Viscosimeter

Claim 1

A viscosimeter comprising: a closed loop including first and second turbine flowmeters connected in series, a pump to circulate a fluid through said first and second turbine flowmeters, said first and second turbine flowmeters producing pulses at frequencies f i and f j , respectively, where the flow rate of fluid through said first and second flowmeters is Q i and Q j respectively, where Q.sub.i =m.sub.1 f.sub.i +n.sub.1 v+c.sub.1 Q.sub.j =m.sub.2 f.sub.j +n.sub.2 v+c.sub.2 Q.sub.i =Q.sub.j where m 1 , n 1 , c 1 , m 2 , n 2 and c 2 are constants and v is the viscosity of said fluid; and computer means connected to receive said pulses from both of said first and second turbine flowmeters for producing an output proportional to viscosity v as defined by v=Af.sub.j -Bf.sub.i +C, where A=m.sub.2 /(n.sub.1 -n.sub.2) B=m.sub.1 /(n.sub.1 -n.sub.2) C=(c.sub.2 -c.sub.1)/(n.sub.1 -n.sub.2) and n.sub.1 ≠n.sub.2.