水平井采油指数预测研究

由于水平井水平段井筒摩擦的存在,长水平井的产能不随水平段长度的增加而按比例无限制地增加,因此提出一种新的方法来预测长水平井在考虑井筒摩擦损失时的采油指数,该模型考虑水平井井眼附近地层的损害。研究表明,水平段长度存在一个临界点,使得井筒压降梯度突然增大而采油指数增长率突然减小。此研究可以为水平井现场设计提供理论依据。     

一种多晶硅高温压力传感器

制作压力传感器时，在二氧化硅层上淀积多晶硅膜，既可利用优良的机械特性，又可保证压敏电阻与衬底间具有良好的绝缘性，由此可大大提高器件的温度特性。介绍了一种多晶硅压力传感器的原理和设计。实验结果表明，这类传感器具有灵敏度好，精度高等特点，电路工作范围为０－２５０℃，且具有良好的温度稳定性。     

Modeling and design of a 25 MW osmotic power plant (PRO) on Bahmanshir River of Iran

Osmotic energy is one of the renewable energies. This osmotic energy source is easily obtainable all over the world where river water flows into the ocean or sea. In this article, Bahmanshir River in Iran which falls into the Persian Gulf was considered as selected place for modeling and design of 25 MW osmotic power plant in PRO method. Results indicates that for a 15 year return on investment, annual increase in purchase price of electricity 10% and interest rate 6%, sale price of electricity should be 0.4117 €/KWh which is highly expensive compared to state's suggested price of electricity from renewable source (i.e. 0.09 €/KWh).In order to balance purchase and sale price of electricity, unit price of intake and outfall, unit price of micro-filtration and interest rate should be reduced 9.1%, 15% and 25% respectively and Δλ should be increase 4.3%.     

电控高压共轨柴油机匹配的研究

在一台多缸柴油机上进行了电控共轨系统的匹配,希望能满足欧-Ⅲ的排放法规和低油耗的要求.通过试验,研究分析进气涡流强度、喷油嘴结构尺寸等参数对柴油机性能和排放的影响.结果表明：高压喷射时,随喷孔数增加,喷孔直径减小,颗粒排放显著下降,油耗降低,但NOx排放增加.     

KM496GB型柴油机机油压力低的原因分析及对策

通过对KM496GB柴油机机油压力低的试验分析表明,引起故障主要原因有:机油泵故障,限压阀未备紧,机油泵油量偏低,并介绍了所采取的相应措施。     

管芯式散热器传热与阻力特性试验研究

鉴于目前汽车管芯式散热器的研究较少,根据JB2293—78试验方法对其进行了传热与阻力试验研究。利用多参数优化拟合计算得出本次试验雷诺数范围内的管芯式散热器试件空气侧对流换热系数和阻力系数的准则关系式。试验结果表明：准则关系式关联精度较好;水管排数对该类型散热器试件换热性能和空气阻力具有较大的影响,四排管时散热器的换热性能最好。     

Condensation heat transfer and pressure drop characteristics of R-134a in an annular helical pipe

Condensation heat transfer and pressure drop data of R-134a in annular helical pipes is of significant importance to the effective design and reliable operation of helical pipe heat exchangers for refrigeration, air-conditioning, and many other applications. This paper presents the experimental investigation on condensation heat transfer and pressure drop characteristics of R-134a in an annular helical pipe. The average condensation heat transfer coefficients and pressure drops were experimentally determined for R-134a at three different saturated temperatures (35 °C, 40 °C, and 46 °C). The experimental results are compared with the data available in the literature for helical and straight pipes.     

评价柴油机燃烧噪声的新指标

人们常用最大压力升高率(dp/dφ)max值来评价柴油机的噪声、振动及工作粗暴度。但实际上, 用它来表征柴油机工作粗暴度有不尽合理之处。文中提出了评价柴油机燃烧噪声的新指标———压力振 荡的最大幅值pAmax,它只要在测录示功图时加装滤波器直接测出压力振荡波即可获得。文章阐述了燃 烧压力振荡最大幅值pAmax,这一新指标的应用可行性。     

如何控制液压系统的噪声

本文对液压系统噪声产生的原因进行了分析，并相应地介绍了控制液压系统噪声的几项具体措施，指出了在实施噪声控制过程中应注意的事项。     

阴极-敏感膜复合型真空微电子压力传感器研究

该文提出了阴极-敏感薄膜复合结构的新型真空微电子压力传感器,并研制出了阴极-敏感薄膜复合结构,对硅薄膜在外力作用下产生的形变及其应力分布进行了计算机模拟计算,并讨论了薄膜结构参数对其敏感特性的影响。