Staged Combustion CycleThermodynamics 2 Project

Nelson Ojeda

ME3120-22Presented: October 22, 2015

Prof. Ronaldo Sosa

ME Thermodynamics2

Statement of the Objective

General Objectives Thermodynamically Processes (P-V and T-S Diagrams) Advantages and disadvantages of the cycle Comparison with Carnot cycle Functionalities of the cycle Recent implementation and limitations

Staged Combustion Cycle

ME Thermodynamics 3

Originality Assessment1. Philip Graham, Hill, Carl Peterson; “

Mechanics and Thermodynamics of Propulsion”: Second Edition by Addison- Wesley Publishing (1992): Pages 467-478 & 469- 588 Print.

2. R. Douglas Archer, Maido Saarlas; “An Introduction to Aerospace Propulsion”: Second Edition by Prentice Hall, Inc. (1996): Pages- 28 & 433- 489 Print.

3. “Ideal Carnot Cycle” NASA informational page. Web. 12 Oct. 2015. <https://www.grc.nasa.gov/www/k-12/airplane/carnot.html>

4. “P-V liquid bipropellant description and representation” : Web. 13 Oct. 2015. <http://twt.mpei.ac.ru/TTHB/2/KiSyShe/eng/Chapter10/10-3-Reaction-engine-cycles.html>.

Needed previous knowledge

4

Liquid Propellant Rocket Engines• Propellant- means both fuel (e.g.,

alcohol, kerosene, hydrogen) and oxidizer (e.g., oxygen, nitric acid). – Cryogenic- liquid that is a gas at normal

temperature.

ME Thermodynamics

Propellant Boiling point [ᵒF/K]

Critical Pressure [psi/atm]

Critical Temp. [ᵒF/K]

Handling

Hydrogen -423/20 188/13 -400/33 FlammableAmmonia -28/240 1640/111 270/406 Toxic/

flammable

Oxygen -298/90 737/50 -182/155 GoodFluorine -307/85 800/54 -200/144 Very Toxic,

flammable

5

Liquid Propellant Rocket Engines– Storable liquid - stable over a wide range of

temperatures and pressures, which permits storage in closed containers for a long period of time(many months).

ME Thermodynamics

Propellant Boiling point [ᵒF/K]

Vapor Pressure [atm abs.]

Handling

Ethyl alcohol 173/352 0.8 Toxic/flammable

Hydrazine 235/386 1 Toxic/flammable

Nitrogen tetroxide

70/294 1.4 Toxic

Penta-borane 140/333 0.65 Toxic/Expl. In air

ME Thermodynamics 6

How does it work?

Gas Turbine

Staged Combustion Engine

1

2

3

4

Liquid HydrogenLiquid OxygenFuel rich mixture

7

Thermodynamic Process P-V Diagram

Staged Combustion Cycle

Carnot Cycle

V= c

onst

.

P= const.

Adiabatic expansion

Adiabatic expansion

Qout Qout

Qin

Qin

Adiabatic compression

Isothermalcompression

Isothermalexpansion

Isochoricprocess

ME Thermodynamics

ME Thermodynamics8

Thermodynamic Process T-S Diagram

Carnot CycleStaged Combustion Cycle

Isochoricprocess

P= const.

P= const.Adiabatic expansion Adiabatic

expansion

Isothermalexpansion

Isothermalcompression

Qin Qin

Qout Qout

ME Thermodynamics9

Staged Combustion EngineAdvantages

• All of the engine cycles' gases and heat go through the combustion chamber.• Abundance of power, which permits very high chamber pressures that allow

high expansion ratio nozzles. These nozzles give better efficiencies at low altitude.

• Has a wide application in rocketry and very often in aeronautical engineering.

Disadvantages• Development cost for this cycle is higher because the high pressures

complicate the development process. • Harsh turbine conditions.• High temperature piping required to carry hot gases.• A very complicated feedback and control design.

ME Thermodynamics10

Working ExampleSpace Shuttle Main Engine(SSME)

ME LABORATORY 11

Staged Combustion Engine

Source: NASA/ SSME video

Space Shuttle Main Engine(SSME) sketch

ME Thermodynamics12

Implementation • Integrate Powerhead Demonstration (IPD)

After 35 years without a major redesign, the liquid-fueled rocket engine is getting a facelift, courtesy of a team of engineers from NASA, the Air Force, Pratt & Whitney Rocketdyne, and Aerojet. – full-flow, staged-combustion rocket engine that uses liquid

hydrogen as fuel and liquid oxygen as the oxidizer. – better fuel efficiency– higher thrust-to weight ratios– higher Reliability– 250,000 pounds of thrust (twice the thrust of the Space Shuttle

main rocket engines)

ME LABORATORY 13

ImplementationFull-flow staged combustion

ME Thermodynamics14

Developments

SCE-200 engine

• Semi- cryogenic engine• Fuel- kerosene (RP-1)• Oxidizer- liquid oxygen• 460,000 pounds of thrustIn vacuum• Dry weight( 6,000lb)

ME Thermodynamics 15

Developments

RS-25 engine

• Cryogenic engine• Fuel- liquid hydrogen• Oxidizer- liquid oxygen• Configuration for a 70-metric-ton (77-ton)

lift capacity (targeted 130 metric tons (143 ton for the future))

• From 491,000 pounds of trust in vacuum to 510,000

• 1,500 gal/s

Source: NASA/ SSME video

ME Thermodynamics16

Test EnvironmentA-1 Test Stand at NASA’s Stennis Space Center

ME Thermodynamics 17

Questions

18

XCOR Aerospace(Piston Engine)

ME Thermodynamics

ME Thermodynamics19

Most Powerful Single Chamber

ME LABORATORY 20

Most Powerful(4 Chambers)

RD170

• 1773000 pounds of thrust in vacuum