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DELWAQ

DELWAQ is the engine of the D-Water Quality and D-Ecology programmes of the Delft3D suite. It is based on a rich library from which relevant substances and processes can be selected to quickly put water and sediment quality models together.

The processes library covers many aspects of water quality and ecology, from basic tracers, dissolved oxygen, nutrients, organic matter, inorganic suspended matter, heavy metals, bacteria and organic micro-pollutants, to complex algae and macrophyte dynamics. High performance solvers enable the simulation of long periods, often required to capture the full cycles of the processes being modelled.

The finite volume approach underlying DELWAQ allows it to be coupled to both the structured grid hydrodynamics of the current Delft3D-FLOW engine and the upcoming D-Flow Flexible Mesh engine (1D-2D-3D) of the Delft3D Flexible Mesh Suite (or even other models such as TELEMAC).

'DELWAQ in open source' is our invitation to all leading experts to collaborate in further development and research in the field of water quality, ecology and morphology using Delft3D. Feel free to post your DELWAQ related questions or comments in this dedicated forum space. If you are new to DELWAQ, the tutorial (in the user manual) is a good place to start. A list of DELWAQ related publications is available here.

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Sub groups
D-Flow Flexible Mesh
DELWAQ
Cohesive sediments & muddy systems

 

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inconsistency in DIMENSIONAL ANALYSIS

SN
Sathya narayanan, modified 5 Years ago.

inconsistency in DIMENSIONAL ANALYSIS

Youngling Posts: 3 Join Date: 3/13/14 Recent Posts
Hello,
With reference to page no. 350 in D-Water Quality Technical reference manual (Version: 5.01.34078) dated 26 May 2014, i found that there seems to be inconsistency in DIMENSIONAL ANALYSIS. The term kmrd has the unit (d-1), but the product of UNITS of the terms krd, DL ,fuv , I0 and (1 - e^-epsxH)/epsxH) become UNIT LESS which is completely contradicting. Would anyone help me in giving the correct terms with proper UNITS?


Formulation

The mortality rate of coliform bacteria can be quantified with the following empirical function
of temperature, chlorinity and solar radiation (as derived from visible light):
For T > Tci:

Rmrti = kmrti x Cxi

kmrti = (kmbi + kmcli) x ktmrti^(T-20) + kmrd
kmcli = kcli x Ccl
kmrd = krd x DL x fuv x I0 x (1 - e^-epsxH)/epsxH

For T <= Tci:
Rmrti = 0:0

where:
Cx concentration of coliform bacteria species i [MPN.m-3]
DL daylength [d]
eps extinction of UV-radiation [m-1]
fuv fraction of UV-radiation as derived from visible light [-]
H water depth [m]
I0 daily solar radiation as visible light at the water surface [W.m-2]
kcl chloride related mortality constant [m3.g-1.d-1]
kmb basic mortality rate [d-1]
kmcl chloride dependent mortality rate [d-1]
kmrd radiation dependent mortality rate [d-1]
kmrt first order mortality rate [d-1]
krd radiation related mortality constant [m2.W-1.d-1]
ktmrt temperature coefficient of the mortality rate [-]
Rmrt mortality rate of coliform bacteria [MPN.m-3.d-1]
T temperature [°C]
Tc critical temperature for mortality [°C]
Ccl chloride concentration [g.m-3]
i index for coliform species, ECOLI, FCOLI, TCOLI and ENCOC


Thanks
AA
Anonymous Anonymous, modified 5 Years ago.

RE: inconsistency in DIMENSIONAL ANALYSIS

Jedi Master Posts: 333 Join Date: 7/30/20 Recent Posts
Hi Sathya,

I think you can consider daylength as a fraction here, hence without units, which yields [d-1] fro kmrd.

Regards