Solar thermal propulsion

A further special area of propulsion systems is Chemical Thermal Propulsion (CTP). CTP is defined in contrast to STP (solar thermal propulsion) and NTP (nuclear thermal propulsion). In CTP, in a very exothermic chemical reaction in a closed system, heat but no pressure is generated since the products of the reaction are solid or liquid. The heat energy is then transferred to a liquid medium (the propellant) using a heat exchanger, which is responsible for the propulsion of for example, the torpedo. Suitable propellants are e.g. water (the torpedo can suck it in directly from its surroundsings) or H2 or He, due to their very low molecular or atomic masses. The basic principles of CTP can also be used in special heat generators. A good example for a chemical reaction which is suitable for CTP is the reaction of (non-toxic) SF6 (sulfur hexafluoride) with easily liquified lithium (m.p. 180 °C) ... 

Winters, BA., 1996. Analysis of the solar thermal upper stage technology demonstrator liquid acquisition device with integrated thermodynamic vent system. In AIAA-96-2745 32nd Joint Propulsion Conference, Lake Buena Vista, FL, July 13. 

This paper represents one phase of research carried out at the Jet Propulsion Laboratory, California Institute of Technology, sponsored by the National Aeronautics and Space Administration, Contract NAS7-100. Work at JPL and University of California, Riverside was supported by the RAD task of the Solar Thermal Power Systems project sponsored by the Department of Energy. Work at... 

The nominal set consists of the elements necessary for nominal operation (propulsion, navigation, electrical power (solar panels, batteries), management of the exchange of measurements and commands with the ground and the international station, thermal control, equipment monitoring), coimected by a set of avionics buses to a group of computers. 

VF-6 has a diameter of 7.6m (24.9 ft) and length of 21m (68.9 ft), and is intended for power system testing and high power ion propulsion This facility can simulate Earth and Mercury solar power concentrations and space thermal conditions (using a liquid nitrogen cooled shroud). The system is able to reject 2400 kW of thermal energy As with VF-5, the facility allows for automated, unattended operation. 

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