Water–Glycerol Mixture Viscosity and Density Calculator
Estimate water–glycerol mixture viscosity, formulation composition, and additive-volume density from temperature and concentration.
Mixture inputs
Enter valid inputs to calculate.
Viscosity across composition
How to use
- Select Mass fraction, Component volumes, or Target viscosity.
- Enter temperature from 0 to 100 °C and the required composition or target value in the displayed units.
- Select Calculate; results also update as inputs change. Select Reset to restore the 25 °C, 90 wt% example.
- Read dynamic viscosity as the primary result. Density, kinematic viscosity, mass fraction, volume fraction, and the composition plot are supporting estimates.
- Correct any warning before using the result. A target outside pure-water and pure-glycerol limits cannot be solved.
- Do not use this model for other solutes, temperatures outside 0–100 °C, pressure-sensitive work, or precise volumetric formulation where contraction must be measured.
Equations used
- μw = 1.790 exp[((−1230 − T)T)/(36100 + 360T)] mPa·s
- μg = 12100 exp[((−1233 + T)T)/(9900 + 70T)] mPa·s
- a = 0.705 − 0.0012T; b = (4.9 + 0.036T)a2.5
- α = 1 − Cm + abCm(1 − Cm)/[aCm + b(1 − Cm)]
- μ = μwα μg(1 − α)
- ρw = 1000{1 − |(T − 4)/622|1.7}; ρg = 1277 − 0.654T, in kg/m³
- ρ = 1/[Cm/ρg + (1 − Cm)/ρw]; Cm = ρgVg/(ρgVg + ρwVw)
- φg = (Cm/ρg)/[Cm/ρg + (1 − Cm)/ρw]
- ν = 1000μ/ρ in mm²/s.
T is temperature in °C; Cm is glycerol mass fraction; Vw and Vg are water and glycerol volumes; μw, μg, and μ are dynamic viscosities; ρw, ρg, and ρ are densities; and ν is kinematic viscosity. a and b are empirical intermediate quantities; α is the Cheng mixture exponent; and φg is glycerol volume fraction. The target μtarget is inverted for Cm by bounded bisection of the same Cheng equation.
Sign conventions and limits: T is 0–100 °C; Cm and φg are fractions from 0 to 1; Vw and Vg are nonnegative with a positive total; and μ, μtarget, ρ, and ν are positive.
Assumption: density and mass/volume conversion assume additive volumes and neglect mixture contraction. The viscosity correlation applies from 0–100 °C and 0–100 wt% glycerol.
Reference: N.-S. Cheng (2008), “Formula for the Viscosity of a Glycerol–Water Mixture,” Industrial & Engineering Chemistry Research 47(9), 3285–3288. doi:10.1021/ie071349z.
