Water–Glycerol Mixture Viscosity and Density Calculator

Estimate water–glycerol mixture viscosity, formulation composition, and additive-volume density from temperature and concentration.

Mixture inputs

Dynamic viscosity

—mPa·s

Enter valid inputs to calculate.

Estimated density— kg/m³
Kinematic viscosity—
Composition by mass—
Composition by volume—

Viscosity across composition

How to use

  1. Select Mass fraction, Component volumes, or Target viscosity.
  2. Enter temperature from 0 to 100 °C and the required composition or target value in the displayed units.
  3. Select Calculate; results also update as inputs change. Select Reset to restore the 25 °C, 90 wt% example.
  4. Read dynamic viscosity as the primary result. Density, kinematic viscosity, mass fraction, volume fraction, and the composition plot are supporting estimates.
  5. Correct any warning before using the result. A target outside pure-water and pure-glycerol limits cannot be solved.
  6. 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.

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