Nomenclature: Difference between revisions

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* Dumping a sketch would be useful
* Dumping a sketch would be useful


{| class="wikitable"
|- Style="font-weight:bold; "
! Parameter name
! Symbol
! Description
! Standard long name
! Units
|-
|EAST_VEL
| <math> u </math>
| zonal velocity
| eastward_velocity
| m s-1
|-
|NORTH_VEL
| <math> v </math>
| meridional velocity
| northward_velocity
| m s-1
|-
|UP_VEL
| <math> W </math>
| vertical velocity
| upward_velocity
| m s-1
|-
|ERROR_VEL
| <math> u </math>
| error velocity
| error_velocity
| m s-1
|-
|U_VEL
| <math> U </math>
| velocity parellel to mean flow
| meanflow_velocity
| m s-1
|-
|V_VEL
| <math> V </math>
| velocity perpendicular to mean flow
| crossflow_velocity
| m s-1
|-
|Drop_Speed
| <math> W_d </math>
| Profiler fall speed
| mean_drop_speed
| m s-1
|-
|FlowPast_Speed
| <math> U_fp </math>
| Flow speed past sensor
| mean_velocity_past_turbulence_sensor
| m s-1
|-
|}


== Reynold's Decomposition ==
== Reynold's Decomposition ==
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{| class="wikitable"
{| class="wikitable"
|- Style="font-weight:bold; "
|- Style="font-weight:bold; "
! Parameter name
! Symbol
! Symbol
! Description
! Description
! Standard long name
! Eqn
! Eqn
! Units
! Units
|-
|-
| EPSI
| <math>\epsilon</math>
| <math>\epsilon</math>
| Turbulent kinetic energy dissipation
| Turbulent kinetic energy dissipation
| tke_dissipation
|
|
| W/kg
| W/kg
|-
|-
| RI
| <math>Ri</math>
| <math>Ri</math>
| Richardson number
| Richardson number
| richardson_number
| <math> Ri = \frac{N^2}{S^2}</math>
| <math> Ri = \frac{N^2}{S^2}</math>
|  
|  
|-
|-
| RI_F
| <math>Ri_f</math>
| <math>Ri_f</math>
| Flux gradient Richardson number
| Flux gradient Richardson number
| flux_grad_richardson_number
| <math> \frac{B}{P} </math> or Ivey & Immerger?  
| <math> \frac{B}{P} </math> or Ivey & Immerger?  
|  
|  
|-
|-
| <math>\kappa</math>
| Krho
| <math>\kappa_\rho</math>
| Turbulent diffusivity
| Turbulent diffusivity
| turbulent_diffusivity
| <math> \kappa = \Gamma \epsilon N^{-2} </math>
| <math> \kappa = \Gamma \epsilon N^{-2} </math>
| m<math>^2</math>s<math>^{-1}</math>
| m<math>^2</math>s<math>^{-1}</math>
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{| class="wikitable"
{| class="wikitable"
|- Style="font-weight:bold; "
|- Style="font-weight:bold; "
! Parameter Name
! Symbol
! Symbol
! Description
! Description
! Standard long name
! Eqn
! Eqn
! Units
! Units
|-
|-
| S
| <math>S</math>
| <math>S</math>
| Background velocity shear
| Background velocity shear
| background_velocity_shear
| <math> S = \frac{\partial |U|}{\partial z}</math>
| <math> S = \frac{\partial |U|}{\partial z}</math>
| s<math>^{-1}</math>
| s<math>^{-1}</math>
|-
|-
| KVISC35
| <math>\nu</math>
| <math>\nu</math>
| Viscosity of water for seawater at 35psu and 20 oC
| Kinematic viscosity of water for seawater at 35 and 20 <math>^o</math>C
| seawater_kinematic_viscosity_at_35psu
| <math> 1\times 10^{-6}</math>
| <math> 1\times 10^{-6}</math>
| m2/s
| m2/s
|-
|-
| N
| <math>N</math>
| <math>N</math>
| Background stratification, i.e buoyancy frequency
| Background stratification, i.e buoyancy frequency
| background_buoyancy_frequency
| <math> N = \sqrt{\frac{-g}{\bar{\rho}} \frac{\partial\bar{\rho}}{\partial z}}</math>
| <math> N = \sqrt{\frac{-g}{\bar{\rho}} \frac{\partial\bar{\rho}}{\partial z}}</math>
| rad/s
| rad/s
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{| class="wikitable"
{| class="wikitable"
|- Style="font-weight:bold; "
|- Style="font-weight:bold; "
! Parameter
! Symbol
! Symbol
! Description
! Description
! Standard long name
! Eqn
! Eqn
! Units
! Units
|-
|-
| Tn
| <math>\tau_N</math>
| <math>\tau_N</math>
| Buoyancy timescale
| Buoyancy timescale
| buoyancy_time_scale
| <math> \tau_N = \frac{2\pi}{N}</math>
| <math> \tau_N = \frac{2\pi}{N}</math>
| s
| s
|-
|-
| L_E
| <math>L_E</math>
| <math>L_E</math>
| Ellison length scale (limit of vertical displacement without irreversible mixing)
| Ellison length scale (limit of vertical displacement without irreversible mixing)
| Eliison_lenght_scale
| <math>L_E=\frac {\langle \rho'^2\rangle^{1/2}}{\partial \overline{\rho}/\partial z}</math>
| <math>L_E=\frac {\langle \rho'^2\rangle^{1/2}}{\partial \overline{\rho}/\partial z}</math>
| m  
| m  
|-
|-
| L_RHO
| <math> L_\rho</math>
| <math> L_\rho</math>
| Density length scale
| Density length scale
| density_length_scale
| <math> L_\rho </math>
| <math> L_\rho </math>
| m
| m
|-
|-
| L_S
| <math>L_S</math>
| <math>L_S</math>
| Corssin length scale  
| Corssin length scale
| Corssin_shear_length_scale
| <math> L_S = \sqrt{\epsilon/S^3} </math>
| <math> L_S = \sqrt{\epsilon/S^3} </math>
| m
| m
|-
|-
| L_K
| <math>\eta</math>
| <math>\eta</math>
| Kolmogorov length scale (smallest overturns)
| Kolmogorov length scale (smallest overturns)
| Kolmogorov_length_scale
| <math>\eta=\left(\frac{\nu^3}{\epsilon}\right)^{1/4}=\frac{1}{2\pi\hat{k}_K}</math>
| <math>\eta=\left(\frac{\nu^3}{\epsilon}\right)^{1/4}=\frac{1}{2\pi\hat{k}_K}</math>
| m  
| m  
|-
|-
| L_O
| <math>L_o</math>
| <math>L_o</math>
| Ozmidov length scale, measure of largest overturns in a stratified fluid
| Ozmidov length scale, measure of largest overturns in a stratified fluid
| Ozmidov_stratification_length_scale
| <math>L_o=\left(\frac{\epsilon}{N^3}\right)^{1/2}</math>
| <math>L_o=\left(\frac{\epsilon}{N^3}\right)^{1/2}</math>
| m  
| m  

Revision as of 14:43, 31 March 2021

Frame of reference

  • Define frame of reference, and notation. Use u,v,w and x,y, and z?
  • Dumping a sketch would be useful
Parameter name Symbol Description Standard long name Units
EAST_VEL <math> u </math> zonal velocity eastward_velocity m s-1
NORTH_VEL <math> v </math> meridional velocity northward_velocity m s-1
UP_VEL <math> W </math> vertical velocity upward_velocity m s-1
ERROR_VEL <math> u </math> error velocity error_velocity m s-1
U_VEL <math> U </math> velocity parellel to mean flow meanflow_velocity m s-1
V_VEL <math> V </math> velocity perpendicular to mean flow crossflow_velocity m s-1
Drop_Speed <math> W_d </math> Profiler fall speed mean_drop_speed m s-1
FlowPast_Speed <math> U_fp </math> Flow speed past sensor mean_velocity_past_turbulence_sensor m s-1

Reynold's Decomposition

  • Variable names for Decomposition of total, mean, turbulent and waves.


Turbulence properties

Parameter name Symbol Description Standard long name Eqn Units
EPSI <math>\epsilon</math> Turbulent kinetic energy dissipation tke_dissipation W/kg
RI <math>Ri</math> Richardson number richardson_number <math> Ri = \frac{N^2}{S^2}</math>
RI_F <math>Ri_f</math> Flux gradient Richardson number flux_grad_richardson_number <math> \frac{B}{P} </math> or Ivey & Immerger?
Krho <math>\kappa_\rho</math> Turbulent diffusivity turbulent_diffusivity <math> \kappa = \Gamma \epsilon N^{-2} </math> m<math>^2</math>s<math>^{-1}</math>

Fluid properties and background gradients for turbulence calculations

Parameter Name Symbol Description Standard long name Eqn Units
S <math>S</math> Background velocity shear background_velocity_shear U|}{\partial z}</math> s<math>^{-1}</math>
KVISC35 <math>\nu</math> Kinematic viscosity of water for seawater at 35 and 20 <math>^o</math>C seawater_kinematic_viscosity_at_35psu <math> 1\times 10^{-6}</math> m2/s
N <math>N</math> Background stratification, i.e buoyancy frequency background_buoyancy_frequency <math> N = \sqrt{\frac{-g}{\bar{\rho}} \frac{\partial\bar{\rho}}{\partial z}}</math> rad/s

Theoretical Length and Time Scales

Parameter Symbol Description Standard long name Eqn Units
Tn <math>\tau_N</math> Buoyancy timescale buoyancy_time_scale <math> \tau_N = \frac{2\pi}{N}</math> s
L_E <math>L_E</math> Ellison length scale (limit of vertical displacement without irreversible mixing) Eliison_lenght_scale <math>L_E=\frac {\langle \rho'^2\rangle^{1/2}}{\partial \overline{\rho}/\partial z}</math> m
L_RHO <math> L_\rho</math> Density length scale density_length_scale <math> L_\rho </math> m
L_S <math>L_S</math> Corssin length scale Corssin_shear_length_scale <math> L_S = \sqrt{\epsilon/S^3} </math> m
L_K <math>\eta</math> Kolmogorov length scale (smallest overturns) Kolmogorov_length_scale <math>\eta=\left(\frac{\nu^3}{\epsilon}\right)^{1/4}=\frac{1}{2\pi\hat{k}_K}</math> m
L_O <math>L_o</math> Ozmidov length scale, measure of largest overturns in a stratified fluid Ozmidov_stratification_length_scale <math>L_o=\left(\frac{\epsilon}{N^3}\right)^{1/2}</math> m

Turbulence Spectrum

Taylor's Frozen Turbulence for converting temporal to spatial measurements <math>\left(\bar{u}_1\frac{\partial }{\partial{x}} = \frac{\partial}{\partial{t}}\right)</math>


  • Missing the y-axi variable. CEB proposes:
    • <math>\Psi_{variable}</math> for model/theoretical spectrum of variable e.g., du/dx or u
    • <math>\Phi_{variable}</math> for observed spectrum of variable e.g., du/dx or u
  • Lowest frequency and wavenumber resolvable
Symbol Description Eqn Units
<math>\Delta t</math> Sampling interval <math> \frac{1}{f_s} </math> s
<math>\Delta s</math> Sampling volume dimension m
<math>f</math> Frequency <math>\frac{\omega}{2\pi}</math> Hz
<math>f_n</math> Nyquist frequency <math>f_n=0.5f_s</math> Hz
<math>f_s</math> Sampling frequency <math>f_s=\frac{1}{\Delta t} </math> Hz
<math>k</math> Wavenumbers (angular) <math>k=\frac{f}{\bar{u}}=2\pi\hat{k}</math> rad/m
<math>\hat{k}</math> Wavenumbers <math>\hat{k}=\frac{k}{2\pi}</math> cpm
<math>\hat{k}_\Delta</math> Nyquist wavenumber, based on sampling volume's size <math>\Delta l</math> <math>\hat{k}_\Delta=\frac{0.5}{\Delta l}</math> cpm
<math>\hat{k}_n</math> Nyquist wavenumber, via Taylor's hypothesis (temporal measurements) <math>\hat{k}_n=\frac{f_n}{u}</math> cpm
<math>\omega</math> Angular frequency <math>2\pi f</math> rad/s

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