Sartorius Cubis MSU116P User Manual page 92

Density Determination
Displacement:
®
92 Cubis MSU User Manual
Calculation Basis for Density Determination
The density determination application is based on the equations:
Rho Density of sample ( )
Density of buoyancy liquid
fl
W
Weight of sample in air
a
W
Weight of sample in liquid (when determining liquid density, buoyancy
fl
and displacement)
Weight of fill medium (for pycnometer)
W Weight of sample and fill medium (for pycnometer)
r
LA Air buoyancy correction = 0.0012 g/ccm
Buoyancy: Rho = (W * (
a
Rho = (W * (
a
When the displacement method is used to correct for buoyancy by means of a wire
(string) suspended in liquid, the factor 1.00000 is used in the calculation as
a factory-set default.
The correction factor Corr is calculated from: Corr = 1 - n * d
with:
n
Number of wires
d Wire diameter (YKD01MS: 0.7 mm)
D Inner diameter of the vessel being used (YKD01MS: 76 mm)
When other vessels or other submersion assemblies are used, this factor can
be changed by modifying the parameters for the density kit.
- LA)) / ((W - W ) * corr) + LA
fl a fl
- LA)) / (W * corr) + LA
fl fl
2 2
/ D