VOSWMM

Importing of Scenarios

When importing a OTTHYMO project, all the scenarios of that OTTHYMO project will be imported. The settings of each scenario follows the description as below:

Scenario properties

  • Name = OTTHYMO Scenario Name
  • Description = OTTHYMO Scenario Description
  • SWMM5 Engine = SWMM5.1.015
  • Unit = CMS if OTTHYMO scenario is in metric unit and CFS if OTTHYMO Scenario is in imperial unit.
  • LinkOffset = Depth

Simulation Engine Option

  • If the imported OTTHYMO project is a single-event OTTHYMO project:
    • Report Time Step = 5 min
    • Dry Weather Runoff Time Step = 5 min
    • Wet weather Runoff Time Step = 5 min
  • If the imported OTTHYMO project is a continuous OTTHYMO project:
    • Report Time Step = OTTHYMO engine time step
    • Dry Weather Runoff Time Step = OTTHYMO engine time step
    • Wet weather Runoff Time Step = OTTHYMO engine time step

Batch Run

The same number of runs as in OTTHYMO project are created in VOSWMM. Run name is same as the run name in OTTHYMO project. Each run uses the same rain group as in OTTHYMO.

  • If the imported OTTHYMO project is a single-event OTTHYMO project:
    Start Analysis On = 01/01/2000 00:00
    Start Reporting On = Start Analysis On
    End Analysis On = Start Analysis On + the rain duration
  • If the imported OTTHYMO project is a continuous OTTHYMO project:
    Start Analysis On = the earliest date time of rainfall data in the rain group
    Start Reporting On = Start Analysis On
    End Analysis On = the last date time of rainfall data in the rain group

Snow (only when the imported OTTHYMO project is continuous OTTHYMO project)

  • Snow Pack
    • Name: SnowPack1
    • Snow Pack Parameters for Plowable, Impervious and Pervious Surface:
      • Min. Melt Coeff. = the Min value of OTTHYMO Simulation Engine Snowmelt Factor. Please note that OTTHYMO use unit of mm/hr-degC for both metric and imperial units and the unit of mm/hr-degC cannot be converted to mm/hr-degF, so only parameter values are copied in VOSWMM. When the imported OTTHYMO scenario uses imperial unit, user should check these values and make adjustment if needed.
      • Max. Melt Coeff. = the Max value of OTTHYMO Simulation Engine Snowmelt Factor. Please note that OTTHYMO use unit of mm/hr-degC for both metric and imperial units and the unit of mm/hr-degC cannot be converted to mm/hr-degF, so only parameter values are copied in VOSWMM. When the imported OTTHYMO scenario uses imperial unit, user should check these values and make adjustment if needed.
      • Fraction Free Water Capacity = OTTHYMO Simulation Engine Fraction Free Water Capacity
      • Base Temperature = the average of Snowmelt Temperature in OTTHYMO Simulation Engine. The unit and values are converted from degC to degF when imperial unit is used in OTTHYMO.
    • The SnowPack1 will be assigned at the Snow Pack field for Subcatchment.
  • Climatology Snow Melt
    • Dividing Temperature Between Snow and Rain = Snowfall Temperature in OTTHYMO Simulation Engine. The unit and values are converted from degC to degF when imperial unit is used in OTTHYMO.

Evapotranspiration (only when the imported OTTHYMO project is continuous OTTHYMO project)

  • Climatology Evaporation
    • Monthly Average Evaporation = Monthly Evaporation table in the OTTHYMO Simulation Engine