Engineering topics
Explore propulsion reports from NASA NTRS and DOE OSTI. Search rocket engines, electric propulsion and thrusters; verify designs and performance in the source documents.
Multiple rocket engine exhaust plumes calculated by method of characteristics and finite difference and compared with schlieren data
NASA is developing technologies to prepare for human exploration missions to Mars. Solar electric propulsion (SEP) systems are expected to enable a new cost effective means to deliver cargo to the Mars surface. Nearer term missions to Mars moons or near-Earth asteroids can be used to both develop and demonstrate the needed technology for these future Mars missions while demonstrating new capabilities in their own right. This presentation discusses recent technology development accomplishments for high power, high voltage solar arrays and power management that enable a new class of SEP missions.
To assess ‘quick’ missions to Mars, a study was performed to determine the feasibility of a two-year roundtrip class mission concept of operation that enables boots on Mars in the 2030s. After performing a Phase 1.1 2036 Mars opposition design case, the more difficult 2039 opposition design was pursued. This Phase 1.2 also sought to further refine the concept, building on feasibility, and addressing several challenges brought by independent team reviews. Given the date of 2039, nearer-term technologies, primarily nuclear thermal and nuclear electric were deemed as the most viable for these missions. This paper explores a nuclear electric and chemical combined propulsion approach to achieve the desired mission timeline.
The number of small unmanned aerial vehicles (UAVs) used for private and commercial applications is growing exponentially, beyond the domain of hobby enthusiasts. However, standards development has not been keeping up with the applications and technologies now available. The advent of inexpensive battery-powered quadcopters as stable aerial photography and remote-viewing platforms has expanded the utility of these systems into commercial and private applications for inspection and surveillance. With drone-delivered packages on the horizon, the potential for expansion will be even higher. These developments need to be incorporated into standards being produced for UAVs and propulsion systems.
In the pulsed plasma rocket (PPR) reactor, neutron induced fission processes are utilized to implement a series of pulsed micro-explosions of very high power and eject plasma as a propellant. More specifically, projectiles (bullets) composed of moderated uranium are sent through the chamber of an unmoderated uranium barrel. By inducing rapid fission within the bullets, a plasma can be generated with appropriate delivery of neutrons. This study aims to assess the neutronics performance of the PPR reactor during normal operations using the MOOSE-based Rattlesnake code through the evaluation of the impact of the movement of the fuel bullet and the rotation of control drums on the criticality of the system. The Monte Carlo (MC) code Serpent 2 was employed to generate material-based cross sections for use in Rattlesnake and the reference neutronics solution. Cubit was used to generate the mesh for the Rattlesnake model. Parametric studies were conducted to evaluate the best approaches for cross section and mesh generation to ensure accurate results from Rattlesnake. As part of the verification process, the eigenvalue results of the system at various fuel bullet positions were obtained using Rattlesnake and compared with the reference solutions. The acceptable differences show that the Rattlesnake model with appropriate cross section and mesh generation procedure is a sufficiently accurate approximation of the continuous energy (CE) MC model for micro-sized reactors like the PPR reactor. Next, the impact of the rotation of the control drums on the system criticality was evaluated using the verified model. It was shown that the high-fidelity simulation using the deterministic code Rattlesnake can produce sufficiently accurate results for the evaluation of the reactor's neutronics performance in different phases of the normal operation with acceptable computational cost.
Rocket performance and size of electron bombardment ion source
Application of field-ion emission to electrostatic rocket engines - ionization lifetimes of hydrogen, lithium, sodium, rubidium, cesium, and xenon
Utilization of a permanent magnet circuit in an electron-bombardment ion rocket
Electron bombardment ion rocket with a permanent magnet circuit described
Permanent magnetic circuit for low current density electron bombardment ion rocket engine
Electrode arcing effects on ion rocket thrustor system design
Nuclear-electric power requirements for electric rockets - contact and bombardment ion engines, arc jets, and pulsed plasma engines
Performance of ion rocket thrust augmentor, Langmuir probe measurements, secondary electron emission from porous tungsten, and heat transfer from large diameter Pirani pressure gauges
Eight-stage bleed-type turbine for hydrogen propelled nuclear rocket applications - design of turbine and experimental performance of first two stages
Perturbation solutions of differential equations of motion for low-thrust rocket trajectories
Heat sterilizability of liquid hydrazine propulsion system
Transient and steady performance of ion rocket thrust augmentor