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JSBSim Thrusters: Difference between revisions
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→C_THRUST and C_POWER tables
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The C_THRUST and C_POWER tables are required. | The C_THRUST and C_POWER tables are required. | ||
The independent variable for both tables is Advance Ratio (J). The dependent variable is the coefficient of thrust (Ct) for the C_THRUST and the coefficient of power (Cp) for C_POWER. | The independent variable for both tables is [http://en.wikipedia.org/wiki/Advance_ratio Advance Ratio] (J). The dependent variable is the coefficient of thrust (Ct) for the C_THRUST and the coefficient of power (Cp) for C_POWER. | ||
[http://www.mh-aerotools.de/airfoils/pylonprops_1.htm Propellors for F3D Models explains the theory] and has [http://www.mh-aerotools.de/airfoils/pylonprops_2.htm formulas] and [http://www.mh-aerotools.de/airfoils/pylonprops_3.htm many graphs] showing the relationship between J, Ct, and Cp. | [http://www.mh-aerotools.de/airfoils/pylonprops_1.htm Propellors for F3D Models explains the theory] and has [http://www.mh-aerotools.de/airfoils/pylonprops_2.htm formulas] and [http://www.mh-aerotools.de/airfoils/pylonprops_3.htm many graphs] showing the relationship between J, Ct, and Cp. | ||
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Ct/Cp gives the efficiency (eta), and propeller shape and general design give each propeller a distinctive [http://www.mh-aerotools.de/airfoils/pylonprops_3.htm efficiency curve]. For fixed-pitch propellers, the propeller is generally designed to reach peak efficiency either at climb velocity & RPM, cruise velocity and RPM, or some compromise between the two. [http://en.wikipedia.org/wiki/Controllable_pitch_propeller Variable pitch propellers] and [http://en.wikipedia.org/wiki/Constant_speed_propeller constant speed propellers] bring different factors into play. | Ct/Cp gives the efficiency (eta), and propeller shape and general design give each propeller a distinctive [http://www.mh-aerotools.de/airfoils/pylonprops_3.htm efficiency curve]. For fixed-pitch propellers, the propeller is generally designed to reach peak efficiency either at climb velocity & RPM, cruise velocity and RPM, or some compromise between the two. [http://en.wikipedia.org/wiki/Controllable_pitch_propeller Variable pitch propellers] and [http://en.wikipedia.org/wiki/Constant_speed_propeller constant speed propellers] bring different factors into play. | ||
Note that several of the values mentioned above can be viewed while FG is running, in the property tree under /fdm/jsbsim/propulsion/engine. This is useful for seeing how the settings and tables play out under various conditions and fine-tuning the settings. | |||
==== Sample C_THRUST and C_POWER tables ==== | ==== Sample C_THRUST and C_POWER tables ==== | ||