Field measurement and numerical simulation of snow deposition on an embankment in snowdrift

Wenyong Ma,Feiqiang Li,Yuanchun Sun,Jianglong Li,Xuanyi Zhou 한국풍공학회 2021 Wind and Structures, An International Journal (WAS Vol.32 No.5

Snow accumulation on the road frequently induces a big traffic problem in the cold snowy region. Accurate prediction on snow distribution is fundamental for solving drifting snow disasters on roads. The present study adopts the transient method to simulate the wind-induced snow distribution on embankment based on the mixture multiphase model and dynamic mesh technique. The simulation and field measurement are compared to confirm the applicability of the simulation. Furthermore, the process of snow accumulation is revealed. The effects of friction velocity and snow concentration on snow accumulation are analyzed to clarify its mechanism. The results show that the simulation agrees well with the field measurement in trends. Moreover, the snow accumulation on the embankment can be approximately divided into three stages with time, the snow firstly deposited on the windward side, then, accumulation occurs on the leeward side which induced by the wake vortex, finally, the snow distribution reaches an equilibrium state with the slope of approximately 7°. The friction velocity and duration have a significant influence on the snow accumulation, and the vortex scale directly affected the snow deposition range on the embankment leeward side.

Proteomic and Morphologic Evidence for Taurine-5-Bromosalicylaldehyde Schiff Base as an Efficient Anti-Mycobacterial Drug

( Wenyong Ding ),( Houli Zhang ),( Yuefei Xu ),( Li Ma ),( Wenli Zhang ) 한국미생물생명공학회(구 한국산업미생물학회) 2019 Journal of microbiology and biotechnology Vol.29 No.8

Mycobacterium tuberculosis, a causative pathogen of tuberculosis (TB), still threatens human health worldwide. To find a novel drug to eradicate this pathogen, we tested taurine-5- bromosalicylaldehyde Schiff base (TBSSB) as an innovative anti-mycobacterial drug using Mycobacterium smegmatis as a surrogate model for M. tuberculosis. We investigated the antimicrobial activity of TBSSB against M. smegmatis by plotting growth curves, examined the effect of TBSSB on biofilm formation, observed morphological changes by scanning electron microscopy and transmission electron microscopy, and detected differentially expressed proteins using two-dimensional gel electrophoresis coupled with mass spectrometry. TBSSB inhibited mycobacterial growth and biofilm formation, altered cell ultrastructure and intracellular content, and inhibited cell division. Furthermore, M. smegmatis adapted itself to TBSSB inhibition by regulating the metabolic pathways and enzymatic activities of the identified proteins. NDMA-dependent methanol dehydrogenase, NAD(P)H nitroreductase, and amidohydrolase AmiB1 appear to be pivotal factors to regulate the M. smegmatis survival under TBSSB. Our dataset reinforced the idea that Schiff base-taurine compounds have the potential to be developed as novel anti-mycobacterial drugs.

Experimental Evaluation on Shape and Control of Chip in Milling of PE WPC

Shi Wenyong,Ma Yan,Wu Zhe,Yang Chunmei 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.7

This paper the regular patterns of chip flow, chip curler radius and thickness under different cutting parameters when processing PE WPC with different wood flour contents under the condition of up milling and down milling. Compared with up milling, down milling has greater impact on chip flow direction and cutting speed. However, there are more dust-shaped chips in the up milling. In the down milling, chip curler has less change with cutting parameters. Only when the feed speed is 14m/min or the cutting speed is 1800m/min, the chip curl radius is larger. The chip thickness increases when the feed speed or the cutting width increases and decreases when the cutting speed increases.

Research on Cutting Force and Cutting Vibration in Milling of PE WPC

Shi Wenyong,Ma Yan,Yang Chunmei 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.10

This paper presents the impact of the change of cutting parameters on cutting force and cutting vibration by the milling experiment of PE WPC. In the text, 60% wood flour content and 70% wood flour content WPC are compared in up milling and down milling. The result shows that cutting force shows a progressive increasing trend as the feed speed increasing. The cutting force in up milling is totally smaller than in down milling with the change of cutting speed. Cutting force shows an increasing trend with the cutting width increasing. The impact of feed speed on cutting vibration is more obvious. The cutting vibration of 60% wood flour content is more susceptible than 70% wood flour content. In the cutting speed experiment, the cutting vibration in up milling is obviously bigger than in down milling. The cutting vibration of 60% and 70% wood flour content is almost the same in down milling. However, it is opposite in up milling. The cutting vibration shows a progressive increasing trend in down milling and steady in up milling as the cutting width increases.

Coupling effects of vortex-induced vibration for a square cylinder at various angles of attack

Deqian Zheng,Wenyong Ma,Xiaobin Zhang,Wei Chen,Junhao Wu 한국풍공학회 2022 Wind and Structures, An International Journal (WAS Vol.34 No.5

Vortex-induced vibration (VIV) is a significant concern when designing slender structures with square cross sections. VIV strongly depends on structural dynamics and flow states, which depend on the conditions of the approaching flow and shape of a structure. Therefore, the effects of the angle of attack on the coupling effects of VIV for a square cylinder are expected to be significant in practice. In this study, the aerodynamic forces for a fixed and elastically mounted square cylinder were measured using wind pressure tests. Aerodynamic forces on the stationary cylinder are firstly discussed by comparisons of variation of statistical aerodynamic force and wind pressure coefficient with wind angle of attack. The coupling effect between the aerodynamic forces and the motion of the oscillating square cylinder by VIV is subsequently investigated in detail at typical wind angels of attack with occurrence of three typical flow regimes, i.e., leading-edge separation, separation bubble (reattachment), and attached flow. The coupling effect are illustrated by discussing the onset of VIV, characteristics of aerodynamic forces during VIV, and interaction between motion and aerodynamic forces. The results demonstrate that flow states can be classified based on final separation points or the occurrence of reattachment. These states significantly influence coupling effects of the oscillating cylinder. Vibration enhances vortex shedding, which creates strong fluctuations in aerodynamic forces. However, differences in the lock-in range, aerodynamic force, and interaction process for angles of attack smaller and larger than the critical angle of attack revealed noteworthy characteristics in the VIV of a square cylinder.

Numerical investigation on pressure responsiveness properties of the skirt-cushion system of an air cushion vehicle

Xu, Shengjie,Tang, Yujia,Chen, Kejie,Zhang, Zongke,Ma, Tao,Tang, Wenyong The Society of Naval Architects of Korea 2020 International Journal of Naval Architecture and Oc Vol.12 No.-

The pressure responsiveness property of a skirt-cushion system, which is closely related to the overall performance of Air Cushion Vehicles (ACVs), has always been the difficulty and challenging problem involving cushion aerodynamics and flexible skirt dynamics. Based on a widely used bag and finger skirt-cushion system, the pressure responsiveness properties are investigated numerically. The physical process and mechanism are analyzed and a numerical method for evaluating the pressure responsiveness property is proposed. A cushion-skirt information communication platform is also presented for interchanging the force and the skirt configuration between cushion aerodynamics and flexible skirt dynamics. The pressure responsiveness of a typical skirt-cushion system is calculated and the results demonstrate that the pressure responsiveness property helps alleviate the influence of the cushion height changing on the overall performance of ACVs. Finally, the influences of skirt geometrical and cushion aerodynamic parameters on the pressure responsiveness properties are discussed systematically, giving insight into the design of skirt-cushion systems.

Numerical investigation on pressure responsiveness properties of the skirt-cushion system of an air cushion vehicle

Xu, Shengjie,Tang, Yujia,Chen, Kejie,Zhang, Zongke,Ma, Tao,Tang, Wenyong The Society of Naval Architects of Korea 2020 International Journal of Naval Architecture and Oc Vol.12 No.1

The pressure responsiveness property of a skirt-cushion system, which is closely related to the overall performance of Air Cushion Vehicles (ACVs), has always been the difficulty and challenging problem involving cushion aerodynamics and flexible skirt dynamics. Based on a widely used bag and finger skirt-cushion system, the pressure responsiveness properties are investigated numerically. The physical process and mechanism are analyzed and a numerical method for evaluating the pressure responsiveness property is proposed. A cushion-skirt information communication platform is also presented for interchanging the force and the skirt configuration between cushion aerodynamics and flexible skirt dynamics. The pressure responsiveness of a typical skirt-cushion system is calculated and the results demonstrate that the pressure responsiveness property helps alleviate the influence of the cushion height changing on the overall performance of ACVs. Finally, the influences of skirt geometrical and cushion aerodynamic parameters on the pressure responsiveness properties are discussed systematically, giving insight into the design of skirt-cushion systems.