by a coupled iterative analysis system tailored to address this complexity. Key contributions include the development of a method for calculating the limiting shear stress, which considers local velocity gradients and pressures. Validation demonstrates that the locally derived slip state aligns more closely with Knudsen number distributions of local flow scales compared to traditional uniform slip models, and exhibits greater consistency with experimentally measured pressure distributions. Additionally, the study reveals that eccentric Taylor–Couette flow, characterized by significant variations in local flow scales and strong self-induced pressure effects, leads to complex distributions of local pressure, velocity gradients, and differences in local slip velocities. Specifically, the non-uniform distribution of local pressure gradients due to eccentricity results in partial slip occurring predominantly on the rotor in regions with positive pressure gradients, and on the stator in regions with negative pressure gradients. Furthermore, the variation in gap height exerts a greater influence on local slip compared to rotational speed and eccentricity ratio. Under certain conditions influenced by pressure gradients, the slip velocity on the rotor may exceed its tangential speed.

Boundary Layer Analysis of a Transonic High-Pressure Turbine Vane Using Ultra-Fast-Response Temperature-Sensitive Paint

Abstract The focus of this article is the impact of surface roughness on the boundary layer caused by a 7YSZ thermal barrier coating (TBC). Experimental investigations are conducted on a NGV installed inside the wind tunnel for Straight Cascades Göttingen (EGG). The shape of the vane has been altered in a way that eliminates the influence of TBC's thickness. Therefore, it is expected that only the surface roughness is influencing the location of the separation and boundary layer transition. The transition next to the roughness can also be affected by positive and negative pressure gradients, separation, and interacting shocks. The impact of TBC on the turbulent wedges' appearance, separation bubble's position and length, and transition location is examined in this study. This research, combined with prior investigations, provides a comprehensive understanding of a turbine vane's aerothermodynamics. To investigate unsteady flow phenomena on a TBC-coated NGV, ultra-fast-response temperature-sensitive paint (iTSP) is utilized. This dataset will serve as a reference point for developing new turbine vane designs that include TBC and extensive cooling. Furthermore, the findings will be employed as a benchmark for improving numerical models.

Simulation of triggering and evolution of ELM by pellet injection in EAST under BOUT++ framework

A BOUT ++ three-field magnetohydrodynamic model is employed to study the triggering and evolution of edge localized mode (ELM) by Li pellets injected along the outer mid-plane in the EAST configuration. The linear simulation shows that compared with a large deposition on the pedestal top (scenario I), a smaller deposition within the steep-gradient pedestal region (scenario II) can stimulate much larger linear growth rates of all-n peeling-ballooning modes (PBMs). The nonlinear simulation shows that there exists a pellet size threshold for ELM triggering for two deposition locations; the threshold for scenario I predicted in the present study matches the EAST observation well. Comparison of the two scenarios reveals that a smaller deposition is sufficient to trigger an ELM in a much shorter time in scenario II, whose ELM size is comparable to that in scenario I. This conclusion confirms previous DIII-D and ASDEX-Upgrade observations, suggesting that the steep-gradient pedestal region is a favorable deposition location for ELM triggering with minimum pellet size. Simulation analyses also find that the positive radial gradient of the hump-like pressure profile in the outer mid-plane induced by the pellet deposition plays a different role in the two scenarios. In scenario I, the force resulting from the gradient hinders the outflow of core plasmas and in return, the perturbation is suppressed from spreading inwards after ELM crashes. In scenario II, with a sizable deposition, the gradient results in another competitive perturbation growth region during the linear phase, thus dispersing the free energy and reducing the efficiency of destabilizing PBMs by pellet injection. The suppressing effect of saturated zonal flow on other modes, the short ELM fast crash phase, and the restricting transport effect of the positive radial pressure gradient work together to constrain the pedestal energy loss, especially when the pellet deposition amount is high.

Effects of CO2 Geosequestration on Opalinus Clay

CO2 geosequestration is an important contributor to United Nations Sustainable Development Goal 13, i.e., Climate Action, which states a global Net-Zero CO2 emissions by 2050. A potential impact of CO2 geosequestration in depleted oil and gas reservoirs is the variations in induced pressure across the caprocks, which can lead to significant local variations in CO2 saturation. A detailed understanding of the relationship between the pressure gradient across the caprock and local CO2 concentration is of utmost importance for assessing the potential of CO2 geosequestration. Achieving this through experimental techniques is extremely difficult, and thus, we employ a coupled Computational Fluid Dynamics (CFD) and Finite Element Method (FEM) based solver to mimic sub-critical CO2 injection in Opalinus Clay under various pressure gradients across the sample. The geomechanical and multiphase flow modelling utilising Darcy Law helps evaluate local variations in CO2 concentration in Opalinus Clay. Well-validated numerical results indicate favourable sub-critical CO2 geosequestration under a positive pressure gradient across Opalinus Clay. In the absence of a positive pressure gradient, a peak CO2 concentration of 5% has been recorded, which increases substantially (above 90%) as the pressure gradient across the sample increases.

Assessing donor-recipient arterial pressure dynamics in STA-MCA bypass for moyamoya disease

BackgroundIn bypass surgery for moyamoya disease (MMD), the superficial temporal artery’s (STA) pressure needs to surpass that of the cortical M4 recipient of the middle cerebral artery (MCA), boosting cerebral blood flow into the MCA and enhancing cerebral circulation. This study investigates the STA-MCA arterial pressure parameters and gradients during bypass surgery, aiming to deepen our understanding of hemodynamic shifts pre- and post-operation.MethodsDSA imaging data were prospectively collected from patients diagnosed with bilateral MMD who underwent STA-MCA bypass surgery between 2022 and 2023 and stratified according to the Suzuki stage. The mean arterial pressure (MAP) of the donor and recipient arteries was directly measured during the STA-MCA bypass procedure, and these data were statistically analyzed and evaluated.ResultsAmong 48 MMD patients, Suzuki grading revealed that 43.8% were in early stages (II and III), while 56.2% were in advanced stages (IV, V, and VI). Predominantly, 77.1% presented with ischemic-type MMD and 22.9% with hemorrhagic type. Pre-bypass assessments showed that 62.5% exhibited antegrade blood flow direction, and 37.5% had retrograde. The mean recipient artery pressure was 35.0 ± 2.3 mmHg, with a mean donor-recipient pressure gradient (δP) of 46.4 ± 2.5 mmHg between donor and recipient arteries. Post-bypass, mean recipient artery pressure increased to 73.3 ± 1.6 mmHg. No significant correlation (r = 0.18, P = 0.21) was noted between δP and Suzuki staging.ConclusionOur study elucidated that cerebral blood pressure significantly decreases beyond the moyamoya network at the distal M4 segment. Furthermore, we observed bidirectional flow in MCA territories and a significant positive pressure gradient between the STA and M4 segments. The lack of correlation between Suzuki stages and M4 pressures indicates that angiographic severity may not reflect hemodynamic conditions before surgery, highlighting the need for customized surgical approaches.

Influence of temperature and pressure gradient on power deposition and field pattern in High Magnetic field Helicon eXperiment

AbstractBased on High Magnetic field Helicon eXperiment, considering the parabolic distribution and Gaussian distribution of radial plasma density, HELIC code was used to study the influence of temperature and pressure gradient on power deposition, electric field, and current density of Helicon Wave Plasma. Three different gradients (positive, negative, and zero gradient) were selected. The results show that positive temperature gradient is beneficial to increase the relative absorption power at the center of plasma. Compared with negative and zero pressure gradients, positive pressure gradient increases the relative absorption power and weakens the current density at the center of plasma, and increases the electric field intensity at the edge of plasma. Larger edge heating will cause the relative absorption power at edge to rise rapidly, which is not conducive to the coupling at the center of plasma. In practical experiments, it is particularly important to reduce the heating effect at edge by cooling the antenna itself. Three different gradients of temperature and pressure have little effect on electric field intensity and current density in plasma, and the variation trend is basically similar, which proves the stability of the antenna mode: m = 1.

3D Turbulent Boundary Layer Separation Control by Multi-Discharge Plasma Actuator

In a subsonic wind tunnel, a three-dimensional separation of a developed turbulent boundary layer was simulated on a swept wing flap model. A multi-discharge plasma actuator operating on the basis of dielectric barrier discharge was used to overcome the positive pressure gradient, leading to a three-dimensional separation, when the ultimate streamline on the aerodynamic surface turns along the flap trailing edge. The actuator created an extended streamwise region of volume force, leading to flow acceleration near a streamlined surface. The influence of the force impact direction relative to the flap trailing edge was studied. The experiments demonstrated that the plasma actuator can significantly influence the flow structure in the separation region, leading to a decrease in both the transverse size of the viscous wake behind the flap and the total pressure losses within it.

Investigation of Lagrangian Areas of Minimal Stretching (LAMS) in a turbulent boundary layer

In this paper the three-dimensional finite-time Lyapunov exponent (FTLE) field of a direct numerical simulation of a flat-plate turbulent boundary layer is analysed in several wall-parallel sections. The data consider a case at a low subsonic Mach number with a moderate positive pressure gradient in the streamwise direction. In contrast to other studies mainly focusing on the maxima of the FTLE field, particular emphasis is placed on the regions of minimal stretching between the vortices and shear layers of the three-dimensional turbulent flow field. These visually appear as contiguous islands or ‘valleys’ between the ‘ridges’ of the FTLE maxima, both at forward and backward integration of the flow field in time. To clearly distinguish the structures investigated from their more common counterparts (e.g. Lagrangian coherent structures, LCS), the acronym LAMS (Lagrangian areas of minimal stretching) is proposed to denote the associated cohesive fluid regions. Consistent with intuition, the largest LAMS occur near the boundary-layer edge, where large regions of homogeneous laminar external flow coexist with upwelling turbulent structures. Compensating for turbulent regions pushing upward, they sink from there down toward the wall, becoming smaller and longer. This process is associated with an increased relative velocity of the LAMS compared with the mean flow, which is observed over the whole boundary layer in the range $y^+ \gtrsim 10$ . Furthermore, it is observed that the Q4 (sweep) events contained in the LAMS clearly dominate over Q2 (ejection) events above $y^+ \approx 10$ . Thereby, local maxima occur at $y^+ \approx 20$ and near the boundary-layer edge. Below $y^+ \approx 10$ , the relationship reverses. Sweeping LAMS from above $y^+ \approx 10$ and ejecting LAMS from below meet in the layer where the maximal vortical activity occurs. The latter is caused by mostly streamwise oriented vortices with maximal vortex stretching in the streamwise direction. Overall, LAMS are associated with cohesive fluid regions between the surrounding vortices and shear layers that both drop down from the boundary-layer edge toward the wall in the outer region of the boundary layer and lift from the wall in the near-wall region.

Significance of Darcy porous and hydro-magnetic dynamical flow with heat transfer of Oldroyd-8 fluid with deferment of nanoparticles in wire coating process

The wire coating method is an engineering development to cover a wire for wadding, motorized forte and ecological protection. In wire coating analysis, moreover, the polymer extruded on the wire is hauled into interior of a die occupied with melted polymer. By considering this significance, the magneto-hydrodynamic flow and heat transmission of Oldroyd-8 constant fluid with suspension of nanoparticles in the wire coating development had been investigated. The fluid with fixed viscosity is considered in porous medium. The flow is conducted with uniform magnetic field. The arising physical governing system is modelled mathematically. The mathematical model is executed by incorporation of thermal radiation and nanoparticles (Embedded in [Formula: see text] nanoparticles). The wire coating is scrutinized mathematically with four cases ([Formula: see text] with constant viscosity and also included in the Reynolds model for constant viscosity. The subsequent flow and heat transmission system were elucidated via the Runge–Kutta technique and the possessions of appropriate governing factors are presented in graphically. The outcome of the current investigation was equated with the previous available outcomes as a specific situation. The results were executed with nanofluid and without nanofluid as well as with positive and negative pressure gradients [Formula: see text]. It is seen that the temperature circulation is augmented due to the upsurge in magnetic parameter M. It is interesting to note that the positive pressure gradient with nanofluid has less momentum distribution compared to rest of the cases. It is also noted that the with negative pressure gradient, the distribution is more compared to positive pressure gradient case.

Small lateral air pressure gradients generated by a large chamber system have a strong effect onCO2transport in soil

AbstractGas transport in soils is usually assumed to be purely diffusive, although several studies have shown that non‐diffusive processes can significantly enhance soil gas transport. These processes include barometric air pressure changes, wind‐induced pressure pumping and static air pressure fields generated by wind interacting with obstacles. The associated pressure gradients in the soil can cause advective gas fluxes that are much larger than diffusive fluxes. However, the contributions of the respective transport processes are difficult to separate. We developed a large chamber system to simulate pressure fields and investigate their influence on soil gas transport. The chamber consists of four subspaces in which pressure is regulated by fans that blow air in or out of the chamber. With this setup, we conducted experiments with oscillating and static pressure fields. CO2concentrations were measured along two soil profiles beneath the chamber. We found a significant relationship between static lateral pressure gradients and the change in the CO2profiles (R2 = 0.53;p‐value <2e‐16). Even small pressure gradients between −1 and 1 Pa relative to ambient pressure resulted in an increase or decrease in CO2concentrations of 8% on average in the upper soil, indicating advective flow of air in the pore space. Positive pressure gradients resulted in decreasing, negative pressure gradients in increasing CO2concentrations. The concentration changes were probably caused by an advective flow field in the soil beneath the chamber generated by the pressure gradients. No effect of oscillating pressure fields was observed in this study. The results indicate that static lateral pressure gradients have a substantial impact on soil gas transport and therefore are an important driver of gas exchange between soil and atmosphere. Lateral pressure gradients in a comparable range can be induced under windy conditions when wind interacts with terrain features. They can also be caused by chambers used for flux measurements at high wind speed or by fans used for head‐space mixing within the chambers, which yields biased flux estimates.

A Turbulent Boundary Layer on a Permeable Plate in a Supersonic Flow with a Positive Pressure Gradient under Foreign Gas Injection

A Turbulent Boundary Layer on a Permeable Plate in a Supersonic Flow with a Positive Pressure Gradient under Foreign Gas Injection

Velocity spectra and scale decomposition of adverse pressure gradient turbulent boundary layers considering history effects

Experiments at relatively large Reynolds number were conducted to better understand the influence of an adverse pressure gradient on the turbulence in two-dimensional boundary layer flows. One focus is on documenting the scale contributions to the Reynolds normal and shear stress profiles under the influence of a positive streamwise pressure gradient. Toward these aims, velocity spectra at friction Reynolds numbers (7100≤Reτ≤8600) are presented, analyzed, and compared to a zero pressure gradient case from the same facility at nominally matching Reynolds number. Distance-from-the-wall scaling is central to numerous theoretical and modeling considerations of the canonical flat plate flow. Consistently, the present spectral measurements reveal clear evidence for its preservation on the inertial sublayer under modest adverse pressure gradients. Increases are seen in the viscous-scaled premultiplied spectra in the outer region as the pressure gradient increases — commensurate with the increases observed in the outer peaks of the streamwise and wall-normal velocity variances, as well as the Reynolds shear stress. Effects of varying Reτ on the streamwise and wall-normal velocity variances and the Reynolds shear stress are studied by comparing the present data at varying Clauser pressure gradient parameter, β, with previous experiments having similarly varying β at significantly lower Reτ (≈1900). This allows to study the effects of changing Reynolds number at matched β. Cases at similar β and Reynolds number, but with varying flow history are also examined, wherein the same β value is arrived either by starting from a smaller or larger initial β. The effects of β>0 on the large and small scale motions are investigated by segregating the signal contributions according to a cut-off wavelength established in previous zero pressure gradient flows. Under a normalization that uses a hybrid velocity scale this analysis reveals similarity between the outer regions of the spectrally-decomposed variances and Reynolds shear stress. These analyses also reveal a more dramatic reduction in the near-wall large scale contribution to the Reynolds shear stress gradient in the β>0 flow when compared to the β=0 flow.

TURBULENT BOUNDARY LAYER ON A PERMEABLE PLATE IN SUPERSONIC FLOW WITH POSITIVE PRESSURE GRADIENT UNDER FOREIGN GAS INJECTION

A numerical simulation of a turbulent boundary layer on a permeable plate with helium injection into a supersonic xenon flow in the presence of a positive longitudinal pressure gradient has been carried out. The injection regimes are considered, in which the temperature of the injected gas is lower than the temperature of the adiabatic impermeable wall and the stagnation temperature of the oncoming flow. The existence of a minimum temperature of the permeable wall is confirmed, at which the wall temperature is lower than the temperature of the injected gas, while there are two sections along the length of the permeable plate in which the adiabatic conditions are satisfied. The results of calculations of a supersonic flow with a longitudinal pressure gradient differ significantly from the results obtained for a gradientless flow around a plate, both for subcritical and critical injection.

Synergistic effects of vapor and gaseous cavitation and mass-transfer mechanism in a mechanical pump

Dynamic gas–liquid mass-transfer processes are extensively encountered in gas–liquid mixture transport systems, where mechanical pumps pressurize the mixture and are accompanied by flow and mass-transfer instabilities. Herein, our proposed gaseous cavitation model was innovatively developed to revolutionize the independent unidirectional absorbed or evolved mass transfers. Complex gas–liquid behaviors under the synergetic effects of gaseous and vapor cavitations were achieved for the first time in an on-orbit refueling mechanical pump. Four coupled mass-transfer processes, namely, evolution, evaporation, absorption, condensation, and gas–liquid distribution, were investigated through numerical calculations. The results indicated that when the solution was close to critical saturation and conversion of the mass-transfer direction, a surge in the mass-transfer rate, and more intense hydrodynamic instability occurred. The vapor drove the accumulation of the evolved gas along the edge of the vapor in the impeller, where the evolved-dominated mass-transfer bands existed on the suction surfaces of the long blade, exhibiting the degassing characteristics of the vapor cavity, and other regions belonged to absorption-dominated region. Continuous dissolution induced by significant positive pressure gradient led to the maximum absorbed oxygen concentration at the impeller outlet. The maximal increments of absorbed oxygen in the suction chamber, impeller, and volute were 98%, 447%, and 694%, respectively, and the volume fractions were attenuated by 18.3%, 12.5%, and 5.0%, respectively. Notably, an increase in the gas volume fraction was the dominant reason for exacerbating the instability of the impeller forces, and the range of the radial force tended to be narrow and concentrated as the concentration increased.

Theoretical study on solute migration and band broadening occurring in pressure-enhanced liquid chromatography

Upon recently studying the use of pressure gradients during liquid chromatography (LC), it was noted that pressure differentials across a column can have a significant impact on peak shape, not just retention as has been noted several times before. Theoretical models and thought experiments were performed here to more carefully study these effects. Two situations have been elucidated. The first is one that reflects a protein reversed phase separation wherein solute retention increases with pressure. In this condition, it has been found that a positive pressure gradient will result in band broadening while a negative pressure gradient will help yield sharper peaks. The second case that has come to be better appreciated is when solute retention decreases with pressure, which can occur in protein ion exchange (IEX) and hydrophobic interaction chromatography (HIC). In this situation, a positive pressure gradient will conversely result in peak sharpening, and a negative pressure gradient will introduce band broadening. These observations have facilitated making new fundamental understandings on pressurized separations which has in turn made it possible to begin envisioning new ways of and reasons for applying pressure enhanced LC methods.

Tectonic deformation at the outer rise of subduction zones

SUMMARY Fluids associated with subducting slabs play a crucial role in regulating the dynamics of water discharge, subsequent arc magmatism and intermediate-depth earthquakes in subduction zones. The incoming slab mantle hydration is primarily determined by deep normal faulting due to plate bending at the trench. However, the controlling factors on the outer rise faulting pattern, and the correlation between the inherited outer rise deformation and the intermediate-depth earthquakes, remain to be understood. Here we present high-resolution viscoelasto-plastic numerical models of free subduction for slab bending-related faulting prior to subduction. Our model results show that plastic weakening and friction coefficient of the slab mantle exhibit a significant impact on fault pattern, while plate age and elasticity have a minimal bearing for mature slabs. The brittle bending faults result in large positive pressure gradients in the vertical direction, facilitating seawater infiltrating into the subducting slabs, which corroborates previous numerical models. The faults reaching 15–30 km beneath the Moho coincide with the width of the double seismic zone in subduction zones. We anticipate that water pumped into the slab mantle along the faults, with decreasing water content along the depth, can explain the relatively sporadic lower plane earthquakes.

Modeling of Turbulent Heat-Transfer Augmentation in Gas-Droplet Non-Boiling Flow in Diverging and Converging Axisymmetric Ducts with Sudden Expansion

The effect of positive (adverse) and negative (favorable) longitudinal pressure gradients on the structure and heat transfer of gas-droplet (air and water) flow in axisymmetric duct with sudden expansion are examined. The superimposed pressure gradient has a large influence on the flow structure and heat transfer in a two-phase mist flow in both a confuser and a diffuser. A narrowing of the confuser angle leads to significant suppression of flow turbulence (more than four times that of the gas-drop flow after sudden pipe expansion without a pressure gradient at φ = 0°). Recirculation zone length decreases significantly compared to the gas-droplet flow without a longitudinal pressure gradient (by up to 30%), and the locus of the heat-transfer maximum shifts slightly downstream, and roughly aligns with the reattachment point of the two-phase flow. Growth of the diffuser opening angle leads to additional production of kinetic energy of gas flow turbulence (almost twice as much as gas-droplet flow after a sudden pipe expansion at φ = 0°). The length of the flow recirculating region in the diffuser increases significantly compared to the separated gas-droplet flow without a pressure gradient (φ = 0°), and the location of maximum heat transfer shifts downstream in the diffuser.

Mechanism study of flow characteristics on small HAWT blade surfaces based on airfoil concavity under yaw conditions

Aiming to solve the power output reduction caused by the flow separation, this study applied a passive flow control method on blade suction surfaces of a small horizontal axis wind turbine. An airfoil with a semi-elliptical concavity was introduced, and several concave blades were, thus, designed. Among them, the blade with a concavity located at 80% chord and a length of 350 mm was selected for further analysis according to the aerodynamic performance. As a result, it has been found that the concave airfoil had better performance at high wind speeds, low rotational speeds, and small yaw angles, especially the positive yaw conditions. The flow field mechanism could be interpreted with a positive pressure gradient generated by the airfoil concavity. Under the positive yaw angle of 10°, the concavity effect resulted in a greater aerodynamic lift. The azimuth angle of 0° shows an obvious control effect at the blade tip. On the contrary, the concavity has little effect at an azimuth angle of 120° near the leading-edge. At the azimuth angle of 240°, a significant concavity effect at the blade root could be found, while the aerodynamic benefits were not as remarkable as an azimuth angle of 0° in the vicinity of the blade tip. Aside from that, when the flow separation was serious due to the three-dimensional rotational effect, the concavity has no distinct effect on separation control. In essence, the airfoil concavity had a favorable impact on flow separation control and effectively enhanced the power output of the wind turbine.

Magnetofluid unsteady electroosmotic flow of Jeffrey fluid at high zeta potential in parallel microchannels

Abstract In this article, the magnetofluid unsteady electroosmotic flow (EOF) of Jeffrey fluid with high zeta potential is studied by using the Chebyshev spectral method and the finite difference method. By comparing the potential distribution and velocity distribution obtained by the Chebyshev spectral method and finite difference method, it is concluded that the Chebyshev spectral method has higher precision and less computation. Then the numerical solution obtained by the Chebyshev spectral method is used to analyze the flow characteristics of Jeffrey fluid at high zeta potential. The results show that the velocity of Jeffrey fluid increases with the increase of the wall zeta potential and electric field intensity. The oscillation amplitude of velocity distribution increases with the increase of relaxation time, but decreases with the increase of retardation time. With the increase of Hartmann number, the velocity first increases and then decreases. The positive pressure gradient promotes the flow of fluid, and the reverse pressure gradient impedes the flow of fluid.