The problem goes down to 0.30cST. Using the equations below to find out coeficients A and B, Z always turns out to be 1, and then the viscosity is always the same.
What could be causing this?
log10 (log10 Z) = A - B log10 T(K)
where Z is given by
Z = (v + 0.7 + C − D + E) 2E7 to 0.30 cSt...