The internal flow in a vertical axial-flow pump is a complex unsteady three-dimensional viscous flow. An unstable flow often produces complex flow phenomena such as flow separation, vortices, and secondary reflux, which reduces the operating efficien...
Long-distance free-surface water-conveyance tunnels require a spatially continuous representation of transient water depth, yet in practice flow is monitored at only a few sections. This study develops a physics-informed neural network (PINN) that re...
For the control of the outlet flow rate of a constant-flow water-saving device under different water pressures, this study developed and implemented a custom User-Defined Function (UDF) program to simulate the dynamic motion of the water-saving valve...
The tilt-rotor unmanned aerial vehicle (TRUAV) is characterized by both multi-rotor vertical takeoff or landing and fixed-wing long-duration flight. Not only the structure of TRUAV is complex, but also the aerodynamic coupling is severe. Especially w...
Steady-state and transient hydraulic characteristics of a novel three-plate vertical rotary gate were analysed through physical model experiments and numerical simulations. An experimental gate system was built to analyse the flow characteristics of...
Submerged entry nozzle (SEN) clogging will affect the production efficiency and product quality in the continuous casting process. In this work, the transient SEN clogging model is developed by coupling the porous media model defined by the user-defi...
Pressure relief valves (PRVs) are key safety components in power transformers, and their discharge performance directly influences pressure mitigation during internal fault events. This study presents a density-based topology optimization approach to...
In ultra-cold narrow-window drilling, pipe connection causes flow-path switching as the main circulation is interrupted and bypass circulation is established, breaking the initial relative pressure balance of the whole wellbore and inducing asymmetri...
In order to predict the fluid–structure coupling performance of a full-scale composite propeller under a wake flow field behind a full ship, a bidirectional transient fluid–structure coupling algorithm was established. The performance inc...
The transient mechanism of dual-boundary dynamic opening in the inlet during stage transition of an integral solid rocket ramjet (ISRR) remains insufficiently understood. To address this issue, a combined approach involving numerical simulations and...
The double-piece inner ring ball bearing is an important part of an aero-engine. An excessive bearing temperature leads to bearing thermal expansion, lubricating oil performance degradation, and other problems that seriously affect the service life a...
Convective Marangoni instabilities in drying polymer films may induce surface deformations, which persist in the dry film, deteriorating product performance. While theoretic stability analyses are abundantly available, experimental data are scarce. W...
Reliable wellbore cleaning remains difficult in deviated, horizontal, extended-reach, deep, and ultra-deep wells because the downhole distribution and mechanical state of cuttings beds cannot usually be observed directly. This review examines cutting...
The accurate reconstruction and real-time prediction of transient three-dimensional flow fields in hydraulic turbines are critical for ensuring operational stability under renewable energy-driven variable-load conditions, yet conventional computation...
Friction pairs in wet clutches operate under complex conditions, which can cause surface damage and reduce overall clutch reliability. Surface texturing is an established technique for improving the tribological performance of such mechanical interfa...
In order to study the influence of regulating valve openings on the dynamic characteristics of the rotor structure of a multistage pump during the transient startup process, a seven-stage pump was selected as the research object. The transient startu...
In oil and gas exploitation, the multiphase pump is a vital piece of equipment to guarantee production with high efficiency and stable operation. The complicated pattern of multiphase flow in the multiphase pump affects the pump performance; for this...
On one hand, a blowout test can clean the bottom of the well, and on the other, it can learn the productivity of the well, which is important work before putting the well into production and also the main basis for production allocation of the well....
To study the coupling mechanism between droplet evaporation characteristics and flame propagation, in this paper, the ignition process in a single dome lean direct injection combustor is simulated by the Large Eddy Simulation (LES) method. A new conc...
This paper presents the experimental results of separation and reattachment transient flow processes over a NACA0015 airfoil wing when using a plasma actuator for flow control. In addition, it addresses the flow behavior in the transient processes wh...
The working condition of a centrifugal pump as a turbine (PAT) is often unsteady. The rotating speed of a PAT constantly varies as the flow and load change, resulting in transient hydrodynamic behaviors between different working conditions. During th...
Siphon vertical axial-flow pump systems are widely used in large-scale low-head pumping stations, irrigation and drainage projects, urban flood control, and water diversion engineering, where safe and stable operation is essential for hydraulic syste...
Exact solutions of the Navier–Stokes equations are derived for three startup flows in a right-angled isosceles triangular channel: Couette flow driven by impulsive motion of the hypotenuse, Couette flow driven by impulsive motion of one leg, an...
Transient processes that occur in pumped storage power plants can cause high-pressure conditions, which in turn can result in vibrations in the pump–turbine structure and even damage to structural components. It is therefore crucial to research...
Understanding the transient properties of cementitious pastes is crucial for construction materials engineering. Computational modeling, particularly through Computational Fluid Dynamics (CFD), offers a promising avenue to enhance our understanding o...
An experimental investigation was performed on the wake flow field of an isolated roughness element of a flat plate at Mach 6 by employing the nanoparticle-based planar laser scattering (NPLS) approach. The three-dimensional features and causes of th...
This paper investigates the transient flow rate performance of small piezoelectric-hydraulic pumps. In a previous study, a small piezoelectric hydraulic pump was designed and developed to be applicable to the braking systems of small- and medium-size...
Making rate transient analysis (RTA) and formation evaluation for multi-fractured tight gas wells has always been a difficult problem. This is because the fluid flow in the formation has multiple nonlinear flow mechanisms, including gas-water two-pha...
Digital transformation has become one of the major themes of the development of the global oil industry today. With the development of digital transformation, on-site production will surely achieve further automated management, that is, on-site produ...
The brake–release stability of electro-hydraulic thrusters (EHTs) significantly affects the safety of hydraulic braking systems, especially under low-temperature conditions with varying fluid viscosity. Most existing studies have focused on mac...
In this paper, a computational fluid dynamics (CFD) simulation method based on the polyhedral nested grid is developed. By comparing the simulation and test results of the hovering flow field of the Caradonna–Tung rotor, the forward flight flow...
Transient flows represent a critical topic in the field of hydraulic engineering, one that has witnessed significant progress in recent decades [...]
In hydraulic systems, transient flow often occurs and may results in cavitation in pipelines. In this paper, the Computational Fluid Dynamics (CFD) method based on the Fluent software was used to investigate the cavitation flow in pipeline; the densi...
The purpose of this paper is to study the mechanism and improve the prediction accuracy of transient torque converter cavitation flow by the application of scale-resolving simulation (SRS) methods with particular focus on cavitation vortex flow. Firs...
With the rapid development of computational fluid dynamics (CFD) technology, it has been widely used to study the wind field characteristics of downbursts in mountainous areas. However, there is little guidance on the selection of different turbulenc...
Our recent knowledge about the role of different fluid driving forces in the response of groundwater flow systems to climate change is still limited. This current study aimed to evaluate possible spatial and temporal changes in complex, gravity- and...
Many researchers have investigated the impact factors of the bath–metal flow in an aluminum reduction cell using the simulation method. However, only a few have coupled their models with transient electromagnetic force, which makes the model cl...
Low specific speed centrifugal pumps are widely used in urban water supply, agricultural irrigation, petrochemical and other fields due to their small flow rate and high head. Therefore, the study of unsteady flow characteristics plays a vital role i...
The open-source software OpenFOAM 5.0 was used as a platform to perform steady-state and transient numerical simulation for full flow field of a pipeline centrifugal pump (specific speed ns = 65) in a wide operating capacity range of 0.3Qd~1.4Qd. The...
The transient characteristic of the power-off process is investigated due to its close relation to hydraulic facilities’ safety in a pumped storage hydropower (PSH). In this paper, power-off transient characteristics of a PSH station in pump mo...
The aim of this study was to investigate the action mechanism of the rotor–stator interaction (RSI) on the transient flow field and hydrodynamic noise field inside the impeller of jet centrifugal pumps (JCPs) and optimize effects of the guide v...
Modulated laser absorption spectroscopy is an ideal technique for evaluating flow-field parameters and determining flow-field quality by measuring the atoms dissociated in high-temperature environments. However, to obtain the absolute number density...
The Ladle Shroud has become an important part of secondary steelmaking, with its role in reducing liquid steel contamination and process improvements. Due to the inherent negative pressure at the lower nozzle–Ladle Shroud joint, it is well know...
Wind tunnel experiments were performed to investigate the response of a wind turbine model immersed in a replicated atmospheric boundary layer to dynamic changes in the yaw angle. Both the flow field in the wake and the operating properties of the tu...
As a core safety component in the hydraulic system of CNC stretching pads, the safety locking valve undertakes precise stamping position maintenance and emergency braking protection; its performance dictates the hydraulic system’s operational s...
As unitised regenerative proton exchange membrane fuel cell (URPEMFC) is progressing in terms of its performance, more emphasis should be placed on the understanding of the interaction between multiphase reactants and products and its effect during t...
This study investigates the transient behavior of a single-blade centrifugal pump under variable frequency speed regulation, with the objective of enhancing both pump efficiency and operational stability under variable frequency conditions. By integr...
In long-distance natural gas transmission, installing an axial flow check valve at the compressor outlet of a compressor station helps prevent backflow. Failure of this valve can cause compressor reverse rotation, which disrupts gas delivery. This st...
A computational fluid dynamics simulation was developed for the growth zone of gallium nitride crystallized using the alkaline ammonothermal method, considering the geometry of the seed crystals and the installation setup. The model focuses on temper...
Fault detection in subsea pipelines is a difficult problem for several reasons, and one of the most important is the inaccessibility of the system. This criticality can be overcome by using transient test-based techniques. Such an approach is based o...
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