Difference between revisions of "Notation"

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;N :Number of days in the month
;N :Number of days in the month


;P :Perimeter of infiltration practice or swale x-section (m)
;x :Perimeter of infiltration practice or swale x-section (m)


;q :Infiltration rate in (length per time, usually mm/hr)
;f':Design infiltration rate (length per time, usually mm/hr) after application of safety correction factor (SCF)
 
;q':Infiltration coefficient in (length per time, usually mm/hr) after application of safety correction factor (SCF)


;Q<sub>p</sub> :Peak flow in units of volume per time (e.g. m<sup>3</sup>/s)
;Q<sub>p</sub> :Peak flow in units of volume per time (e.g. m<sup>3</sup>/s)
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;R<sub>b</sub> :Rise of compensation gradient for an enhanced swale (length, usually m)
;R<sub>b</sub> :Rise of compensation gradient for an enhanced swale (length, usually m)


;RVC<sub>T</sub> :Runoff volume control target (as outlined by MOECC, units are mm)
;RVC<sub>T</sub> :Runoff volume control target (as outlined by MECP, units are mm)


;S<sub>0</sub> :Longitudinal slope (m/m, i.e. dimensionless)
;S<sub>0</sub> :Longitudinal slope (m/m, i.e. dimensionless)
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;V :Volume (usually in m<sup>3</sup>)
;V :Volume (usually in m<sup>3</sup>)


;V<sub>R</sub> :Void ratio, as usually applied to aggregates and yard materials. In this guide, it is also applied to native soils in lieu of porosity (unit for both are vol/vol, i.e. dimensionless)
;n :Porosity, applies to aggregate and other void-forming materials, filter media and native soils (unit is vol/vol, so dimensionless)


;y :Depth of water (L, usually m or sometimes mm)
;y :Depth of water (L, usually m or sometimes mm)

Revision as of 16:40, 22 April 2020

Ac
Area of the catchment, whole contributing drainage area (usually in m2).
Ap
Area of the practice e.g. footprint area of a bioretention cell (usually in m2)
d
Depth e.g. of an infiltration practice (units of length, usually mm or m)
f
Infiltration rate (usually mm/hr)
h
height (units of length)
i
Thornthwaite monthly heat index (-)
I
Thornthwaite annual heat index (-)
L
Length, e.g. of a reach, channel or swale (usually in m)
m
run of side slopes in channel cross sections (length, but usually expressed as a ratio in relation to rise. e.g. side slopes = 1:3, so m = 3)
n
Manning's coefficient (unitless) Note: for clarity porosity is being expressed as 'void ratio' and sharing the notation VR
N
Number of days in the month
x
Perimeter of infiltration practice or swale x-section (m)
f'
Design infiltration rate (length per time, usually mm/hr) after application of safety correction factor (SCF)
Qp
Peak flow in units of volume per time (e.g. m3/s)
R
Ratio of catchment (Ac) to the practice footprint area (Ap). syn. I/P ratio. For green roofs (and often permeable paving systems) this will be 1:1. In bioretention it may be 15 or 20 to 1.
Ra
Existing rise of swale gradient (length, usually m)
Rb
Rise of compensation gradient for an enhanced swale (length, usually m)
RVCT
Runoff volume control target (as outlined by MECP, units are mm)
S0
Longitudinal slope (m/m, i.e. dimensionless)
ST
Storage (m3)
Sx
Cross slope (m/m, i.e. dimensionless)
SCF
Safety correction factor (dimensionless)
t
time (usually in hrs)
T
Temperature (°C)
V
Volume (usually in m3)
n
Porosity, applies to aggregate and other void-forming materials, filter media and native soils (unit is vol/vol, so dimensionless)
y
Depth of water (L, usually m or sometimes mm)