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Showing 1 to 20 of 21 for “"Chemical Propulsion"”.
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Lunar Robotic Precursor Missions Using Electric Propulsion
… study is carried out for the design of electric propulsion based lunar robotic precursor missions. The focus is to understand the relationships between payload mass delivered, electric propulsion power, and trip time. The results are compared against a baseline system using chemical propulsion …
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The design and feasibility of a 10 mN chemical space propulsion thruster
… discusses the design of a ten milli Newton chemical propulsion system for providing approximately 200 m/s delta velocity to a five kg satellite. The nozzle is the focus of the experimental work, which involves building and testing ten 20x upscale 2D nozzles. The ten nozzles involve three …
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Assessing General Propulsion Architectures for Fast Transit Times to Mars for Crewed Missions
… To this end, while current approaches use only chemical rockets, it is important to study how a hybrid architecture affects performance. Hybrid systems are defined as an electric-chemical propulsion system or a chemical-nuclear thermal propulsion system. While there are many other variations, …
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A technical evaluation of a novel cell-surface cytokine detection technology
… become a tempting alternative to traditional chemical propulsion systems due to the great mass savings they provide through high specific impulses. However, a major stumbling block to their widespread integration is uncertainty about the thruster plume's interaction with spacecraft components. …
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Computational modeling of a Hall thruster plasma plume in a vacuum tank
… become a tempting alternative to traditional chemical propulsion systems due to the great mass savings they provide through high specific impulses. However, a major stumbling block to their widespread integration is uncertainty about the thruster plume's interaction with spacecraft components. …
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Propulsive and logistical feasibility of alternative future human-robotic Mars exploration architectures
… several variants including the use of Advanced Chemical Propulsion instead of Nuclear Thermal Rockets and the decomposition of the original mission into several that could, in the spirit of the Flexible Path, form the final steps on the way to a human landing on Mars. Comparison of selected …
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Modeling of Hall thruster lifetime and erosion mechanisms
Hall thrusters and other types of electric propulsion have become a tempting alternative to traditional chemical propulsion systems for in-space applications due to the high specific impulses (Isp) they provide. Large Isp translates to a highly desirable mass savings and system trades show that …
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Design of a Bimodal Chemical-Electrospray Propulsion System using Ionic Liquid Monopropellants
Two primary propulsion modes currently exist for spacecraft: chemical (e.g. monopropellant, cold gas, solid propellant) and electric (e.g. Hall thruster, ion engine, electrospray). Chemical propulsion typically offers high thrust and low specific impulse, while electric propulsion provides the …
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Uranus orbiter and probe mission : Project Upsilon
… and atmosphere. Three spacecraft - the Upsilon-0 Propulsion Module, the Upsilon-1 Science Orbiter, and the Upsilon-2 Atmosphere Probe - shall be implemented to meet needs, goals, and objectives as stated by the NASA Solar System Planetary Science Decadal Survey 2013-2022. Upsilon-0 shall be …
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Automated trajectory planning for multiple-flyby interplanetary missions
… trajectory. The first class of trajectories use chemical propulsion and may only apply a Δv at the periapse of each flyby. These Multiple Gravity Assist (MGA) trajectories are optimized using a cooperative algorithm of Differential Evolution (DE) and Particle Swarm Optimization (PSO). The second …
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Continuous-wave cavity ring down spectroscopy sensor for Hall thruster erosion measurement
Hall thruster and other Electric propulsion (EP) devices have become appealing alternatives to traditional chemical propulsion thrusters for space applications due to this high specific impulse (Isp), which allows high fuel efficiency. However, the uncertainty of the lifetime for Hall thruster …
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Gravity-assist trajectories to Venus, Mars, and the ice giants: Mission design with human and robotic applications
… (with the allowance of impulsive maneuvers using chemical propulsion) for launch dates ranging from 2024 to 2038 for Uranus and 2020 to 2070 for Neptune. Solutions are found using a patched conic model with analytical ephemeris via the Satellite Tour Design Program (STOUR), originally developed at …
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Molten Regolith Electrolysis reactor modeling and optimization of in-situ resource utilization systems
… systems and enabling orbital refueling of chemical propulsion systems to reduce launch vehicle mass. Unfortunately, significant uncertainty as to the mass, power, and performance of such ISRU systems has prohibited a rigorous quantitative analysis. To this end, parametric sizing models of …
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Solid-State Flow Control for Ion Electrospray Propulsion
Electrospray propulsion offers high-efficiency, low-mass propulsive capabilities, based on ion extraction from ionic liquid propellants, to small spacecraft that exceed the capabilities of conventional chemical propulsion. Two shortcomings of such propulsion systems is their lack of lightweight …
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Novel Gel-Infused Additively Manufactured Hybrid Rocket Solid Fuels
In the aerospace propulsion sector safety is an important driver to costs, vehicle design and mission capabilities. Hybrid rockets are considered some of the safest forms of chemical propulsion. That factor alone makes hybrid rocket propulsion systems desirable options. Hybrid systems often benefit …
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Advances in Baffled and Railed Tube Ram Accelerator Operation and Modeling
The ram accelerator is a novel chemical propulsion device capable of accelerating projectiles up to orbital velocities. It utilizes a ramjet-like propulsive cycle, where a projectile travels through a stationary tube filled with a gaseous propellant, experiencing high levels of thrust throughout …
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Utilizing an ExB probe for obtaining ion velocity distribution function for an electric propulsion system
Electric propulsion (EP) has been a key technology for contemporary and future space missions owing to its superior specific impulse and propellant efficiency relative to chemical propulsion. As EP applications expand from commercial constellations to deep-space exploration, the transition toward …
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Hybrid Chemical-Electric Propulsion Systems for CubeSats
… navigation, or science, miniaturized propulsion systems have been actively developed and demonstrated in-flight to support these applications. Propulsion systems are primarily divided into two main categories. Chemical propulsion systems benefit from high thrust to perform impulsive …
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Electrospray Thrusters in Chemical-Electric Multimode Propulsion for Small Satellites
Propulsion for small spacecraft is typically one of two modes, chemical or electric. These modes offer complementary propulsive performance: chemical propulsion provides high thrust and low specific impulse, while electric propulsion provides the inverse. As such, having access to both modes on the …
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Deep-Space Exploration Enabled by CubeSats with Staged Electrospray Propulsion
… as companions to enhance large missions or using propulsion to reach science orbits near the destination of the primary mission (e.g. to Mars or around the Moon). More CubeSat companions are planned on future high-profile missions and the concept is likely to continue to gain popularity, but is …
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