## THERMAL SCIENCE

International Scientific Journal

### A SHORT REMARK ON THE SOLUTION OF RACHFORD-RICE EQUATION

**ABSTRACT**

A fast flash calculation of the Rachford-Rice equation is very much needed in many engineering applications, especially in multi-component mixtures. This paper suggests a direct and hands-on calculation by a pocket calculator or a Chinese abacus. The calculation is based on an ancient Chinese mathematics called as He Chengtian average. An example is given to show the simplicity and effectiveness of the ancient Chinese algorithm.

**KEYWORDS**

PAPER SUBMITTED: 2017-03-03

PAPER REVISED: 2017-11-14

PAPER ACCEPTED: 2017-11-15

PUBLISHED ONLINE: 2018-09-10

**THERMAL SCIENCE** YEAR

**2018**, VOLUME

**22**, ISSUE

**Issue 4**, PAGES [1849 - 1852]

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