共查询到19条相似文献,搜索用时 78 毫秒
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一、应用场合 余热已被人们普遍重视并广为利用,余热水、余热蒸汽和余热发电等是廉价的二次能源。 余热锅炉产生的蒸汽由于受工业炉窑生产工艺变化的影响,其压力和流量的大小也随之变化,直接供给用户使用很不理想,为此绝大多数余热锅炉的蒸汽管道都与集中供热的总蒸汽管网相连通,称之为“并网”。余热蒸汽并网后、当其压力和流量足够自厂和所供其他用户使用并有多余时,余热锅炉的蒸汽可输送给总蒸汽管网一部分。而余热蒸汽的压力和流量不足时,总蒸汽管网通过连通管补充其不足,保证余热蒸汽用户得到稳定压力和足够流量的蒸汽。 这样,在余热蒸… 相似文献
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基于传热原理的高温蒸汽流量测量研究 总被引:3,自引:0,他引:3
提出了一种基于传热原理高温蒸汽流量测量的新方法,分析了测试原理的可行性,并建立了依据该测试原理进行流量测量的实验台。实验结果表明,基于传热原理流量测量方法所依据的测试原理是正确的。由于该流量测量方法将流量测量问题转化为温度测量问题,因此测量误差主要取决于温度测量的准确度。 相似文献
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Tim Patten 《流程工业》2006,(3):34-36
所有流量仪表技术的应用都有它的局限性,特别是对两相流体的流量测量,比如空气混合在液体里的气、液两相流体。液体和空气混合的气.液两相流体的动态特性尤其复杂,即使运用现代的流体动态模型,很大程度上也还不能清晰地描绘它们的动态特性。所以对这种不可预知两相流体的流量测量对任何流量计包括科里奥利流量计都是充满挑战性的。[编者按] 相似文献
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对制冷剂经喷嘴并伴随有相变的流动问题进行了实验研究。实验结果表明,在相同出口压力下,随着喷嘴入口压力的提高,制冷剂的流量近似线性地增加。 相似文献
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两相流流量测量中的梯度相关法研究 总被引:3,自引:0,他引:3
梯度相关方法克服了渡越时间相关方法的缺点,对两相流流量的测量具有重要的理论和应用价值。本文设计了阵列式电容传感器、信号测量与组合电路,建立了梯度相关模型和信号采集与处理系统。通过在两相流模拟实验装置上的试验研究,获得了时间自相关,互相关,协方差,空间相关等一组函数曲线。分析表明,设计的传感器和测量系统能有效地检测和处理梯度相关信号,本方法可用来直接测量两相流中分离相的质量流量和速度。 相似文献
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介绍了目前常用的蒸汽流量测量方法--直接测量法,对其测量原理、特点及测量误差进行了分析。针 对系统工况负荷变化频繁、蒸汽流量经常出现大幅度波动、直接测量流量误差较大的问题,提出了一种流量软测 量,即无节流元件的蒸汽测量方法。利用此方法对蒸汽流量进行计算,并与实际流量计测量值对比,得出在流量波动时,流量计测量误差为10%,而软测量误差最大不超过5%。 相似文献
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在蒸汽流量的测量中、由于所测量介质实际工作状况与设计时的各项参数存在一定的差别.在这种情况下只有进行相应的修正.才能真正反映所测流量的大小.减少测量误差。 相似文献
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气-固两相流流型的检测与调节是与两相流的测量密切相关的,本文针对精确的测量往往要受众多因素影响的情况,提出了一种判断流型的新方法,通过引入领域专家的知识,改进了单纯用模糊聚类方法的不确定,建立了检测和调节的专家系统结构,进行了计算机仿真试验,运用效果良好。 相似文献
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XianglongMENG WeiCAI K.T.LAU L.M.ZHOU LianchengZHAO 《材料科学技术学报》2003,19(6):590-592
The Effect of the thermal cycling training under constant strain on the two-way shape memory effect (TWSME) in a Ti36Ni49Hfl5 high temperature shape memory alloy (SMA) has been investigated by bending tests. The results indicated that the training procedure is beneficial to get the better TWSME. The two-way shape memory strain increases with increasing the training strain. And it decreases with increasing the training temperature. The TWSME obtained in the present alloy shows poorer stability compared with that obtained in the TiNi alloys. 相似文献
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Tony Grift 《Particulate Science and Technology》2003,21(2):177-193
A generic mass flow measurement device was developed as a variation on the theme of counting. In a hypothetical infinitely sparse mass flow, the number of passing particles could be counted in a time frame and multiplied by the mean mass per particle to obtain a mass flow per time unit. In a mass flow of realistic density, however, particles travel in cluster formation and direct counting of individual particles is impossible. If a method could be available that reconstructs the original number of particles in a cluster, the mass flow can be computed for realistic clustered mass flows. This reconstruction algorithm was developed in this research; it uses the measured cluster lengths to reconstruct the total number of particles in each passing cluster. The lengths of the clusters were measured with an optoelectronic device. The reconstruction algorithm was developed using simulation, augmented by clustering theory. For identical diameter particle flow, simulation results showed that the number of particles in a cluster could be reconstructed using a very simple reconstruction formula. This formula uses only the total number of clusters per time frame and the total number of individual particles measured in the same time frame. However, identical diameter flow is not realistic, since even identical particles are measured with a certain error. Reconstruction of the realistic distributed diameter particle flow was approximated using the identical particle method. The optical mass flow sensor has major advantages over traditional methods. It is virtually insensitive to vibrations, contamination, temperature drift, and misalignment and the underlying measurement concept is well understood. But most importantly, the sensor does not require calibration. The mass flow of identical particles (4.5 mm air gun pellets) was measured with an error smaller than 3% even for high density flow rates. 相似文献