Monday, 11 July 2011
MIKE FLOOD Mass Balance Check

Periodically, it is useful to perform a mass balance verification to make sure that the total volume of water entering and leaving the model at the upstream and downstream boundaries balances the quantity of water remaining in the model domain at the end of a simulation.

The calculation of mass balance is quite simple in MIKE 11 (1D only) and MIKE 21 (2D only) but a number of steps are currently required to perform the calculation in MIKE FLOOD (1D / 2D). An automated MIKE FLOOD water balance calculation (that sums the mass balance contributions from MIKE 11, MIKE URBAN and MIKE 21) is currently in development for the 2012 Release.

Several methods / tools can be used to calculate mass balance. The examples below showcase lesser known features of MIKE View and the MIKE Zero Grid Series Editor.

Assuming ∑Q_in = ∑Q_out + ΔM11_vol + ΔM21_vol

Calculate ∑Q_in and ∑Q_out using MIKE View

Launch the standard MIKE 11 results file (*.res11) in MIKE View. Choose the 'Select Gridpoints' icon or 'Plot > TS in Grid Points...'. Select 'Discharge' as the Data Type, then click 'OK'. Choose the Q-points nearest the inflow boundary to generate a Time Series Discharge plot. Right click anywhere within the plot, choose 'Accumulated Values...', then click 'Calculate'. Make a note of the accumulated discharge (m3).

Repeat for all remaining inflow / outflow boundaries.

Calculate ΔM11_vol using MIKE View

NB: Add 'Volume' results to the 'Add. Output' tab of the MIKE 11 HD Parameter file prior to running the MIKE FLOOD simulation.

Launch the additional MIKE 11 results file (*HDAdd.res11) in MIKE View. Choose 'Plot > TS of System Data...'. Select 'Volume' as the Data Type, then click 'List'. Select 'Volume, Total Volume', the click 'Show Values'. Make a note of the volumes at the start and end of the simulation.

ΔM11_vol = M11_endvol - M11_initialvol

Calculate ΔM21_vol using MIKE Zero Grid Series Editor (MIKE FLOOD 'Classic')

Launch the H,P,Q MIKE 21 results file (*.dfs2) in the Grid Series Editor (right click the results file in the Project Explorer and select 'Open With...'). Choose 'Tools > Calculate Statistics...'. Select 'Sub-Set' and navigate to the end of the simulation, then click 'Select Current'. Select the 'Statistics' tab, then make a note of the Mean Value (average water depth), the Number of Points and the model resolution (Grid spacing).

M21_endvol = H_mean * N_wetpoints * Δx * Δy

Repeat for initial volumes if applicable.

ΔM21_vol = M21_endvol - M21_initialvol

Open MIKE 21 boundaries add complexity but can be considered using the MIKE 21 Tool for Discharge Calculation (New File > MIKE 21 > MIKE 21 Toolbox > Hydrodynamics > Discharge Calculation).

For more information, please see the document 'MIKE 21 FLOW MODEL: HINTS AND RECOMMENDATIONS IN APPLICATIONS WITH SIGNIFICANT FLOODING AND DRYING' here http://www.mikebydhi.com/upload/dhisoftwarearchive/papersanddocs/hydrodynamics/MIKE21SignificantFlodryGuidelines.pdf

As a general rule of thumb, mass errors should be less than 2%. If the mass error is greater than 2%, the cause and location of the mass error within the model schematisation should be identified and the consequence of this error assessed and improvements to the model considered. If the mass error is greater than 5%, then it suggests that the model schematisation is not robust and needs to be reviewed (Ref: Fluvial Design Guide).
.

Follow Blog by E-mail

Labels

15th MIKE by DHI UK User Group Meeting (7) 16th MIKE by DHI UK User Group Meeting (18) 2014 MIKE by DHI UK Symposium (7) 2015 DHI UK and Ireland Symposium (2) 2015 DHI UK Symposium (2) 2015 MIKE by DHI UK Symposium (2) 2D modelling (1) 64-bit (1) ABM Lab (4) All-Energy (1) Aqua Republica (1) aquaculture (1) bathing water quality (4) Bird Collision (1) Blog Admin (1) Breach Assessment (2) Breach Modelling (3) Burrator Historic and Natural Environment Project (1) Burrator Reservoir (1) Catchment Management (3) catchment modelling (1) Catchment Systems (1) Central Modelling Platform (1) CIWEM (2) Cliff Recession (1) Climate Change (5) Climate Change Policy (1) Climate Change Scenario Modelling (1) Climate Change Tool (4) Cloud Computing (1) coastal erosion (1) coastal inundation (1) coastal modelling (2) Coastal Oceanography (1) Computer Aided River Management (1) Conferences (2) Contaminant Transport (1) CORFU (3) coupled groundwater and ecological models (1) coupled hydrology-hydraulic modelling (1) Coupled Models (2) CPU (1) cyclones (1) Dam break (3) data sharing (1) debris factor (1) Defra (1) DEMO (4) Devon (2) Dewatering (1) DHI (163) DHI UK & Ireland Symposium 2016 (1) Dike Structure (1) Download (1) Dredging (2) Dune Erosion (1) ECO Lab (10) Ecological modelling (5) Ecosystems (2) EIA (1) Environment Agency (2) Environmental Engineering (1) Environmental Management (1) EU Floods Directive (1) European Overtopping Manual (1) EuroTop (1) FD2320 (1) FD2321 (1) Feedback (1) FEFLOW (24) FEFLOW 2012 (3) FEFLOW 2015 (2) FEFLOW Essentials (2) FEFLOW User Conference (1) flash floods (1) Flexible mesh (7) Flood and Water Management Act 2010 (1) Flood Damage Assessment (2) Flood Defences (3) flood depth (1) Flood Forecasting (6) Flood Impact Assessment (1) Flood Modelling (10) Flood Resilience (3) Flood Risk (6) Flood Risk Assessment (5) flood risk management (1) Flood Risk Management (Scotland) Act 2009 (1) Flood Risk Regulations 2009 (1) Flood Risks to People (1) flood warning (1) flood warning systems (1) Flooding (15) Floodplains (1) Fluid mechanics (1) forecasting (3) Forum (1) FRA (1) games (1) Geothermal energy (1) GIS (1) Global Tide Model (1) Google Earth (1) GPU (3) Ground Source Energy (3) Groundwater (12) Groundwater Modellers Forum (4) Groundwater Modelling (5) Guidance (4) Hazard Mapping (4) Hazard Rating (1) High Performance Computing (1) Hotfixes (1) HPC (1) hydraulics (2) ICE (2) ice flooding 2013 (3) ICE Flooding 2014 (1) ICFR (2) Integrated 1D-2D pollutant transport modelling (1) Integrated Catchment Management (8) Integrated Catchment Modelling (3) integrated modelling (5) Integrated Surface and Groundwater (9) Integrated Water Management (5) Interactive Game (1) International Conference on Flood Resilience (2) Ivybridge (1) land use changes (1) Licensing (1) Linux (1) LITPACK (4) Managed Aquifer Recharge (1) Manning's n (1) MAR (1) Marine Monitoring (1) Marine Renewable Energy (8) marine water quality (1) Maritime Archaeological Modelling (1) MIKE 11 (12) MIKE 21 (44) MIKE 21 BW (3) MIKE 21 FM (14) MIKE 21 FMHD (1) MIKE 21 FMPT (1) MIKE 21 OS (1) MIKE 21 ST (1) MIKE 21 SW (9) MIKE 21C (1) MIKE 3 (14) MIKE 3 FMPT (1) MIKE Animator (3) MIKE Animator Plus (2) MIKE BASIN (3) MIKE by DHI (173) MIKE by DHI 2014 (11) MIKE by DHI 2016 (2) MIKE by DHI UK Symposium (1) MIKE CUSTOMISED by DHI (33) MIKE FLOOD (32) MIKE FLOOD AD (2) MIKE HYDRO (1) MIKE HYDRO Basin (3) MIKE Powered by DHI (4) MIKE SDK (1) MIKE SHE (10) MIKE software (1) MIKE to Google Earth (1) MIKE URBAN (13) MIKE Zero (1) Mine Workings (2) Miniature Sensors (1) Mining (2) Mooring Forces (1) Morphological Change (2) NAM (1) News (15) Newsletter (10) Numerical modelling (1) Offshore Wind Farms (4) Oil Spill (1) Oil Spill Modelling (4) overtopping (3) Papers (1) parallelisation techniques (1) Particle Tracking (1) Planform Change (1) Plymouth University Marine Building (1) Porous Media (1) PREPARED (1) Presentations (1) productivity tools (2) Professor Kathrine Richardson (1) Queen’s University Belfast (3) rainfall data (1) rainfall dependent infiltration (1) rainfall radar (4) RDI (1) Real time control (5) Real-time (9) real-time control (1) real-time forecasts (7) Release 2011 (8) Release 2012 (13) Release 2014 (7) Release 2016 (1) Renewable energy (12) Research (1) Reservoir Inundation Modelling (1) River Modelling (4) River Monitoring (2) river restoration (1) Roughness (1) Rural Land Management Change (3) SaaS (1) Scour (2) scour risk (1) Sediment Transport (4) Serious Games (1) Service Packs (9) Sewerage (1) Shellfish Waters Directive (1) shellfisheries (1) shoreline evolution (1) slow response runoff modelling (1) Software (7) Software as a Service (1) Software Development Kit (1) Software Updates (9) South West Lakes Trust (1) SP2 (1) Spectral Wave (1) Spillway (1) Stakeholders (1) Steve Flood (1) storm surges (2) Storm Swell (1) storm water management (1) Structures (1) SuperGen UK Centre for Marine Energy Research (1) Support (9) Surface Water Flooding (4) Surface Water Management (3) Teaching (2) THE ACADEMY by DHI (42) The Catchment Approach (2) Thermal Plume Modelling (2) three-dimensional hydrodynamics (1) Tidal and storm surge water levels (1) Tidal currents (1) Tidal Energy (6) Tidal Push (1) Tides (3) Tips (4) Training (32) Treatment (1) tsunamis (1) Turbines (1) UGM (39) UK Christmas Party 2014 (1) UKCMER (1) University (2) University of Southampton (1) Urban Drainage (8) Urban Flooding (13) urban hydrology (6) User Group Meeting (36) User Group Meeting 2013 (7) User Group Meeting 2014 (10) User Group Meeting 2015 (2) Vegetation growth (1) velocity of flood waters (1) Vessel Motion (1) Wastewater (4) Wastewater Treatment Plant (2) Water Allocation (1) Water Distribution (1) Water Framework Directive (4) Water Quality (4) water quality modelling (4) Wave Energy (5) Wave Overtopping (5) Waves (6) weather radar (1) WEST (4) Wetland Restoration (1) WFD (3) wind turbine foundations (1) Workshop (1) WWTP (4) Yelverton (1)

Welcome to DHI UK

DHI is an independent, international consulting and research organisation with the global objective of advancing technological development and competence with respect to water, in all of its environments.

Worldwide, we offer a wide range of consulting services and leading edge technologies, software tools, environmental laboratories, and physical model test facilities, as well as field surveys and monitoring programmes. Designated as a not-for-profit organisation, DHI is able to invest a considerable portion of its resources in research and development. Today we co-operate with many Universities, and research organisations, and are recognised globally for our innovation and expertise.

In the UK, DHI offers niche or specialist consultancy services in the water and environment market to government agencies, commercial entities and selected research organisations. We fulfil a research based specialist advisor role; a ‘Consultant to the Consultants’. We also supply and support the renowned MIKE by DHI suite of integrated water modelling tools.

MIKE by DHI software is the result of years of experience and dedicated development and has, in many regions, become the standard modelling tool. It transforms our science into practice and gives you the competitive edge and, through the DHI Academy, you can rest assured that there is a local team of highly skilled experts committed to train and support you every step of the way.

MIKE by DHI truly models the world of water - from mountain streams to the ocean and from drinking water to treatment plant and beyond.

DHI Profile Video

Follow DHI...

Follow DHI on Facebook   Follow DHI on Twitter   Follow DHI on YouTube