TimeStepping Properties

When evaluating the optimal time step size for the next time step, this factor is multiplied on the estimated optimal time step.

1.0 is not optimal, because then too many time steps fail. Tests has indicated values between 0.95 and 0.99 to be optimal for M11 type setups and between 0.8 and 0.9 for MU type setups.

Default value is 0.9

Maximum acceptable relative change of boundary value, Adaptive Time Stepping |resid(BC)/BC| Also called "dDelB_BVal".

Adaptive Time Stepping |resid(BC)/BC|. For boundary values less than this, the boundary check is not performed.

Also called "dDelB_BLim"

Adaptive Time Stepping Courant AD

Adaptive Time Stepping Courant HD

If CrossSectionChecksRelativeToMaximumValues is true, then changes to cross section values are relative to maximum values. If it is false, then changes are relative to durrent values

If PerformCrossSectionChecks is true, then cross section values cannot vary more than CrossSectionChecksMaximumRelativeVariation times either max values or current values (depending on the value of CrossSectionChecksRelativeToMaximumValues)

Cross sections are only checked if the relative water depth is above this limit.

When PerformDepthRelativeCheck, then the change in relative depth change must be less than RelativeDepthLimit. For small relative depths (below this limit), the limit value used is decreased down to a minimum of 0.02 when the relative depth is zero.

This is ony evaluated in closed part of the network.

Default value is 0.1. This cannot be below 0.02.

Largest acceptable discharge change |dQ|. Also called "dDelQVal".

Largest acceptable relative discharge change |dQ/Q|. Also called "dDelQ_QVal".

Limit value for when relative discharge check is enabled, for |Q| less than this limit, the check is skipped. Also called "dDelQ_QLim".

Adaptive Time Stepping fixed dt. Also used for Tabulated time stepping.

For adaptive time stepping this defines a fixed overall timestep that the adaptive time stepping procedure should hit exactly. It can e.g. be used to assure if results are printed exactly every hour, that the model hits that hour exactly.

It must be larger than DtMax.

If not applicable, set to Zero, which is the default.

Adaptive Time Stepping Maximum dt

Adaptive Time Stepping Minimum dt

Time between file flushes. Set to Zero to disable file flushes.

Default value is 10 seconds.

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Initial time step in seconds. If TimeSteppingType is fixed, this is the timestep used during the entire simulation. Unit: [sec]

Tabulated time step Item Number

If true, then check boundaries during Adaptive Time Stepping

Adaptive Time Stepping Courant AD

Adaptive Time Stepping Courant HD

If true, then perform checks on cross section flow area, water level, and surface area (MIKE URBAN method)

If true, then relative water depth is checked in h-grid points (MIKE URBAN method)

Only performed for closed cross sections.

Enable checking of discharge change |dQ|

Enable checking of relative discharge changes |dQ/Q|.

If true, then check runoff inflow during Adaptive Time Stepping. It is using the same limits as the PerformBoundaryCheck.

If true, then let structures calculate their preferred time step size

Enable checking of water level changes |dh|

Enable checking of relative water level changes |dh/depth|

When a pump is accelerating or decelerating, this factor defines the maximum time step accepted by the pump.

A value of zero specifies that the DtMin time step will be used, and a value of one specifies that the DtMax time step is acceptable.

Default value is zero, meaning that when pumps are accelerating or decelerating, the simulation will run with DtMin.

Tabulated time step Filename

Tabulated time step Filename

Maximum factor with which the time step can be increased. A value of 1.3 means that the timestep can only increase with 30%. Decrease of time step is not limited. Defaults to 2.

Type of time stepping taking place

Largest acceptable water level change |dh| Also called "dDelhVal"

Largest acceptable relative water level change |dh/depth| Also called "dDelh_hVal"

Limit value for when relative water level check is enabled, for depth less than this limit, the check is skipped. Also called "dDelh_hLim"