不锈钢材料高速切削技术在搅拌桨加工中的应用

应用正交实验法进行1Cr18Ni9不锈钢材料高速铣削性能实验研究,通过实验结果分析,优化不锈钢的铣削参数,确定合理的铣削方式;再结合不锈钢材料性能,借鉴高速铣削实验结论,利用5轴加工中心加工不锈钢搅拌桨,进行难加工材料高速切削关键技术应用验证.     

Numerical study on supersonic combustion of hydrogen and its mixture with Ethylene and methane with strut injection

In this paper, supersonic combustion and flow field of hydrogen and its mixture with ethylene and methane from strut injections in a Mach 2 supersonic flow are studied numerically. The fuel mixture of hydrogen, methane and ethylene represents the major products of pyrolysis of hydrocarbon fuels with large molecules such as kerosene as it acts as coolant and flows through cooling channels and absorbs heat. Detached Eddy Simulation with a reduced kinetic mechanism and steady flamelet model are applied to simulate turbulent combustion. The calculated temperature profiles of hydrogen are compared to the experimental results of DLR supersonic combustor for validation of the present numerical method. The supersonic combustion flows associated with shock waves, turbulent vortices and flame structures are studied. With addition of methane and ethylene, the flame zone moves further downstream of the strut and the maximum flow temperature at chamber exit decreases by 200 K. With analysis of total temperature ratios, it is found that combustion efficiency for hydrogen combustion is 0.91 and it decreases to 0.78 for the fuel mixture. The calculation of ignition delay time and flame speed reveals that fuel mixture of hydrogen and hydrocarbons has considerably larger delay time and smaller flame speed, that contributes to the weakened flame zone and lower combustion efficiency.     

用Levenberg-Marquardt法进行二维介质重构

对于在TM柱面波、平面波简谐波照射下,接收装置采用线状、环状装置,在有约束和没有约束情况下的目标重构,从散射的积分方程出发,采用矩量法离散该积分方程,对所得的非线性方程组采用Levenberg-Marquardt方法求解,其中对正则化因子,即阻尼因子的选取采用修正的Feltcher算法。数值结果表明该方法可以减少求解方程组的病态性,具有较好的收敛性。比较数值仿真结果,给出二维介质重构的实验设置方法。     

排灰除尘系统结垢原因及对策

阐述了宏伟热电厂除尘系统运行时存在的问题,根据系统运行流程分析了结垢原因,对垢样和回水水质取样化验,与大庆油田热电厂回水水质进行对比,认为结垢的主要原因是灰水pH值过大,引起除尘系统大面积结垢,提出加阻垢剂、加酸等处理方法,可以有效防止水垢形成.     

TMCP型屈服强度460 MPa级结构钢板的研究与开发

采用低成本的设计思路,在低C、适量Mn的基础上,组合添加Ni +Cr+ Nb+V微合金元素,优化TMCP工艺,成功生产出60 mm厚度的屈服强度460 MPa级结构钢板.轧后控制返红温度在590 ～ 610℃,使钢板得到准多边形铁素体+贝氏体+少量珠光体的混合组织,以实现良好的强韧性匹配,为生产更大厚度TMCP型钢板提...     

压煮溶出闪蒸系统注水新工艺

本文对压煮溶出多级闪蒸系统注水的必要性，和原注水工艺的优缺点进行了分析，提出了采用赤泥洗涤一次洗液注入闪蒸系统的析工艺，并介绍了实施后取得的效果。     

用导向浮阀塔盘改造含硫污水汽提塔

通过对中国石化荆门分公司含硫污水汽提塔现状分析及全面核算，提出了在尽量利用原有设备的基础上用新型高效的导向浮阀塔盘改造汽提塔的扩能方案。结果表明，处理污水能力由60t/h提高到90t／h，装置总能耗由改造前的740MJ／t下降到696MJ／t，满足了该公司对水质的要求，达到了节能降耗的目的。     

Application of vibrational parameters to locate the solid/liquid interface during solidification and melting of metals

A method to locate the solid/liquid interface with vibrational parameters during solidification is proposed for the first time. The sufficient difference in resistance to shear stresses between liquid and solid phases of metals and alloys permits the application of vibrational parameters to locate the interface in real time and in a situation during solidification. Based on the solidification theory, continuum mechanics, vibrational modal analysis and sensitivity analysis, the mechanical model and the dynamic equations of a typical Bridgman solidifying system have been established, the sensitivity of eigenvalues of the Bridgman system to the location of the solid/liquid interface has been derived, and the formulae concerned calculated. The experimental results are in good agreement with the computed ones.     

补偿中子测井曲线高分辨率处理技术的研究

本文从补偿中子测井原理入手，分析了补偿中子测井曲线纵向分辨率低的原因，指出中子测井数学转换关系和测井仪器结构是导致测井曲线纵向分辨率低的主要原因。为此，本文运用测井曲线读数随分辨率变化的规律研究提高补偿中子测井曲线纵向分辨率的方法，给出了有关技术的算法、特点和应用评价。经过在ＳＵＮ４９０和ＰＣ３８６微机上大量运算，表明该方法可行。该方法可以将补偿中子测井曲线的纵向分辨率由原来的０．６０ｍ提高到０．     

等效间隙的近似计算及误差分析

等效间隙是静压支承理论分析和计算中的一个重要参数。本文对静压支承间隙液阻的等效间隙近似计算进行了详尽的误差分析,并提出了一种更为精确的近似计算方法,这种计算方法可以满足各种偏心率工况下的静压支承的工程计算,具有较强的实用价值。