Help file has not been fully updated.
Diffusion or routing of rainfall is added. DWF is added. Routing works by spreading rainfall pulse evenly to a number of timesteps. For example, a rainfall pulse of 1 inch can be spread to 30 minutes. If each timestep is 5 minutes, each timestep gets 1/6 inch of rainfall mass. Superposition of such spreading of each rainfall pulse effectively provides routing of the runoff to the storage tank.
The diffusion time step should be greater than 1. If no routing is needed, use 1 as default value.
Average dry weather flow is added to rainfall. No routing of DWF is needed.
Mass Balance Model
"essentially, all models are wrong, but some are useful", George E. P. Box
Mass balance calculation of timeseries data, such as rainfall, is conceptually simple. However, it has to be implementation in softwares that are difficult to comprehend or time consuming to set up. The attempt here is to make it available in a browser environment. There are minimum input parameters; yet the results are useful.
Storage, Pump, Overflow Calculation
Mass balance calculation for each timestep is performed. No hydraulic routing is used.
Pseudocode: Inflow = R*C*A Loss = R - Inflow if Inflow + S > Pump Capacity Pumped = Pump Capacity Balance = Inflow + S - Pumped if Balance > Storage Capacity Overflow = Balance - Storage Capacity Balance = Balance - Overflow else Overflow = 0 Balance = Balance endif else (Inflow + S < Pump Capacity) Pumped = Inflow + S Overflow = 0 Balance = 0 endif Terminology All terms are volume, except R is depth S'= Storage Capacity S = Balance R = Rain I = Inflow P'= Pump Capacity P = Pumped O = Overflow
FOB - Federal office building raingauge
CSV - Comma separated variable file
Avg Annual - a rainfall data for SF
Design Storm - Rainfall hyetographs for SF
Rainfall data must be space or tab delimited like this: Comment can be added like this. 11/14/1979 17:05 0 11/14/1979 19:35 0.12 11/14/1979 20:15 0.24 11/14/1979 20:20 0.24 11/14/1979 20:25 0.12 11/14/1979 22:50 0.12 11/15/1979 3:45 0 11/15/1979 7:30 0.12 11/15/1979 7:35 0.12 11/15/1979 7:50 0.12 Choronologic order is not necessary. Timesteps without rain can be excluded or included. Lines not beginning with a digit character will be ignored as comments. For example, the data above along with this text can be copied into the text area without any issue.
Use at your own risk
Chart for long duration takes longer
Use 3 decimals for accumulated plot
Sanitary flow is not implemented yet.
Contact : email@example.com
copyright BS 2013
Updated 2014 Oct