自然循环锅炉汽包寿命计算及影响因素分析

文中叙述了汽包寿命的计算方法，并针对各种运行工况计算出寿命消耗量，根据理论计算结果分析影响汽包寿命的主要因素，提出了增加汽包寿命的方法。     

计算铁心附加损耗系数的公式推导及其验证

阐述了铁心空载损耗产生的原因，分析推导了二片一叠铁心附加损耗系数的计算公式，给出了不同结构铁心附加损耗系数的计算式，并通过实例加以验证。     

惯性、刚性振动出矿机合理振动形态设计理论探讨

简要地讨论了惯性、刚性振动出矿机在三个自由度下运动的解答;并根据实际使用情况,提出了振动出矿机合理振动形态的概念及条件。从理论上导出了求得合理振动形态的设计方法及计算公式。     

有教师的线性基本函数前向三层神经网络结构研究

优化选择隐节点数是人们在应用基于误差反传算法的有教师的线性基本函数前向三层神经网络过程中首先遇到的一个十分重要而又困难的问题。本文从国内外大量应用裕列中陪结归纳出了一个初定这种网络隐节点数的经验公式，提出了一种判断所选隐节点数是否多余的具体方法，并从理论上做了详细的推导。     

Heat transfer coefficients for forced-air cooling and freezing of selected foods

To maximize the efficiency of cooling and freezing operations for foods, it is necessary to optimally design the refrigeration equipment to fit the specific requirements of the particular cooling or freezing application. The design of food refrigeration equipment requires estimation of the cooling and freezing times of foods, as well as the corresponding refrigeration loads. The accuracy of these estimates, in turn, depends upon accurate estimates of the surface heat transfer coefficient for the cooling or freezing operation. This project reviewed heat transfer data for the cooling and/or freezing of foods. A total of 777 cooling curves for 295 food items were obtained from an industrial survey and a unique iterative algorithm, utilizing the concept of ‘equivalent heat transfer dimensionality’, was developed to obtain heat transfer coefficients from these cooling curves. Nine Nusselt–Reynolds–Prandtl correlations were developed from a selection of the 777 heat transfer coefficients resulting from this algorithm, as well as 144 heat transfer coefficients for 13 food items, collected from the literature. The data and correlations resulting from this project will be used by designers of cooling and freezing systems for foods. This information will make possible a more accurate determination of cooling and freezing times and corresponding refrigeration loads. Such information is important in the design and operation of cooling and freezing facilities and will be of immediate usefulness to engineers involved in the design and operation of such systems.     

Ice slurries phase transition thermodynamics: relations for determining concentration–temperature domains of application

Criteria for calculation of the concentration–temperature domain of use of ice slurries are defined, which allows establishing a temperature–concentration chart relating the temperature and the antifreeze mass fraction. It is shown that the shape of the chart depends only on the thermodynamic properties (heat capacity, ice–liquid equilibrium, etc.) of the diluted substance.     

Calculating the elastic moduli of steel-fiber reinforced concrete using a dedicated empirical formula

The equivalent inclusion method (EIM) is adopted to study the characteristics of the equivalent material properties of steel-fiber reinforced concrete as a function of the volume fraction and the length to diameter ratio of the fibers. It is found that the equivalent material moduli of concrete reinforce with randomly orientated and distributed fibers are insensitive to the length to diameter ratio of the steel fibers. A set of empirical formulae is then proposed for the purposes of engineering applications. The proposed empirical model can simplify the calculation of the equivalent material moduli. Verifications of the proposed empirical formulae with the EIM model and with experimental data are performed with two examples. The first is a compression test. The second is 4 point bending test. The empirical formulae, based on the equivalent inclusion method proposed in this study, represent an alternative means of quickly calculating the effective elastic modulus of steel-fiber reinforced concrete materials.     

万向联轴器法兰叉架的法兰强度计算及厚度确定

分析了万向联轴器法兰叉架的法兰破坏的原因 ,对法兰不同轴向截面进行受力分析 ,提出法兰厚度的计算公式。用这个计算公式可以对承担任何公称扭矩的任何轴向截面的法兰叉架的法兰进行强度计算及厚度确定。     

离心压缩机组冷态找正数据的分析与精确计算

针对在安装引进的离心压缩机组中发现的原机组冷态找正数据与实测值不符的情况，介绍了其试验的方法，并提出了一种行之有效的精确计算方法。用该方法计算了该压缩机组的冷态找正数据，并与实测数据作了比较。从而证明该计算方法的可行性及正确性。     

微机控制流量及热耗量积算仪的研制

本文介绍了一种采用单片微机构成的流量积算仪。该仪表具有两路流量信号及两路温度信号输入，不仅能对流量，还能对热（冷）耗量进行精确的检测及累计。仪表可靠性好，精度高，操作方便，适用于各种需对热（冷）耗量进行计量的场合。