LiquidMotor Class#
Class to specify characteristics and useful operations for Liquid motors. This class inherits from the Motor class.
- Geometrical attributes
- Motor.coordinate_system_orientation#
Orientation of the motor’s coordinate system. The coordinate system is defined by the motor’s axis of symmetry. The origin of the coordinate system may be placed anywhere along such axis, such as at the nozzle area, and must be kept the same for all other positions specified. Options are “nozzle_to_combustion_chamber” and “combustion_chamber_to_nozzle”.
- Type:
str
- Motor.nozzle_radius#
Radius of motor nozzle outlet in meters.
- Type:
float
- Motor.nozzle_position#
Motor’s nozzle outlet position in meters, specified in the motor’s coordinate system. See Motor.coordinate_system_orientation for more information.
- Type:
float
- Motor.positioned_tanks#
List containing the motor’s added tanks and their respective positions.
- Type:
list
- Mass and moment of inertia attributes
- Motor.dry_mass#
The total mass of the motor structure, including chambers and tanks, when it is empty and does not contain any propellant.
- Type:
float
- Motor.propellant_initial_mass#
Total propellant initial mass in kg, includes fuel and oxidizer.
- Type:
float
- Motor.total_mass#
Total motor mass in kg as a function of time, defined as the sum of propellant and dry mass.
- Type:
- Motor.propellant_mass#
Total propellant mass in kg as a function of time, includes fuel and oxidizer.
- Type:
- Motor.total_mass_flow_rate#
Time derivative of propellant total mass in kg/s as a function of time as obtained by the tanks mass flow.
- Type:
- Motor.center_of_mass#
Position of the motor center of mass in meters as a function of time. See Motor.coordinate_system_orientation for more information regarding the motor’s coordinate system.
- Type:
- Motor.center_of_propellant_mass#
Position of the motor propellant center of mass in meters as a function of time. See Motor.coordinate_system_orientation for more information regarding the motor’s coordinate system.
- Type:
- Motor.I_11#
Component of the motor’s inertia tensor relative to the e_1 axis in kg*m^2, as a function of time. The e_1 axis is the direction perpendicular to the motor body axis of symmetry, centered at the instantaneous motor center of mass.
- Type:
- Motor.I_22#
Component of the motor’s inertia tensor relative to the e_2 axis in kg*m^2, as a function of time. The e_2 axis is the direction perpendicular to the motor body axis of symmetry, centered at the instantaneous motor center of mass. Numerically equivalent to I_11 due to symmetry.
- Type:
- Motor.I_33#
Component of the motor’s inertia tensor relative to the e_3 axis in kg*m^2, as a function of time. The e_3 axis is the direction of the motor body axis of symmetry, centered at the instantaneous motor center of mass.
- Type:
- Motor.I_12#
Component of the motor’s inertia tensor relative to the e_1 and e_2 axes in kg*m^2, as a function of time. See Motor.I_11 and Motor.I_22 for more information.
- Type:
- Motor.I_13#
Component of the motor’s inertia tensor relative to the e_1 and e_3 axes in kg*m^2, as a function of time. See Motor.I_11 and Motor.I_33 for more information.
- Type:
- Motor.I_23#
Component of the motor’s inertia tensor relative to the e_2 and e_3 axes in kg*m^2, as a function of time. See Motor.I_22 and Motor.I_33 for more information.
- Type:
- Motor.propellant_I_11#
Component of the propellant inertia tensor relative to the e_1 axis in kg*m^2, as a function of time. The e_1 axis is the direction perpendicular to the motor body axis of symmetry, centered at the instantaneous propellant center of mass.
- Type:
- Motor.propellant_I_22#
Component of the propellant inertia tensor relative to the e_2 axis in kg*m^2, as a function of time. The e_2 axis is the direction perpendicular to the motor body axis of symmetry, centered at the instantaneous propellant center of mass. Numerically equivalent to propellant_I_11 due to symmetry.
- Type:
- Motor.propellant_I_33#
Component of the propellant inertia tensor relative to the e_3 axis in kg*m^2, as a function of time. The e_3 axis is the direction of the motor body axis of symmetry, centered at the instantaneous propellant center of mass.
- Type:
- Motor.propellant_I_12#
Component of the propellant inertia tensor relative to the e_1 and e_2 axes in kg*m^2, as a function of time. See Motor.propellant_I_11 and Motor.propellant_I_22 for more information.
- Type:
- Motor.propellant_I_13#
Component of the propellant inertia tensor relative to the e_1 and e_3 axes in kg*m^2, as a function of time. See Motor.propellant_I_11 and Motor.propellant_I_33 for more information.
- Type:
- Motor.propellant_I_23#
Component of the propellant inertia tensor relative to the e_2 and e_3 axes in kg*m^2, as a function of time. See Motor.propellant_I_22 and Motor.propellant_I_33 for more information.
- Type:
- Thrust and burn attributes
- Motor.total_impulse#
Total impulse of the thrust curve in N*s.
- Type:
float
- Motor.max_thrust#
Maximum thrust value of the given thrust curve, in N.
- Type:
float
- Motor.max_thrust_time#
Time, in seconds, in which the maximum thrust value is achieved.
- Type:
float
- Motor.average_thrust#
Average thrust of the motor, given in N.
- Type:
float
- Motor.burn_time#
Tuple containing the initial and final time of the motor’s burn time in seconds.
- Type:
tuple of float
- Motor.burn_start_time#
Motor burn start time, in seconds.
- Type:
float
- Motor.burn_out_time#
Motor burn out time, in seconds.
- Type:
float
- Motor.burn_duration#
Total motor burn duration, in seconds. It is the difference between the burn_out_time and the burn_start_time.
- Type:
float