.ThermofluidStream.Processes.Internal.FlowResistance.laminarTurbulentPressureLoss

Information

Pressure loss after after Darcy–Weisbach, which is valid in laminar and turbulent flow regimes.

In order to avoid a 0^0 for Re=0 (and therefore a = 1) in the computation of lambda_aux, we add epsilon=0.01 to Re to lower bound it in a smooth way.

ks_input defines the pipe roughness. It can be selected from a list of materials or given directly.

Cheng, Nian-Sheng (2008). Formulas for friction factor in transitional regimes. In:Journal of Hydraulic Engineering134.9, pp. 1357-1362

Elmqvist, Hilding, Hubertus Tummescheit, and Martin Otter (2003). Object-orientedmodeling of thermo-fluid systems. In:3rd International Modelica Conference,pp. 269-286.

Interface

function laminarTurbulentPressureLoss
  extends Internal.FlowResistance.partialPressureLoss;
  import Modelica.Constants.pi;
  input SI.Length ks_input(min = 1e-7) = 1e-7 "Pipe roughness" annotation(
    Dialog(enable = (material == ThermofluidStream.Processes.Internal.Material.other)));
  input ThermofluidStream.Processes.Internal.Material material = ThermofluidStream.Processes.Internal.Material.other "Material of pipe" annotation(
    Dialog(enable = true));
end laminarTurbulentPressureLoss;