Lin Xu

Dr. Lin Xu

orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 May 2021 in IEEE Transactions on Circuits and Systems II: Express Briefs
Verified
Journal Article
Closed access
LXLin Xu
Lin Xu
WYWei Yu
Wei Yu
WQWei Qin
Wei Qin
JCJian-Xin Chen
Jian-Xin Chen
In this brief, the design approach of dual-channel filter based on dual-mode dielectric resonator (DR) is proposed. A pair of orthogonal modes in dual-mode DR with the same and different frequencies are analyzed and applied to construct the two channel filtering responses independently. Meanwhile, the isolation between the two channels can be realized due to the orthogonality between the modes. Thus, the design process is simple and efficient. To verify the design approach, two prototypes with the same and different frequencies are designed. Meanwhile, the $3^{rd}$ -order dual-channel filter with different frequencies are also implemented and measured. The frequencies of the two designs are 1.54GHz and 1.53/1.68GHz, respectively. In each design, the return losses of the two channels are better than 14dB, the insertion losses are less than 0.68dB, and the band isolation is greater than 20dB. Meanwhile, the results also show that arbitrary filtering order and high design flexibility can be achieved.


23 December 2022 in Processes
Verified
Journal Article
Open access
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LXLin Xu
Lin Xu
QPQun-Wu Pei
Qun-Wu Pei
HZHan Zefeng
Han Zefeng
JCJie Cui
Jie Cui
HPHonggang PAN
Honggang PAN
YYYantao Yao
Yantao Yao
Electromagnetic braking (EMBr) technology, as one of the most effective technologies in the continuous casting process, provides an effective tool for improving the internal and external defects of steel products. Specifically, the EMBr technology takes the benefit of the generation of Lorentz force to decrease flow instability, mold powder entrapment, and surface defects, if applied properly. For this purpose, to gain a clear understanding of the effect of EMBr technology on the continuous casting process, a commonly used EMBr technology, namely ruler EMBr technology, is applied in the current work to investigate the dynamic behaviors of molten steel flow and steel–slag interface fluctuation inside a slab mold. Furthermore, to obtain a desirable braking effect of the ruler EMBr technology, operational parameters including the magnetic flux density, submerged entry nozzle (SEN) depth, and magnetic pole location are numerically investigated. The results demonstrate that the braking effect exerted by the ruler EMBr device is favorable for suppressing the impact of upward stream on the steel–slag interface with the magnetic flux density exceeding 0.3 T. For the influence of the SEN depth and magnetic pole location on the effect of ruler EMBr mold, the results show that a steady jet flow pattern can be obtained through the adjustment of a location between the ruler EMBr device and the SEN depth. For instance, when the ruler EMBr device installation position of 225 mm corresponds to the SEN depth of 150 mm, the upward deflection of jet stream is suppressed and a stable interface fluctuation profile is formed. With this adjustment, the possibility of mold flux entrapment is decreased.

18 April 2023 in Metallurgical Research & Technology
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Journal Article
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LXLin Xu
Lin Xu
QPQunwu Pei
Qunwu Pei
ZHZefeng Han
Zefeng Han
EWEngang Wang
Engang Wang
JWJianyu Wang
Jianyu Wang
CKChristian Karcher
Christian Karcher
During continuous casting process, the internal molten steel flow pattern of the mold is one of the important factors affecting the quality of slab products. The application of electromagnetic braking (EMBr) technology in the slab caster provides an effective solution to improve the molten steel flow pattern in the mold. In the current research, one of the commonly used EMBr technology is studied, namely the Ruler-EMBr technology. In detail, the effect of magnetic flux density on the behavior of the molten steel jet flow, heat transfer, and solidification in a 1450 mm × 230 mm slab mold is numerically simulated through a Reynolds-averaged Navier-Stokes (RANS) turbulence model together with an enthalpy-porosity approach. The simulation results indicate that the electromagnetic force generated by the Ruler-EMBr can significantly suppress the diffusion of the impinging jet to the narrow face of the mold with the increase of magnetic flux density. By that, the impact of the upward backflow on the meniscus region in the mold is suppressed. Correspondingly, the uniformity of the temperature distribution in the mold is effectively improved. The parametric studies suggest that the optimized magnetic flux density is 0.3 T to ensure the improvement of steel quality with a casting speed of 1.6 m/min. By applying the magnetic flux density of 0.3 T, the Ruler-EMBr has a better capability to reduce the maximum amplitude of the surface velocity by 24.5% and increase the average surface temperature of the molten steel by 0.25% when compared to the case of No-EMBr. With this electromagnetic parameter, the Ruler-EMBr technology can well prevent the mold flux entrapment and promote solidified shell uniform growth along the casting direction.

23 November 2022 in Symmetry
Verified
Journal Article
Open access
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Shuo YangShuo Yang
Shuo Yang
DQDaocheng Qin
Daocheng Qin
YZYupeng Zhang
Yupeng Zhang
LXLin Xu
Lin Xu
YFYudong Fu
Yudong Fu
HPHonggang PAN
Honggang PAN
This paper investigated the influence of surface internal energy instability caused by the gravitational tilt angle on solutocapillary convection. The results showed that the spatio-temporal evolution of solutocapillary convection in a non-axisymmetric liquid bridge was divided into three stages under different gravitational tilt angles, “the initiating stage near the upper corner”, “development to the intermediate height”, and “shrinking toward the bottom corner”. The non-equilibrium of the left or right interface curvature caused by internal energy instability promotes the distortion of the cell flow structure. The concentration gradient on the far-earth side increases first, due to the gravitational tilt angle. With the increasing gravitational tilt angle, the lateral extension of the cell flow is inhibited. The transverse/longitudinal velocity components are suppressed; however, the velocity gradient near the boundary is increased, and the uniformity of the velocity distribution in the center of the liquid bridge is improved. The axial component of the Bond number decreases in a small range (Bo′ = 1→0.98) with the internal energy instability, however, which has a significant effect on surface flow. Therefore, in the initiation and development stages of solutocapillary convection, the decay rate of the Marangoni number respectively decreases and increases with the increasing Bond number. The axial component of the Bond number decreases in a small range with the internal energy instability, which has a significant effect on the solute Marangoni number (Mac). In the initiation stage of solutocapillary convection, the decay rate of the Mac decreases with the increasing Bond number. Its change law is the opposite in the development stage of solutocapillary convection.

23 May 2024 in Metallurgical Research & Technology
Verified
Journal Article
Closed access
PDF file
LXLin Xu
Lin Xu
MTMeiling Tang
Meiling Tang
ZLZe Lyu
Ze Lyu
NLNan Li
Nan Li
CLCong Liu
Cong Liu
QPQunwu Pei
Qunwu Pei
Electro-magnetic brake (EMBr), as a necessary technique to adjust the metal flow within the mould, has been extensively applied in the continuous casting (CC) production. The EMBr technique, if appropriately applied, can take the benefit of braking effect to weaken jet impingement effect, suppress fluid disturbance and stabilize surface fluctuation. As a result, to obtain a reasonable flow pattern within the CC mould, the braking performance of EMBr technique needs to be flexibly adjusted according to the variation of operational parameters. In this article, to obtain a braking performance of a commonly used EMBr-single-ruler technique within an optimal range, the effect of operating parameters on the metal liquid flow and thermal characteristics in a compact strip production (CSP) thin slab mould is described through a 3-D mathematical modeling of multi-physical field coupling. The results illustrate that the braking performance of the EMBr-single-ruler device is weakened with the increase of the casting speed or the mould width. For the effect of the casting speed and mould width on the metal flow with the application of an EMBr device, an optimum braking performance of the EMBr-single-ruler device can be obtained under the matching parameters of a magnetic induction intensity of 0.30 T and a casting speed of 4.5 m ∙ min‒1 together with a mould width of 1500 mm. Relative to the absence of the EMBr-single-ruler device, the maximum surface fluctuation height is controlled at 6.2 mm, and the mean surface temperature is raised to 1803.6 K. Based on these findings, we conclude that the proper utilization of the EMBr-single-ruler device can avoid the entrainment of flux powder and improve the melting performance of flux powder.