Use this window to define the rate equations for the crystal growth rate and nucleation rate.
You must supply the Rate Constant for the rate equation in ft/sec or m/sec. Growth rates are typically in the range 2E-7 to 2E-8 m/sec. By default, the rate is directly proportional to S, the Supersaturation Ratio. You may change this by overriding the default Exponential Factor, Gexp. Factors are usually in the range 0.0 to 2.5, ans has a default value of 1.0.
The Nucleation Rate RG is the number of crystals nucleated per unit time per unit liquid volume.
RG = KG SGexp
You must supply the Rate Constant KG for nucleation and specify its dimensional units. By default, the rate is directly proportional to the Supersaturation Ratio, S,
where S = (X - Xeq)/ Xeq.
X is the mole fraction of solute in the liquid and Xeq is the mole fraction of solute in the liquid at crystallizer temperature. Exponent Gexp has a default value of 1.0.
You may change this by overriding the default Exponential Factors. Typical values for the Supersaturation Ratio Factor are in the range 0.5 to 2.5 for secondary nucleation and up to 10 for primary nucleation. If an exponent is specified for the Impeller Speed, you may need to change the default value of 100 RPM.
The Crystallizer Growth and Nucleation Rates window is accessed by pressing the Growth and Nucleation Rates button on the Crystallizer Main Window.
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