Horton (ILSAX) Hydrological Model property sheet

This window enables you to enter, view or edit rainfall-runoff models.

The data involved are:

• the name of the model (e.g. Manly Beach Model),

• depression storages (mm) for paved, supplementary and grassed areas,

• a soil type for the grassed or pervious area, normally a number between 1 and 4,

• the time of concentration formula to be used - Friend's equation or the Kinematic wave equation, which both use  the same parameters, length, slope and roughness of a flow path.
  

If you nominate You specify, the following seven parameters must be entered for this in the additional spaces that appear:  

- the antecedent rainfall depth for AMC = 1 (mm),

- the antecedent rainfall depth for AMC = 2 (mm),

- the antecedent rainfall depth for AMC = 3 (mm),

- the antecedent rainfall depth for AMC = 4 (mm),

- the Horton equation parameter, k_c (mm/h),

- the Horton equation parameter, k₀ (mm/h),

- the Horton equation parameter, k (h^-1).

​

The infiltration model parameters are listed below:

Details about the Horton (ILSAX) hydrological model are available in this Help system.

This dialog box can be used to set up two or more Horton (ILSAX) models, if required. Different models can be employed in a single network, allowing for different soils or loss conditions. While DRAINS allows you to create Horton (ILSAX) and Rational Method hydrological models together, it does not allow any runs that mix these types of model in the various sub-catchments of a stormwater drainage system.

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