液位、温度、密度一体化变送器多点密度的平均值是否准确可通过定性或定量2种方式进行判断。定量判断是利用对储罐内液化天然气取样化验计算得到的密度值,对来船液化天然气密度进行温度修正后得到的密度值,分别与相应时间液位、温度、密度一体化变送器多点密度的平均值进行对比进行判断。然后,选用多项式拟合的方法对定性和定量这2种密度推导出多个拟合关联公式,并利用“库存量恒等式”对公式进行筛选,可得到最接近真实密度的修正公式。
Abstract
Whether the average of the multipoint density measured by integrated transmitter of liquid level, temperature and density is accurate can be judged by qualitative way or quantitative way. One kind of density is calculated through the component of liquefied natural gas in the tank. Another kind of density is temperature modification of the incoming liquefied natural gas density. The two kinds of density compare with the mean value of multipoint density measured by LTD. This method above is quantitative judgment. Several fitting formulas are deduced for density of the two groups above using polynomial fitting method. Using the stock relation, the best correct formula can be obtained.
关键词
计量学 /
密度 /
液化天然气 /
一体化变送器 /
储罐计量 /
液位 /
温度
Key words
metrology /
density /
liquefied natural gas /
integrated transmitter /
tank metering /
liquid level /
temperature
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