proptools.turbopump module

Nozzle flow calculations.

Matt Vernacchia proptools 2016 Apr 3

proptools.turbopump.dp2head(dp, rho)

Convert pump pressure rise to US-units head.

Parameters:
  • dp – Pump pressure rise [units: pascal].
  • rho – density [units: kilogram meter**-3].
Returns:

feet].
Return type:

pump head [units
proptools.turbopump.gg_dump_isp(p_o, p_te, p_ne, T_o, eta, gamma, c_p, m_molar)

Get the specific impulse of a Gas Generator turbine exhaust dump.

Parameters:
  • p_o – turbine inlet stagnation pressure [units: pascal].
  • p_te – turbine exit pressure [units: pascal].
  • p_ne – Dump nozzle exit pressure [units: pascal].
  • T_o – turbine inlet stagnation temperature [units: kelvin].
  • eta – turbine efficiency.
  • gamma – working gas ratio of specific heats [units: none].
  • c_p – working gas heat capacity at const pressure [units: joule kilogram**-1 kelvin**-1].
  • m_molar – working gas molar mass [units: kilogram mole**-1].
proptools.turbopump.gpm2m_dot(gpm, rho)

Convert gallons per minute to mass flow.

Parameters:
  • gpm – Volume flow [gallon minute**-1].
  • rho – density [units: kilogram meter**-3].
Returns:

mass flow [units: kilogram second**-1].
Return type:

m_dot
proptools.turbopump.m_dot2gpm(m_dot, rho)

Convert mass flow to gallons per minute.

Parameters:
  • m_dot – mass flow [units: kilogram second**-1].
  • rho – density [units: kilogram meter**-3].
Returns:

Volume flow [gallon minute**-1].
proptools.turbopump.pump_efficiency(dp, m_dot, rho, N)

Pump efficiency estimate.

Based on figure 6-23 in Huzel and Huang.

Parameters:
  • dp – Pump pressure rise [units: pascal].
  • m_dot – Pump mass flow [units: kilogram second**-1].
  • rho – Density of pumped fluid [units: kilogram meter**-3].
  • N – Pump rotation speed [radian second**-1].
Returns:

none].
Return type:

pump efficiency [units
proptools.turbopump.pump_efficiency_demo()
proptools.turbopump.pump_power(dp, m_dot, rho, eta)

Get the input drive power for a pump.

Parameters:
  • dp – Pump pressure rise [units: pascal].
  • m_dot – Pump mass flow [units: kilogram second**-1].
  • rho – Density of pumped fluid [units: kilogram meter**-3].
  • eta – Pump efficiency [units: none].
Returns:

watt].
Return type:

The shaft power required to drive the pump [units
proptools.turbopump.pump_specific_speed_us(dp, m_dot, rho, N)

Pump specific speed N_s in US units.

Parameters:
  • dp – Pump pressure rise [units: pascal].
  • m_dot – Pump mass flow [units: kilogram second**-1].
  • rho – Density of pumped fluid [units: kilogram meter**-3].
  • N – Pump rotation speed [radian second**-1].
Returns:

rpm gallon**0.5 minute**-0.5 feet**-0.75)].
Return type:

N_s [units
proptools.turbopump.radsec2rpm(radsec)

Convert radian second**-1 to rpm.

proptools.turbopump.rpm2radsec(rpm)

Convert rpm to radian second**-1.

proptools.turbopump.ssi_turbine_efficiency(uco)

Efficiency of a single-stage impulse turbine.

Data from 10-9 in Rocket Propulsion Elements.

Parameters:uco – Velocity ratio u / c_o [units: none].
Returns:none].
Return type:turbine efficiency [units
proptools.turbopump.trubine_power(p_o, p_e, m_dot, T_o, eta, gamma, c_p)

Get the output drive power for a turbine.

Parameters:
  • p_o – Turbine inlet stagnation pressure [units: same as p_e].
  • p_e – Turbine exit pressure [units: same as p_o].
  • m_dot – Turbine working gas mass flow [units: kilogram second**-1].
  • T_o – Turbine inlet stagnation temperature [units: kelvin].
  • gamma – Turbine working gas ratio of specific heats [units: none].
  • c_p – working gas heat capacity at const pressure [units: joule kilogram**-1 kelvin**-1].
Returns:

watt].
Return type:

The shaft power produced by the turbine [units
proptools.turbopump.turbine_efficiency_demo()
proptools.turbopump.turbine_enthalpy(p_o, p_e, T_o, gamma, c_p)

Get the specific enthalpy drop for a turbine.

Parameters:
  • p_o – Turbine inlet stagnation pressure [units: same as p_e].
  • p_e – Turbine exit pressure [units: same as p_o].
  • T_o – Turbine inlet stagnation temperature [units: kelvin].
  • gamma – Turbine working gas ratio of specific heats [units: none].
  • c_p – working gas heat capacity at const pressure [units: joule kilogram**-1 kelvin**-1].
Returns:

joule kilogram**-1].
Return type:

The specific enthalpy drop across the turbine [units
proptools.turbopump.turbine_exit_temperature(p_o, p_te, T_o, eta, gamma, c_p)

Get the turbine exit temperature.

Parameters:
  • p_o – turbine inlet stagnation pressure [units: pascal].
  • p_te – turbine exit pressure [units: pascal].
  • T_o – turbine inlet stagnation temperature [units: kelvin].
  • eta – turbine efficiency.
  • gamma – working gas ratio of specific heats [units: none].
  • c_p – working gas heat capacity at const pressure [units: joule kilogram**-1 kelvin**-1].
proptools.turbopump.turbine_spout_velocity(p_o, p_e, T_o, gamma, c_p)

Get the theoretical spouting velocity for a turbine.

Parameters:
  • p_o – Turbine inlet stagnation pressure [units: same as p_e].
  • p_e – Turbine exit pressure [units: same as p_o].
  • T_o – Turbine inlet stagnation temperature [units: kelvin].
  • gamma – Turbine working gas ratio of specific heats [units: none].
  • c_p – working gas heat capacity at const pressure [units: joule kilogram**-1 kelvin**-1].
Returns:

mater second**-1].
Return type:

The theoretical spouting velocity c_o of the turbine [units