.. _section-7.nomenclature:
Nomenclature
-------------
.. list-table::
:header-rows: 1
:align: center
:widths: auto
* - Symbol
- Definition
- Units
* - :math:`a`
- Constant :math:`\left( 9.325 \times 10^{-2} \right)`
-
* - :math:`a_{0}, a_{1}, a_{2}, a_{3}`
- Momentum equation coefficients
-
* - :math:`A`
- Flow area
- :math:`m^{2}`
* - :math:`b`
- Constant :math:`\left( 2.356 \times 10^{-4} \right)`
-
* - :math:`B`
- Valve damping coefficient
- :math:`kg - m / s`
* - :math:`c, c_{p}`
- Specific heat
- :math:`J / kg - K`
* - :math:`c_{b}`
- Bucket coefficient
-
* - :math:`c_{n}`
- Nozzle velocity coefficient
-
* - :math:`c_{r}`
- Reaction coefficient
-
* - :math:`C`
- Valve calibration constant
- :math:`m^{2}`
* - :math:`CF`
- Calibration factor
-
* - :math:`CV`
- Elevation of heater center
- :math:`m`
* - :math:`C_{1},\ C_{2},\ C_{3},\ C_{4}`
- Coefficients in the expression for the Moody friction factor (\ :math:`C_{1}=0.0055`, :math:`C_{2}=20000`, :math:`C_{3}=106`, and :math:`C_{4}=1/3`\ )
-
* - :math:`D_{h},\ D_{H}`
- Hydraulic diameter
- :math:`m`
* - :math:`\widehat{E}`
- Total energy
- :math:`J / kg`
* - :math:`f_{l}`
- Liquid friction factor
-
* - :math:`f_{tp}`
- Two-phase friction factor
-
* - :math:`F`
- Force
- :math:`N`
* - :math:`F`
- Heat flux
- :math:`W / m^{2}`
* - :math:`F`
- Pressure loss coefficient
-
* - :math:`FL`
- Fouling resistance
- :math:`m^{2} - K / W`
* - :math:`FR`
- Friction calibration coefficient
-
* - :math:`F_{1}`
- Valve driving function
- :math:`kg - m / s^{2}`
* - :math:`g`
- Gravitational constant
- :math:`m / s^{2}`
* - :math:`G`
- Mass flux
- :math:`kg / m^{2} - s`
* - :math:`G_{2}`
- Orifice coefficient
-
* - :math:`h`
- Specific enthalpy
- :math:`J / kg`
* - :math:`hp`
- Primary side heat transfer coefficient in the simple heater model
- :math:`W / m^{2} - K`
* - :math:`h_{tot}, H`
- Total heat transfer coefficient
- :math:`W / m^{2} - K`
* - :math:`H`
- Height
- :math:`m`
* - :math:`H`
- Work
- :math:`W`
* - :math:`I`
- Moment of inertia
- :math:`kg - m^{2}`
* - :math:`j`
- Lowermost node in a region
-
* - :math:`k`
- Thermal conductivity
- :math:`W / m - K`
* - :math:`k`
- Valve spring constant
- :math:`kg / s^{2}`
* - :math:`k_{p}`
- Thermal conductivity of the primary side in the simple heater model
- :math:`W / m - K`
* - :math:`K`
- Loss constant
-
* - :math:`L`
- Element length, or distance
- :math:`m`
* - :math:`L_{B} / D_{B}`
- Effective length-to-diameter ratio per bend
-
* - :math:`m, M`
- Mass
- :math:`kg`
* - :math:`n`
- Index on the discretized time variable
-
* - :math:`n`
- Number of nodes in a region
-
* - :math:`N_{B}`
- Number of bends along a flow path
-
* - :math:`Nu`
- Nusselt number
-
* - :math:`P,\ P^{*}`
- Pressure
- :math:`Pa`
* - :math:`POD`
- Pitch-to-diameter ratio
-
* - :math:`Pr`
- Prandtl number
-
* - :math:`q`
- Heat flux
- :math:`J / s - m^{2}`
* - :math:`Q`
- Heat source
- :math:`J / s`
* - :math:`Q`
- Volumetric heat source
- :math:`W / m^{3}`
* - :math:`Q`
- Energy transfer rate
- :math:`W`
* - :math:`r`
- Radius
- :math:`m`
* - :math:`r_{5}`
- Two-phase multiplier
-
* - :math:`R`
- Thermal resistance
- :math:`K / W`
* - :math:`R`
- Loss factor
-
* - :math:`Re`
- Reynolds number
-
* - :math:`s`
- Distance
- :math:`m`
* - :math:`s`
- Specific entropy
- :math:`J / kg - K`
* - :math:`sgn \left( j, l \right)`
- | +1 if the steady state flow in segment :math:`j` is entering volume :math:`l`
| -1 if the steady state flow in segment :math:`j` is leaving volume :math:`l`
-
* - :math:`t`
- Time
- :math:`s`
* - :math:`T`
- Temperature
- :math:`K`
* - :math:`TP`
- Elevation of two-phase interface
- :math:`m`
* - :math:`u, v`
- Fluid velocity
- :math:`m / s`
* - :math:`U_{pseu}`
- Pseudo-heat conduction coefficient
- :math:`W / K`
* - :math:`v`
- Specific volume
- :math:`m^{3} / kg`
* - :math:`V`
- Volume
- :math:`m^{3}`
* - :math:`V_{a},V_{b}`
- Steam velocities relative to the blade and parallel to the blade motion at the blade entrance and exit, respectively
- :math:`m / s`
* - :math:`V_{1}`
- Absolute steam velocity at the blade entrance
- :math:`m / s`
* - :math:`V_{2}`
- Steam velocity relative to the blade at the blade entrance
- :math:`m / s`
* - :math:`V_{3}`
- Steam velocity relative to the blade at the blade exit
- :math:`m / s`
* - :math:`V_{4}`
- Absolute steam velocity at the blade exit
- :math:`m / s`
* - :math:`w`
- Mass flow rate
- :math:`kg / s`
* - :math:`WR`
- Wall resistance on water side
-
* - :math:`WRNA`
- Wall resistance on sodium side
-
* - :math:`x`
- Quality
-
* - :math:`y`
- Valve stem position
- :math:`m`
* - :math:`z`
- Spatial variable
- :math:`m`
* - :math:`Z`
- Spatial location, region length, or elevation of pipe center
- :math:`m`
* - :math:`\Delta z`
- :math:`z_{0} - \ z_{I}`, the elevation difference between the outlet and the inlet of a flow element
- :math:`m`
* - :math:`\alpha`
- Void fraction
-
* - :math:`\alpha`
- Nozzle exit angle
- :math:`rad`
* - :math:`\beta`
- Volumetric quality
-
* - :math:`\gamma`
- Blade exit angle
- :math:`rad`
* - :math:`\delta`
- Thickness
- :math:`m`
* - :math:`\varepsilon`
- Element roughness
- :math:`m`
* - :math:`\eta`
- Efficiency
-
* - :math:`\theta`
- Angle of inclination with respect to the vertical
-
* - :math:`\mu`
- Dynamic viscosity
- :math:`Pa - s`
* - :math:`v`
- Specific volume
- :math:`m^{3} / kg`
* - :math:`\rho`
- Density
- :math:`kg / m^{3}`
* - :math:`\tau`
- Viscous stress tensor
- :math:`Pa`
* - :math:`\tau`
- Torque
- :math:`N - m`
* - :math:`\varphi`
- Valve characteristic
-
* - :math:`\chi`
- Quality
-
* - :math:`\omega`
- Rotor angular velocity
- :math:`rad / s`
* -
-
-
* - **Subscripts**
-
-
* - :math:`ACC`
- Accumulated pressure at which value fully opens
-
* - :math:`b`
- Bottom
-
* - :math:`B`
- Blade
-
* - :math:`BLD`
- Blowdown pressure at which valve closes
-
* - :math:`D`
- Drain, or DNB
-
* - :math:`E`
- Exhaust
-
* - :math:`f`
- Liquid
-
* - :math:`fg`
- Vapor minus liquid
-
* - :math:`g`
- Vapor
-
* - :math:`G`
- Generator
-
* - :math:`hf`
- Location of hf
-
* - :math:`hg`
- Location of hg
-
* - :math:`i`
- Node number, region number, inside
-
* - :math:`I, in`
- Inlet
-
* - :math:`j`
- Segment number
-
* - :math:`m`
- Metal tube, or tube wall
-
* - :math:`misc`
- Miscellaneous
-
* - :math:`M`
- Moisture, or mid-wall
-
* - :math:`nz`
- Nozzle
-
* - :math:`Na`
- Sodium
-
* - :math:`o`
- Outside, theoretical
-
* - :math:`O,out`
- Outlet
-
* - :math:`r`
- Reference
-
* - :math:`R`
- Rotation
-
* - :math:`s`
- Sodium, shell side, steam drum
-
* - :math:`S`
- Surface
-
* - :math:`sat`
- Saturation
-
* - :math:`SC`
- Subcooled zone
-
* - :math:`SG`
- Steam generator
-
* - :math:`SH`
- Superheated zone
-
* - :math:`t`
- Top, tube side, total
-
* - :math:`T`
- Total, turbine
-
* - :math:`TP`
- Boiling zone
-
* - :math:`u`
- Upper
-
* - :math:`w`
- Water
-
* - :math:`l`
- Volume number
-
* - :math:`\infty`
- Ambient
-
* -
-
-
* - **Superscripts**
-
-
* - :math:`k,n`
- Time step index
-
* - :math:`n`
- Normalized
-
* - :math:`u`
- Unnormalized
-
* - :math:`-`
- Isentropic quantity
-