Comparison of Calculation Methods for Vapor Density

Comparison of Steam Density Calculation Methods From the above analysis, we can see that the key to the derivational steam mass flow measurement system commonly used in engineering is to obtain the steam density. In summary, there are mainly two methods of mathematical simulation and look-up table. Using mathematical models to obtain steam density In engineering design and calculation, engineers often need to obtain steam density data. The traditional method used is to check the steam density table from the steam state data. But before adopting the microprocessor, the method of this kind of manual table look-up can't be transplanted into the instrument yet, but still adopt the method of mathematical model. People have established a variety of mathematical models to meet different needs, and the most widely used ones are listed below. The disadvantage is that it is only suitable for changes in a small pressure range. When the pressure changes in a large range, it is not applicable due to too large an error. Because for saturated steam, one-only' is a curve, fit it with a straight line, the larger the range, the larger the error of course. The method to solve this contradiction is segmental fitting, that is, different coefficients and constants are used in different pressure segments. Table 3.2 shows the different density calculation formulas corresponding to different pressure segments.