development of a solar thermal propulsion system
- Paper number
IAC-08.C4.6.5
- Author
Mr. Harrie Leenders, Delft University of Techonology (TU Delft), The Netherlands
- Coauthor
Mr. Barry Zandbergen, Delft University of Technology, The Netherlands
- Year
2008
- Abstract
At the Delft University of Technology the use of solar radiation to heat a propellant to a high temperature is investigated as an alternative to resistance heating. The main advantage of solar heating is that the energy of the Sun is directly used to heat the propellant, whereas for resistance heating this energy must first be converted to electrical energy and than to heat. The latter only allows for an efficiency of about 25
Theoretical work includes the development of a model that allows for the design and prediction of a solar thermal thruster. The design goal is to reach an as high as possible propellant temperature and efficient energy usage. The model includes calculations on energy transfer from the light source to the receiver-absorber-converter (RAC) and from the RAC to the propellant due to forced convection. Furthermore thruster performance is taken into account as are heat losses due to radiation and free convection. Based on the simulation results CAD drawings of the design have been made.
From the CAD drawings a laboratory thruster has been built. It essentially consists of the RAC unit plus nozzle. Main features of the RAC are that it is conically shaped and consists of two main components, the inner and outer cone. Both parts have a cavity in them and are manufactured out of copper. On the inner cone 8 equally spaced propellant channels are milled which are closed off by the outer cone, when the inner cone is placed in the cavity of the outer cone. The cavity wall of the inner cone functions as the receiver and absorber of the RAC where the incoming light is absorbed.
The system is tested at different mass flow ranges to determine the relation between input power, propellant temperature and jet power. These tests are being performed in a laboratory environment using the Delft Aerospace Rocket Test Stand. An artificial light source and a collecting and concentrating system have been added to direct the heat into the heat absorbing cavity. Gaseous nitrogen is used as propellant. Measurement parameters are generated thrust, propellant temperature and pressure. Finally conclusions and recommendations are presented.
- Abstract document
- Manuscript document
IAC-08.C4.6.5.pdf (🔒 authorized access only).
To get the manuscript, please contact IAF Secretariat.