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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 397 records · Page 22
All sourcesNASA NTRSDOE OSTI
NASA NTRS1978

Space Shuttle SRM Ignition System

This paper presents the Space Shuttle SRM Ignition System, which consists of a large solid propellant main igniter, a small solid propellant initiating igniter and an electromechanical safety and arming device containing two NASA Standard Initiators and a B-KNO3 pyrotechnic booster charge. In development motors, the igniter also has a valve through which CO2 is injected for post-firing quench of the SRM. The igniter has redundant, testable seals at all pressurized joints and three major reusable components; the case, the adapter, and the S&A device. Two development problem areas are discussed. One problem area was transverse mode combustion instability in the main igniter with maximum amplitude of 340 psi peak-to-peak at a frequency of 1500 Hz, which was reduced by a propellant grain configuration change and a change from a 2% aluminum content propellant to a formulation containing 10% aluminum. The other problem area was an excessively rapid rise of thrust in the SRM, which was reduced by reducing the igniter mass flow rate. This mass flow rate reduction was accomplished by removing portions of the grain starpoints in the head end.

Bolieau, C. W.↗
NASA NTRS2002

Portable propellant cutting assembly, and method of cutting propellant with assembly

A propellant cutting assembly and method of using the assembly to cut samples of solid propellant in a repeatable and consistent manner is disclosed. The cutting assembly utilizes two parallel extension beams which are shorter than the diameter of a central bore of an annular solid propellant grain and can be loaded into the central bore. The assembly is equipped with retaining heads at its respective ends and an adjustment mechanism to position and wedge the assembly within the central bore. One end of the assembly is equipped with a cutting blade apparatus which can be extended beyond the end of the extension beams to cut into the solid propellant.

Sharp, Roger A.↗
NASA NTRS1975

Solid rocket technology advancements for space tug and IUS applications

In order for the shuttle tug or interim upper stage (IUS) to capture all the missions in the current mission model for the tug and the IUS, an auxiliary or kick stage, using a solid propellant rocket motor, is required. Two solid propellant rocket motor technology concepts are described. One concept, called the 'advanced propulsion module' motor, is an 1800-kg, high-mass-fraction motor, which is single-burn and contains Class 2 propellent. The other concept, called the high energy upper stage restartable solid, is a two-burn (stop-restartable on command) motor which at present contains 1400 kg of Class 7 propellant. The details and status of the motor design and component and motor test results to date are presented, along with the schedule for future work.

Ascher, W.↗
NASA NTRS1989

The effect of solidity on propeller normal force

Propeller normal force is a major contributor to pitch and yaw stability on propeller driven aircraft. While it is well known that propeller normal force is a function of the number of blades, there are no published data for the high numbers of blades that are used in the new designs such as the UDF. This paper presents the results of a test conducted in the NASA Langley 14- x 22-foot Subsonic Tunnel using a sting-mounted counter-rotation propeller and nacelle. The configurations tested were combinations of 0, 4, and 8 blades per hub. Tests were conducted for blade angle settings of 31.34, 36.34, and 41.34 deg over an angle-of-attack range from -10 to 90 deg and over a range of advance ratios from 0.8 to 1.4. The results show that propeller normal force varies with both solidity and angle of attack.

Dunham, Dana Morris↗
NASA NTRS1994

31st JANNAF Combustion Subcommittee Meeting

This volume, the second of four volumes, is a collection of 36 unclassified/unlimited papers which were presented at the 31st Joint Army-Navy-NASA-Air Force (JANNAF) Combustion Subcommittee Meeting in conjunction with the Exhaust Plume Technology Subcommittee and SPIRITS User Group Meeting held 17-21 October 1994 at the Lockheed Missiles and Space Company, Sunnyvale, California. Specific subjects discussed include solid propellant combustion instability and unsteady combustion, rocket motors, guns and marine combustion characteristics, solid propellant formulation and solid and gas phase combustion kinetics.

Gannaway, Mary T.↗
NASA NTRS1968

Processing and manufacture of composite propellants

This paper is a chemical engineering unit processing treatment of the steps involved in the manufacture of solid propellant motors. The author treats the major processes of raw material preparation, mixing, casting and curing by describing equipment, the processing, steps and some engineering considerations associated therewith. The three simultaneous processes occurring within the solid propellant nixing, namely, homogenization, wetting and curing, are discussed in more detail, briefly touching on control of these reactions and the engineering trade-offs among them.

J F Tormey↗
NASA NTRS1947

The Effect of High Solidity on Propeller Characteristics at High Forward Speeds from Wind-Tunnel Tests of the NACA 4-(3)(06.3)-06 and NACA 4-(3)(06.4)-09 Two-Blade Propellers

Tests of two-blade propellers having the NACA 4-(3)(06.3)-06 and NACA 4-(3)(06.4)-09 blade designs (blade activity factors of 179 and 263, respectively) have been made in the Langley 8-foot high-speed tunnel through a range of blade angle from 20 degrees to 70 degrees for free-stream Mach numbers from 0.165 to 0.725 to determine the effects of high solidity and compressibility on propeller characteristics. The tests are part of a general investigation of propellers at high forward speeds. Results previously reported for similar tests of two-blade propellers having the NACA 4-308-03 and NACA 4-308-045 blade designs (blade activity factors of 87 and 133, respectively) are included for comparison. The results showed that the 0.06- and 0.09-solidity blades, although producing efficiencies of the order of 90 percent, were less efficient than blades of conventional solidity. The variation in average blade lift coefficient with solidity at a constant blade angle and advance-diameter ratio through the speed range of these tests was found to be analogous to the variation of wing lift coefficient with aspect ratio, indicating that high-solidity blades may be desirable at very high speeds. Because of power limitations of the test equipment, conclusive evidence of the possible favorable effects of increased blade solidity at high speeds was not obtained. Further tests are desirable.

Delano, James B.↗
NASA NTRS1986

Vortex shedding from solid rocket propellant inhibitors

Vortex shedding frequency caused by the protrusion of inhibitors into the flow field of a solid rocket motor is investigated by experimental and mathematical models. The time dependent Navier-Stokes equations are solved using a finite difference technique assuming incompressible, two-dimensional flow under both laminar and turbulent flow conditions. For laminar flow, explicit solutions are obtained using a vorticity-transport equation in place of the Navier-Stokes equations. For turbulent flow, a two-equation (k-epsilon) model is used for turbulent modeling and the SIMPLE algorithm is employed as the computational scheme. Cold flow tests were conducted to confirm the basic flow structure and to determine the vortex shedding frequency under both laminar and turbulent flow conditions. The vortex shedding frequencies were determined using a stroboscope to measure the oscillating frequency of yarn tufts which were fastened to one inhibitor in the models. A hot-film anemometer established the velocity history behind the inhibitor. Good agreement between the theoretical results and measurements of the vortex shedding frequencies is demonstrated.

Shu, P. H.↗
NASA NTRS1979

Seismic vibration source

A system for vibrating the earth in a location where seismic mapping is to take place is described. A relatively shallow hole formed in the earth, such as a hole 10 feet deep, placing a solid propellant in the hole, sealing a portion of the hole above the solid propellant with a device that can rapidly open and close to allow a repeatedly interrupted escape of gas. The propellant is ignited so that high pressure gas is created which escapes in pulses to vibrate the earth.

Dowler, W. L.↗
NASA NTRS1981

Viscoelastic propellant effects on Space Shuttle Dynamics

The program of solid propellant research performed in support of the space shuttle dynamics modeling effort is described. Stiffness, damping, and compressibility of the propellant and the effects of many variables on these properties are discussed. The relationship between the propellant and solid rocket booster dynamics during liftoff and boost flight conditions and the effects of booster vibration and propellant stiffness on free free solid rocket booster modes are described. Coupled modes of the shuttle system and the effect of propellant stiffness on the interfaces of the booster and the external tank are described. A finite shell model of the solid rocket booster was developed.

Bugg, F.↗
NASA NTRS1973

The Delta launch vehicle Model 2914 series

Description of a new, medium-class Delta launch-vehicle configuration, the three-stage Model 2914. The first stage of this vehicle is composed of a liquid-propellant core which is thrust-augmented with up to nine strap-on solid-propellant motors. The second stage, recently uprated with a strap-down inertial guidance system, is now being modified to adapt the liquid-propellant descent engine from the Apollo Lunar Excursion Module. The third stage is a spin-stabilized solid-propellant motor. The Model 2914 is capable of injecting 2040 kg into low earth orbit, 705 kg into geosynchronous transfer orbit, or 455 kg into an escape trajectory.

Gunn, C. R.↗
NASA NTRS1972

Study of solid rocket motor for space, shuttle booster, volume 2, book 4 appendices B thru D

The mass properties and related data for the solid propellant rocket engine for use with the space shuttle are presented. Data for three solid propellant rocket engines are provided. The three designs considered are: (1) baseline parallel burn, (2) optional parallel burn, and (3) baseline series burn. Layouts of the respective designs to show design and dimensional data are included.

Source record↗
NASA NTRS1980

Experimental determination of the admittances of aluminized propellants by the impedance tube method

The adaptation of the impedance tube concept for the determination of the pressure coupled admittances and response functions of burning solid propellants is discussed. The results obtained in experiments with UTP-3001 and UTP-19360 aluminized propellants are presented. It is shown that the admittance Y remains constant during the quasi-steady burn period of a test, indicating constant driving of the gas phase disturbance by the burning solid propellant. The measured real part of the admittance is positive, indicating that the burning aluminized propellant is driving the gas phase oscillations. In addition, the measured high gas phase damping, provided by the aluminum oxide particles in the gas phase, suggests that the latter can significantly increase the damping in unstable solid rockets over the investigated frequency range. Finally, it is shown that the wave structure obtained by numerically solving the impedance tube wave equations which utilize the determined propellant admittance as an initial condition and the determined value of G to describe the gas phase losses is in excellent agreement with the measured wave structure.

Baum, J. D.↗
NASA NTRS1995

Environmentally compatible solid rocket propellants

Hercules' clean propellant development research is exploring three major types of clean propellant: (1) chloride-free formulations (no chlorine containing ingredients), being developed on the Clean Propellant Development and Demonstration (CPDD) contract sponsored by Phillips Laboratory, Edwards Air Force Base, CA; (2) low HCl scavenged formulations (HCl-scavenger added to propellant oxidized with ammonium perchlorate (AP)); and (3) low HCl formulations oxidized with a combination of AN and AP (with or without an HCl scavenger) to provide a significant reduction (relative to current solid rocket boosters) in exhaust HCl. These propellants provide performance approaching that of current systems, with less than 2 percent HCl in the exhaust, a significant reduction (greater than or equal to 70 percent) in exhaust HCl levels. Excellent processing, safety, and mechanical properties were achieved using only readily available, low cost ingredients. Two formulations, a sodium nitrate (NaNO3) scavenged HTPB and a chloride-free hydroxy terminated polyether (HTPE) propellant, were characterized for ballistic, mechanical, and rheological properties. In addition, the hazards properties were demonstrated to provide two families of class 1.3, 'zero-card' propellants. Further characterization is planned which includes demonstration of ballistic tailorability in subscale (one to 70 pound) motors over the range of burn rates required for retrofit into current Hercules space booster designs (Titan 4 SRMU and Delta 2 GEM).

Jacox, James L.↗