API ch 11 1

[harrypapas]

I have a question regarding a calculation using the section 11.1.7.2 routine of API. I have more details in the attachment.In short, no matter what I have tried I cannot get the results of the routine to agree with those of table 53B when the "Transition zone" Ks are used.

Harry

 

[f1636]

I can think of several possibilities for the differences.
1) The current algorithms have superceded the previous printed tables. You should not expect to calculate the same results as appear in older printed tables.
2) Again with regard to older printed tables, consider the following comment from the current standard: "Unlike previous editions of the VCF tables there are no provisions to correct density measurements with a glass hydrometer. It is essential that only corrected hydrometer values be used in conjunction with these tables. Glass hydrometer values should be corrected consistent with directions from the hydrometer manufacturer and appropriate glass hydrometer standard. The odd-numbered 1980 Tables all included a hydrometer correction. Because of this, the odd-numbered tables generated by the algorithm in this Standard will not be identical to the corresponding oddnumbered 1980 Tables. Appendix A includes a discussion of the hydrometer corrections used in the 1980 CTL Tables."
I hope this helps.