河北省张承地区风沙现状及治理对策

在分析张家口、承德地区风沙形成原因及发展趋势的基础上,提出了河北省防沙治沙工作中存在的问题,根据河北省不同类型区的自然、地理及社会经济条件,提出了风沙治理模式和建议。     

转向柱管承载能力的试验研究

在分析转向柱管花键部位应力集中情况的基础上,通过对某厂生产的转向柱管扭转破坏的试验研究,得到如下结论:①转向柱管的承载能力与其外花键齿与方向盘中心内花键齿之间的非接触区长度有关,以花键端部过渡圆弧的直径大小为宜;②安装方向盘总成时所施加在安装螺母上的拧紧力矩在70N.m左右时,转向柱管的承载能力最大。     

飞轮快速静平衡工艺

介绍了一种适应多品种小批量生产类型的飞轮快速静平衡工艺。     

Instability due to Viscosity Stratification Downstream of a Centerline Injector

A common injector geometry upstream of a static mixer is the centerline injector. A flow instability can arise due to viscosity differences between the injected core‐flow and the outer co‐flow. This instability can adversely affect the effectiveness of the mixing operation. An experimental investigation of miscible viscosity‐stratified flow in a circular geometry was performed using Laser Induced Fluorescence (LIF) and Particle Image Velocimetry (PIV). The experimental results for the stable region agree with the analytical results. The unstable region exhibits different modes depending on the viscosity ratio, volume flux ratio, and Reynolds number. The modes include wavy core‐flow with fissures and wavy core‐flow with core breakup. The time‐averaged experiment velocity profiles for the unstable core indicate a broadening of the jet at the centerline, which is consistent with the LIF visualization.     

工艺空气压缩机组开车过程的思考

通过汽轮机组调速系统伺服马达不复位、主汽门不动作，反推出电磁阀控制线路接线错误，用人为短路压力开关等手段判断出组合油脱扣器活塞卡涩是造成现场延误开车的根本原因，提出完善大机组开车工作票制度、提高人员素质等措施。     

转换波延迟时静校正

为了克服传统转换波静校正方法应用效果不佳的缺点,本文介绍一种转换波延迟时静校正方法,此法根据转换波勘探时垂直分量记录的纵波近地表模型及水平分量记录的初至时与纵波分量的初至时之差,求取转换波延迟时,并根据转换波延迟时建立横波的近地表模型,从而求取接收点的横波静校正量。文中给出了转换波延迟时静校正量的计算公式,并用实际地震数据进行了检验。结果表明此法应用效果较好,可以推广应用。目前该静校正方法已经集成到KLSeis采集软件中。     

精馏塔静态仿真：Ⅰ.静动态混合数学模型的应用

本文为了克服精馏塔静态仿真不易收敛和初值难以给定等难题，巧妙地利用隐含数值积分方法的特点，将稳态与动态数学模型耦合起来，用以求解高难度的非理想精馏塔静态仿真问题。所得静动态混俣模型大大提高了精馏塔静态仿真的鲁棒性，对于高度非理想精馏塔的仿真尤为有效。通过对某丙烯腈萃取精馏塔的静态仿真，充分证明了这种混合模型化方法的可行性。     

孔型热轧时轧制力的实用计算公式

采用修正系数法,利用板材在带刻槽的冲头进行深冲与平面冲头下深冲时的接触压力的比值确定孔型影响系数,进而推导出孔型热轧时轧制力的实用计算公式.     

An analytical expression for the power coefficient of an ideal horizontal-axis wind turbine

The paper shows that an analytical evaluation of the power coefficient C_p for an ideal horizontal-axis wind turbine can be made via an expression giving the direct relationship of C_p and the axial induction factor a. The results obtained agree closely with those obtained numerically from the usual integral expression involving several variables.     

Reduction of low-frequency pressure fluctuations in wind tunnels

The determination of dynamic wind loads on buildings, i.e. pressure and deflection, has gained increasing interest (European Prestandard ENV 1991-2-4, Eurocode 1: basis of design and actions on structures—Part 2-4: actions on structures—wind actions, European Committe for Standardization, Brussels, 1995; DIN 1055 Teil 4 Lastannahmen für Bauten, Verkehrslasten, Windlasten bei nicht schwingungsanfälligen Bauwerken, 1991; N. Hölscher, M. Hortmanns, J. Sahlem, Praxisnahe Erfassung von Windwirkung an Industrie- und Hochbauten, Windwirkung im Bauwesen, Braunschweig, 7, Dreiländertagung D-A-CH 2001, Windtechnologische Gesselschaft, 2001 [1], [2] and [3]). Therefore, the spectral distributions of velocity and pressure fluctuations in wind tunnels are an important quality aspect. While velocity fluctuations can be manipulated by the obstacles used to create the turbulence, pressure fluctuations are influenced by acoustic noise as well. Especially, the first eigenfrequency of the longitudinal mode of the wind tunnel tends to disturb the pressure spectrum.In this paper, a solution for the reduction of low-frequency acoustic pressure fluctuation is presented and its application in the atmospheric boundary layer wind tunnel at the IAG is shown.