Qingfeng Xia

United Kingdom Atomic Energy Authority, CCFE

Spontaneous imbibition in porous media plays an important role in numerous industrial processes, but its underlying mechanisms are still poorly understood due to the complicated structure and multiple surface properties of natural porous media. In order to fill this gap, a quasi-three-dimensional color-gradient lattice Boltzmann model is applied to...

Higher cutting speeds are desired for an enhanced manufacturing productivity. However, this is limited by the increased wear rate at the elevated cutter-chip interface temperature. To achieve the optimal cutting speed and cutter design for a prolonged tool life, a high fidelity thermal model is indispensable. In this paper, the thermal distribution...

The heat transfer performance and friction loss of two-pass ribbed channels are highly influenced by the combined effect of rib orientation and bend shape. This paper, for the first time, numerically investigates this effect for four rib orientations, two rib angles and eight different bend shapes at Reynolds number of 30,000. The results show that...

Prediction of contact temperature between two materials in high speed rubbing contact is essential to model wear during unlubricated contact. Conventionally assumptions of either steady or an annular heat sources are used for slow and high speed rottion respectively. In this paper, a rotating heating source is solved using an in-house finite elemen...

Prediction of the contact temperature between two materials in high speed rubbing contact is essential when analysing the wear mechanism and modelling wear rate for unlubricated contact. Conventionally the assumptions used for a pin-on-disc configuration are either a steady heat source at the contact for slow speed rotation or an annular source alo...

A trend of tight integration of Computer-aided Design (CAD) and Computer-aided Engineering (CAE) has been seen for commercial and open source software packages. CAD platforms extend their functions from geometry creation to engineering simulation and product life management, while CAE software, for physical system simulation in a narrow sense, has...

Transient gap or crack width monitoring is essential for structural health monitoring and failure analysis of large civil structures. In this paper, an innovative multi-axis displacement sensor, which utilises metal foil strain gauges on a strain shunt structure, has been proposed. This displacement sensor has the advantages inherited from metal fo...

FEM solver for multibody, multiphysics, multiscale and reduced-order nonlinear problems. source code can be found: https://github.com/qingfengxia/FenicsSolver

Strong secondary flow generated by ribbed channel and U-shaped bend is the key for forced convection performance and energy dissipation in U-shaped cooling passage. This investigation studies the coupling of nine different rib orientation and the 180-degree bend on overall friction loss and forced convection in the U-shaped passage by ANSYS CFX com...

Flow and heat transfer characteristics of mist/steam cooling and mist/air cooling in a square channel with 60º rib angle are numerically investigated for a wide range of operating parameters, such as Reynolds number ranging from 10000 to 60000, reference pressure from 0.1 MPa to 0.5 MPa and inlet temperature from 120 °C to 200 °C. Also, the heat tr...

This module aim to accelerate CFD case build up for OpenFOAM, with non-stop geometry modeling, one-click meshing and GUI for boundary setting.

Cost-effective and energy-saving sensor for large dynamic strain measurement is still lacking for wireless sensor networking application. In this paper, a shunt structure is proposed to measure large dynamic strain using metal foil strain gauge without fatigue failure. This shunt structure is made of single metal sheet for convenient installation....

In this paper, mixing between two liquid streams of the same flow rate in a planar mixing channel enhanced by means of three lateral synthetic jet pairs is examined using PLIF and PIV at net flow Reynolds numbers of Ren =2, 10 and 83. The changes in the flow Reynolds numbers are produced with the use of fluids with different dynamic viscosities. Th...

Battery-powered wireless sensor networks have been extensively deployed in condition monitoring and structural health monitoring systems, but the performance of wireless sensors are limited by battery capacity and difficulty of application in rotating machines. In this paper, a variety of commercial wireless charging solutions and coil-shaft config...

In order to eliminate the fatigue failure of metallic thin film strain gauges under large alternating strain condition, a mechanical structure reducing the large strain on the target surface proportionally to a safe level is proposed as strain shunt in this study. The working principles of the strain shunt structure are illustrated and the shunt ra...

In this paper, the flow patterns of circular synthetic jets issuing into a quiescent flow at low Reynolds numbers are studied numerically. The results confirm the presence of the three jet flow regimes, i.e. no jet formation, jet flow without rollup and jet flow with rollup reported in the literature. The boundaries of the different jet flow regime...

In this paper, mixing in microscale channels augmented by vibrating stirs is numerically studied. The micro-mixer comprises of several micro stirs (μ-stirs) placed in the microscale channel. Chaotic advection appears for the fact that the incoming flow interplays with the μ-stirs transversely moving between two sidewalls. A two-dimensional numerica...

In the work reported in this paper, laminar flow mixing between two parallel water streams, which are injected into a rectangular channel at a net flow Reynolds number of 83, is enhanced using a pair of staggered lateral synthetic jets (LSJ) located on the opposite walls of the mixing channel. The synthetic jet pair is operated 180° out-of-phase at...

In this paper, the effect of three synthetic jet pairs on the mixing between two fluid streams in a planar mixing channel is examined at a net How Reynolds number of 2. They are mounted transversely to the incoming flow and operated 180 degrees out The PLIF technique is used to provide a visual impression of the effect of synthetic jets on mixing a...

In this paper, mixing between two fluid streams, which are injected into a planar mixing channel via a Y-shaped confluence section at the same volume flow rate, is studied experimentally. The injection of the two fluid streams is controlled by two separate solenoid valves, which are operated with a phase difference of 180°, using pulse width modula...

In the work presented in this article, the behaviour of circular synthetic jets issuing into quiescent surrounding fluid at low Reynolds numbers is experimentally studied for potential mixing applications of synthetic jets at micro-scales or in highly viscous fluids. Sugar solutions and silicone oil are used as the flow media in order to achieve th...

In this paper, enhancement of mixing between two water streams of the same flow rate in a planar channel by means of a lateral synthetic jet pair is studied at a net flow Reynolds number of 83 using PLIF and PIV. The synthetic jet pair is operated 180° out-of-phase at a range of actuation frequencies and displacements, with the latter being charact...

In this paper, mixing between the fluid from a primary planar jet and two surrounding secondary planar jets which are pulsated out-of-phase is studied experimentally. Solenoid values are used to control the flow injection into the mixing channel with pulse-width modulation. The experiments are conducted using water at a range of pulsation frequency...