Session
Technical Session IV: Policies, Practices, or Methods to Enhance Low-Cost Space Access
Abstract
The advance in complexity and sophistication of small satellite missions is increasingly requiring that these spacecraft have on-board propulsion systems. However, there is a different emphasis on these small systems as opposed to the traditional propulsion systems on larger spacecraft. The systems must be low cost, low volume and safe. Traditionally cold gas nitrogen systems have been used as they provide a simple solution, combining high reliability with low cost and heritage. However cold gas systems tend to be limited by fairly low specific impulses and poor storage densities. One method of enhancing their performance, hence extending the mission life, is by heating the propellant to achieve a higher exhaust velocity. When this is done electrically with resistance heaters it is known as a resistojet. One feature of small satellites is that they are often power limited. Hence a balance must be struck between the propulsion system power requirements and the rest of the spacecraft. This paper will describe some of the features and limitations of using resistojets on small spacecraft and the evolution of the Surrey family of thrusters.
Presentation Slides
The Development of a Family of Resistojet Thruster Propulsion Systems for Small Spacecraft
The advance in complexity and sophistication of small satellite missions is increasingly requiring that these spacecraft have on-board propulsion systems. However, there is a different emphasis on these small systems as opposed to the traditional propulsion systems on larger spacecraft. The systems must be low cost, low volume and safe. Traditionally cold gas nitrogen systems have been used as they provide a simple solution, combining high reliability with low cost and heritage. However cold gas systems tend to be limited by fairly low specific impulses and poor storage densities. One method of enhancing their performance, hence extending the mission life, is by heating the propellant to achieve a higher exhaust velocity. When this is done electrically with resistance heaters it is known as a resistojet. One feature of small satellites is that they are often power limited. Hence a balance must be struck between the propulsion system power requirements and the rest of the spacecraft. This paper will describe some of the features and limitations of using resistojets on small spacecraft and the evolution of the Surrey family of thrusters.
