GPS-X Technical Reference

113 Suspended Growth Models
General Sub-Section (Under More…)
Beta factor (for DO saturation): Specifies the DO saturation concentration correction
factor for sales, particulates, and surface-active substances. The default value is 0.95.
Temperature coefficient for K La: Specifies the temperature correction factor for K La, θ
(default value is 1.024).
Sub-Section (Under More…)
Minimum oxygen mass transfer coefficient: Specifies the minimum value of the K La
at field conditions. GPS-X bounds the field K La to be greater than or equal to this
maximum in all cases.
Maximum oxygen mass transfer coefficient: Specifies the maximum value of the K La
at field conditions. GPS-X bounds the field K La to be less than or equal to this maximum
in all cases.
Mechanical (Surface Aeration) Sub-Section (Under More…)
Mechanical aerator oxygen transfer rate: Specifies the mass of oxygen transferred to
the liquid per unit of energy used by the mechanical aerator.
Alpha factor (mechanical aeration): Wastewater correction factor for mechanical K La.
The default value is 0.9.
Diffused Air Sub-Section (Under More…)
Input air flow at… (Field Conditions/Standard Conditions): Allows user to specify
whether the diffused air flow is entered at standard conditions or field conditions. The
user can select which standard conditions are used in the
Input Parameters > Physical > More … if local conditions for O 2 solubility are used or
in the System > Input Parameters > Physical form if global conditions for O 2 solubility
are used.
Diffuser type (Fine Bubble/Coarse Bubble/Jet/User-Defined): Specifies the type of
diffuser to be used. This option is only active if diffused air has been selected. GPS-X
uses this selection to select the appropriate alpha value and to select the appropriate
SOTE correlation (if applicable).
GPS-X Technical Reference