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FINITE LAYER MODEL FOR 2-D THERMAL DENSITY FLOW IN A CHANNEL

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Journal of Hydrodynamics 1996年第2期8卷 85-91页

作者： zhang, benzhao Sheng, Xinrong Zhejiang Univ Hangzhou China

The mathematical equations of 2-D thermal density flow in a channel were developed and a finite layer numerical model was established. In the direction of y, a cubic spline approximations were used for u and θ, and linear interpolation were used for du/dx and dθ/dx. The integration of differential equations along the direction of y was made with the subdomain scheme of weighted residual method. In the direction of x, the boundary value problem of differential equations was converted into an initial value problem. It is then solved by shooting method. An effective method for choosing and amending shooting multipoint initial values have been presented. The vertical distribution of u and θ at each x-section were also obtained.

关键词： Computer simulation Density of liquids Mathematical models Numerical analysis Thermal effects Viscous flow

EXPERIMENTAL STUDY OF AN ANTI-EROSION METHOD FOR BEND IN G AS-PARTICLE FLOWS

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Journal of Hydrodynamics 2000年第3期12卷 47-54页

作者： Yao, Jun zhang, benzhao Shen, Xinrong Zhejiang Univ Hangzhou China

Bend erosion is a fairly serious problem in conveyer pipe system. In this paper a new anti-erosion method for bend: ribbed anti-erosion method was introduced. An experimental research was done by fixing ribs in the range of 10°-70° on the outer wall of inside 90°-bend. As a result, the anti-erosion efficiency 93.02% was obtained in the experiments. It showed that ribbed bend technology is a simple and efficient anti-erosion method. Besides, it was found that rectangular ribs have more obvious anti-erosion effect than square ribs do when they have equal height.

关键词： Erosion Gases Particles (particulate matter) Pipe flow Sediment transport

VISCOUS FLOW BEHAVIOR IN A CURVED ANNULAR DUCT

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Journal of Hydrodynamics 1996年第2期8卷 102-110页

作者： zhang, benzhao Fan, Dahnine Shen, Xinrong Zhejiang Univ Hangzhou China

The perturbation solution of axial and secondary flow behavior in a curved annular duct was presented. First, a nonorthogonal cylindrical coordinate system was introduced. Second, the Navier-Stokes equations and continuity equation were established in tensorial form. The zeroth-order, first-order and second-order analytic perturbation solutions were obtained. It is found that there is a secondary flow in the annular section, and four recirculating cells in the cross section.

关键词： Approximation theory Ducts Nonlinear equations Perturbation techniques Pipe flow

NUMERICAL CALCULATIONS FOR TWO-PHASE JET FLOW OF A MIXTURE OF PULVERIZED-COAL AND GAS

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Acta Mechanica Sinica 1985年第1期1卷 37-48页

作者： Guo Bentie Fan Zhengqiao zhang benzhao Ding Jianmin (Department of Mechanics,Zhejiang University) 1. Department of Mechanics Zhejiang University Zhejiang China

In this paper,Euler-Lagrange type equations are used to describe the jet flow of a mixtureof pulverized-coal and gas,which is an unsteady axisymmetric two-phase *** means of the fini-te-difference method,the coal particle’s distribution,velocity and trajectory in the flow field *** coal particles are represented by a finite number of computational *** par-ticle’s diameter is randomly assigned according to a given distribution,The states of the computation-al particles are different from each *** is accounted for in a stochastic ***-cit time-splitting scheme is used to calculate the strongly coupling interphase *** numericalresults are *** comparison between the numerical results and the experiment data for thecase of the oil droplet injection shows good *** numerical technique can be extended tothe calculation of other two-phase flows of dilute particles or a droplet system.

关键词： gas-particle two-phase flow pulverized-coal injection gas injection

Erosion in Gas-Particle Flows

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Journal of Thermal Science 2000年第2期9卷 158-162页

作者： Yao Jun Fan Jianren zhang benzhao Cen Kefa (Department of Energy Engineering, Zhejiang University, Hangzhou 310027, China) Department of Energy Engineering Zhejiang University Hangzhou China

Bend erosion is a fairly serious problem in conveyer pipe system. This paper intends to introduce a new antierosion method for bend: ribbed anti-erosion method. Experimental research has been done by fixing ribs in the range of 10°- 70°on the outer-wall of inside 90°-bend. As a result the experiment got anti-erosion efficiency: 93.02%. It shows that ribbed bend technology is a simple and efficient anti-erosion method. Besides, the experiments indicate that rectangle ribs tend to do more obvious anti-erosion effect than square ribs do when they have equal height.

关键词： conveyer pipe system bend anti-erosion method experiment.

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扇环形截面弯曲管道内的粘性流动

空气动力学学报 2000年第2期18卷 216-221页

作者：章本照张金锁浙江大学杭州310027

本文利用涡量流函数法系统地研究了扇环形截面弯曲管道内的二次流动 ,计算结果表明了采用控制体积积分法对涡量流函数方程进行离散来求解弯曲管道内粘性流动问题是成功的 ,这样可以避免对压力项的处理 ;对所得结果的分析揭示了该二... 详细信息

本文利用涡量流函数法系统地研究了扇环形截面弯曲管道内的二次流动 ,计算结果表明了采用控制体积积分法对涡量流函数方程进行离散来求解弯曲管道内粘性流动问题是成功的 ,这样可以避免对压力项的处理 ;对所得结果的分析揭示了该二次流动不仅受雷诺数和曲率影响 ,而且扇形中心角。

关键词：曲线管道二次流动涡量-流函数法

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环形截面螺旋管道内二次流动特性的研究

力学学报 2001年第2期33卷 183-194页

作者：张金锁章本照浙江大学力学系杭州310027

从曲线柱坐标系下的Ｎ－Ｓ方程出发，以曲率和挠率为小参数，采用摄动法求解了环形截面螺旋管道内的黏性流动，给出了完全二阶摄动解。结果表明：当挠率为零时，二次流表现为上下对称的四个涡；当挠率不为零，涡的对称性遭到破坏，二次... 详细信息

从曲线柱坐标系下的Ｎ－Ｓ方程出发，以曲率和挠率为小参数，采用摄动法求解了环形截面螺旋管道内的黏性流动，给出了完全二阶摄动解。结果表明：当挠率为零时，二次流表现为上下对称的四个涡；当挠率不为零，涡的对称性遭到破坏，二次涡的强度和个数受Ｄｅ数和环形截面内外径之比δ的影响；轴向速度最大值在Ｄｅ数较小时靠近管道的内侧，随着Ｄｅ数的增加。

关键词：螺旋管道二次流摄动法环形截面黏性流动

异常收益、市场波动与行情变化——基于股指期货限制交易的事件研究

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金融发展研究 2017年第8期 64-70页

作者：张本照刘嘉合肥工业大学经济学院安徽合肥230601

为应对市场冲击,确保金融市场平稳发展,中金所于2015年9月7日实施一系列限制股指期货的政策。本文将中证500指数和沪深300指数的全部成分股作为研究样本,分析了该事件对市场异常收益率、波动率以及市场行情的影响。研究发现,限制股指期... 详细信息

为应对市场冲击,确保金融市场平稳发展,中金所于2015年9月7日实施一系列限制股指期货的政策。本文将中证500指数和沪深300指数的全部成分股作为研究样本,分析了该事件对市场异常收益率、波动率以及市场行情的影响。研究发现,限制股指期货的政策实施在短期有助于抑制股价波动,确保市场稳定;长期会显著降低市场的累计异常收益率,抵御市场逆向冲击作用有限。为此需加强投资者教育、完善期货市场机制建设以及健全风险管控机制,从而确保我国金融市场的长期稳定发展。

关键词：股指期货限制交易政策异常收益率异常波动

经济政策不确定性、对外直接投资和企业出口二元边际

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国际商务（对外经济贸易大学学报） 2022年第4期 71-87页

作者：张本照杨园园张燕合肥工业大学经济学院安徽合肥230601

本文从贸易成本和产品需求偏好两个视角,构建企业面对目的国经济政策不确定性时的出口决策模型,并依据中国企业对外直接投资特点,描摹了不同的对外直接投资行为对不确定性和出口两者关系的调节路径。在此基础上,运用2001—2013年中国企... 详细信息

本文从贸易成本和产品需求偏好两个视角,构建企业面对目的国经济政策不确定性时的出口决策模型,并依据中国企业对外直接投资特点,描摹了不同的对外直接投资行为对不确定性和出口两者关系的调节路径。在此基础上,运用2001—2013年中国企业数据,实证检验目的国经济政策不确定性对出口二元边际的影响效果,以及企业对外直接投资所发挥的调节效应。研究发现:目的国经济政策不确定性会显著抑制企业当前出口扩展边际,但对集约边际的影响效应不明显;中国企业对外直接投资总体上缓解了企业出口二元边际受目的国经济政策波动的冲击,但不同类型对外直接投资的调节作用具有差异性,其中商贸服务类投资的调节作用最显著;目的国经济发展水平与营商环境的差异、企业出口产品类别和企业要素密集度类型的差异,在一定程度上会影响经济政策不确定性的负面效应以及对外直接投资调节效应的大小。

关键词：经济政策不确定性出口二元边际对外直接投资贸易成本产品需求偏好