Turbine4_CL
The function Turbine4_CL(n_s) uses a curve fit to the Balje curve peak to provide the optimal value of specific diameter for a turbine given the specific speed. These curves were developed in:
Sondelski, Becky, Mass Optimization of a Supercritical CO2 Brayton Cycle with a Direct Cooled Nuclear Reactor for Space Surface Power, M.S. Thesis, Dept. of Mechanical Engineering, UW-Madison, (2019).
and are based on the Balje curves presented in Balje, O.E., Turbomachinery, New York, Wiley & Sons, (1981).
The calling protocol is:
Turbine4_CL(n_s)
Inputs:
n_s = specific speed (rad) = omega*sqrt(V_dot)/Dh_s^0.75
Output:
d_s = specific diameter (-) = D*Dh_s^0.25/sqrt(V_dot)
Note that the companion function Turbine3_CL provides the efficiency as a function of specific speed and specific diameter.
Example:
$Load Component Library
n_s=1
d_s=Turbine4_CL(n_s)
eta_max=-999
eta = Turbine3_CL(n_s, d_s, eta_max)
{Solution
d_s = 2.34
eta = 0.6955}