摘要
本文分析了高压蒸汽的主要特点,提出了适用于高压过热蒸汽(20—230at)的一系列近似状态方程式,包括一个适用于全部工作范围的半理论公式,和两种适用于在线计算的简化公式。这些公式与现代蒸汽表数据符合较好,其精度比过去流行的一些经验公式好得多。本文还对动力厂主蒸汽流量的测量问题进行了研究,包括标准节流件的膨胀系数的校正问题,和利用汽轮机调节级后的压力来估计流量的问题。作者提出了新的处理方法,从而得到了高度简化的计算公式,为蒸汽流量的在线计算提供了基础。
In this paper the main characteristics of high-pressure steam as compared with an ideal gas are discussed, and a serics of approximate equations of state are derived for high-pressure steam, including a semi-rational equation valid for the whole range and two simplified forms suitable for on-line calculations of steam flow. Their accuracy is far better than the older formulas still in use. The following problems in the measurement of steam flow in a power plant are also analyzed: the correction factor for compressibility of gas in standard orifices and nozzles; and a new formula for estimating the steam flow thru a turbine in terms of the pressure after the variable-admission stage. New lines of approach result in highly simplified formulas, to be used in on-line calculations.
