Hi Rob,

Sorry that I post different graphs of fitting curve and Fluent coefficents. I have try using 5 and 4 orders polynomial coefficents. The characters shown in the graph means the polynomial coefficents and the correation coefficient of polynomial formulation have reached to alomst 1. I'm sure that I entered same coefficents but the results are not that physically reasonable. I'm using the same polynomial as literature writting. I have considered piecewise linear but it cannot completely fit the water property curve ranging from 280K to 373K in 0.101Mpa so there is no wonder that the simulation would be as same as reality as possible like polynomial. CouldÂ you please give outÂ any suggestions? Should I decrease the coefficients order though it will lose someÂ precision to some degree?

Thanks