modelGnielinski2010
Pipe correlation of Gnielinski 2010
Extends from GnielinskiHeatTransfer (Recip heat transfer based on Gnielinski pipe equation).
Information
Reference:
In 2013, Irimescu adapted an older equation by Gnielinski for SI and CI engines. Note that this implementation contains a simplified version using only the piston speed as characteristic velocity whereas the paper by Irimescu proposes a turbulence-based approach for this purpose.
- (Irimescu2013)
- Irimescu, A.
- Convective heat transfer equation for turbulent flow in tubes applied to internal combustion engines operated under motored conditions
- Applied Thermal Engineering, 2013, Vol. 50(1), pp. 536-545
- (Gnielinski1976)
- Gnielinski, V.
- New Equations For Heat And Mass-transfer In Turbulent Pipe And Channel Flow
- International Chemical Engineering, 1976, Vol. 16(2), pp. 359-368
Implementation:
2013 for Technical University of Denmark, DTU Mechanical Engineering, Kongens Lyngby, Denmark by Jorrit Wronski (jowr@mek.dtu.dk)
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Integer | initialize (from PartialCylinderHeatTransfer) | 2 | 0: None, 1: High HTC, 2: Low HTC |
| Real | sigma | 0.14 | Correction exponent |
| Internal Interface | |||
| Integer | n (from PartialHeatTransfer) | 1 | Number of heat transfer segments |
| Boolean | use_k (from PartialHeatTransfer) | false | = true to use k value for thermal isolation |
| Ambient | |||
| SI.CoefficientOfHeatTransfer | k (from PartialHeatTransfer) | 0 | Heat transfer coefficient to ambient |
| SI.Temperature | T_ambient (from PartialHeatTransfer) | system.T_ambient | Ambient temperature |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Fluid.Interfaces.HeatPorts_a | heatPorts (from PartialHeatTransfer) | Heat port to component boundary |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Medium.ThermodynamicState | states (from PartialHeatTransfer) | Thermodynamic states of flow segments | |
| SI.Area | surfaceAreas (from PartialHeatTransfer) | Heat transfer areas | |
| SI.HeatFlowRate | Q_flows (from PartialHeatTransfer) | Heat flow rates | |
| Modelica.Fluid.System | system (from PartialHeatTransfer) | System wide properties | |
| Medium.Temperature | Ts (from PartialHeatTransfer) | Medium.temperature(states) | Temperatures defined by fluid states |
| Modelica.SIunits.Angle | crankshaftAngle (from PartialCylinderHeatTransfer) | ||
| Modelica.SIunits.Area | pistonCrossArea (from PartialCylinderHeatTransfer) | ||
| Modelica.SIunits.Length | strokeLength (from PartialCylinderHeatTransfer) | ||
| Modelica.SIunits.CoefficientOfHeatTransfer | h (from PartialCylinderHeatTransfer) | ||
| Modelica.SIunits.HeatFlux | q_w (from PartialCylinderHeatTransfer) | Heat flux from wall | |
| Modelica.SIunits.Velocity | c_c (from PartialCylinderHeatTransfer) | Current piston speed | |
| Modelica.SIunits.Velocity | c_m (from PartialCylinderHeatTransfer) | Mean piston speed | |
| Modelica.SIunits.Angle | theta (from PartialCylinderHeatTransfer) | Crankshaft angle | |
| Modelica.SIunits.AngularVelocity | omega_c (from PartialCylinderHeatTransfer) | Current angular crank velocity | |
| Modelica.SIunits.AngularVelocity | omega_m (from PartialCylinderHeatTransfer) | Mean angular crank velocity | |
| Modelica.SIunits.Length | bore (from PartialCylinderHeatTransfer) | ||
| Modelica.SIunits.Length | stroke (from PartialCylinderHeatTransfer) | ||
| Modelica.SIunits.Length | position (from PartialCylinderHeatTransfer) | Clearance from cyl. head | |
| Modelica.SIunits.Length | position_m (from PartialCylinderHeatTransfer) | Mean clearance from cyl. head | |
| Real | HTC_gain (from PartialCylinderHeatTransfer) | Amplifier for h[i] | |
| Modelica.SIunits.Length | Gamma (from GnielinskiHeatTransfer) | Characteristic length | |
| Modelica.SIunits.Velocity | Lambda (from GnielinskiHeatTransfer) | Characteristic velocity | |
| Real | xtra (from GnielinskiHeatTransfer) | Reynolds correction factor | |
| Real | zeta (from GnielinskiHeatTransfer) | Friction factor | |
| Real | K (from GnielinskiHeatTransfer) | Correction term | |
| Modelica.SIunits.Length | D (from GnielinskiHeatTransfer) | Pipe diameter | |
| Modelica.SIunits.Length | L (from GnielinskiHeatTransfer) | Pipe length | |
| Modelica.SIunits.ReynoldsNumber | Re (from GnielinskiHeatTransfer) | ||
| Modelica.SIunits.PrandtlNumber | Pr (from GnielinskiHeatTransfer) | ||
| Modelica.SIunits.NusseltNumber | Nu (from GnielinskiHeatTransfer) | ||
| Modelica.SIunits.ThermalConductivity | lambda (from GnielinskiHeatTransfer) | ||
| Modelica.SIunits.DynamicViscosity | eta (from GnielinskiHeatTransfer) | ||
| Modelica.SIunits.SpecificHeatCapacityAtConstantPressure | cp (from GnielinskiHeatTransfer) | ||
| Real | numerator (from GnielinskiHeatTransfer) | ||
| Real | denominator (from GnielinskiHeatTransfer) |