1. Pistonless Dual Chamber Rocket Fuel Pump
Tell them what you going to tell them etc
Steve Harrington, Ph.D.

2. LOX/Jet-A Pressure Fed Design Working Well
What’s Next?… More Altitude!

3. The Problem is Mass Ratio: How to Make a Lightweight, Inexpensive Rocket with a Large Fuel Capacity.
For performance, a rocket must have large, lightweight propellant tanks
Pressure fed tanks are heavy and/or expensive and safety margins cost too much in terms of performance.
Turbopumps require massive engineering effort and are expensive.
The solution is the The Dual Pistonless Pump
Simple to design and manufacture and with performance comparable to a turbopump

4. Outline Discuss basic pump design concept
Introduce latest pump innovations
List pump advantages over turbopump and pressure fed systems.
Present pump test results
Derive calculation of pump thrust to weight ratio which show that a LOX/RP-1 pump has a T/W of over 700

5. First Generation Design:
Drain the main tank at low pressure into a small chamber.
Pressurize the small chamber and feed to the engine.
Run two in parallel, venting and filling one faster than the other is emptied
Animate diagram
More info at: www.
rocketfuelpump.com

6. Second Generation Design:
Main chamber vents and fills quickly through multiple check valves.
One main chamber and one auxiliary chamber, less weight than two chambers of equal size
Pump fits in tank, simplified plumbing
Concentric design maintains balance.
Model has been built and tested (patent pending)
Animate diagram

7. Advantages Much lighter than pressure fed system at similar cost.
At one to two orders of magnitude lower engineering and manufacturing cost than turbopump.
Low weight, comparable to turbopump.
Quick startup, shutdown. No fuel used during spool up.
Can be run dry. No minimum fuel requirement.
Less than 10 moving parts. Inherent reliability.
Inexpensive materials and processes.
Negligible chance of catastrophic failure.
Scalable, allows for redundant systems.

8. Engineering Cost: Dual Pistonless Pump
Check Valves
Level Sensors
Pressure vessels
These parts are available off the shelf
Control System (microprocessor or logic circuit)
Pump model made from industrial/consumer parts
4 MPa, 1.2 kg/sec, 7 kg

9. Engineering cost: Turbopumps
Fluid Dynamics of rotor/stator
Bearings
Seals
Cavitation
Heat transfer
Thermal shock
Rotor dynamics
Startup
Shut down

10. Development Issues
Pressure Spikes in output may require accumulator or valve timing adjustment
Currently uses slightly more gas than pressure fed system. can use less with pressurant heating.
Not invented here.
No experience base, must be static tested and flown.

11. Pump Performance:
Pump performance close to target of 1.5 kg/sec at 4 Mpa
Pressure spikes have been reduced. Requires more development.
Pump chamber vents and pressurizes more quickly when running on Helium
Pump needs to be tested with LN2 and Jet-A
Animate diagram
Pump running on compressed air at room temperature, pumping water.

12. Pistonless Pump Mass Calculation:
Chamber Mass
Spherical Chamber Volume and Diameter
Combine Equations to get Chamber Mass
as a function of
flow rate
Chamber Thickness in terms of fuel pressure and maximum stress

13. Pistonless Pump Thrust to weight Ratio Calculation:
Thrust for Ideal Expansion
Assumptions:
Auxiliary chamber is 1/4 the size of main chamber
Valves and ullage add 25% to mass
Total pump mass is or1.56 times main chamber mass 1/(1.56*1.5)=.43
Pump thrust to weight

14. Typical Pump Thrust/Weight Calculations
Assumptions:
Add graph showing where weight goes.
Rocket Chamber Pressure 4 MPa
Pump cycle time 5 seconds.
Sea level Specific Impulse from Huang and Huzel ,
Pump Chambers are 2219 aluminum, 350 MPa design yield strength, 2.8 specific gravity

15. Conclusions/ Future Plans
Pump weight and cost are low and it works as designed.
Next steps:
Static test and fly pump with Flometric’s rocket technology.
Combine with low cost ablative engines and low cost vehicles for low cost access to space.
NASA
Fastrac
Beal
BA 810
Time is right for this development.
TRW
Low Cost Pintle Engine
Microcosm
Scorpius