Flueric Sun Sensor-Actuator, A Solar Attitude Control System 670553
A preliminary analytical investigation of a flueric solar attitude control device performing the functions of both sensor and actuator was conducted. The system cycle was based upon only incident solar energy as the power source and heat rejection by radiation to space. The working fluid continuously experiences a change of phase from liquid to vapor and recondensation to liquid. The fluid in the liquid phase is pumped by surface tension forces in a porous wick material within the annular volume and also provides large surface area for the heat exchange function in the evaporator.
As a result of angular misalignment from the sun direction an unbalanced mass flow develops. From consideration of the redistribtuion of angular momentum (in the sense of a momentum flywheel) it was shown that the vehicle can be rotated to reestablish alignment with the sun direction. The numerical results indicate the feasibility of the concept for space applications. Initial design estimates for space vehicle applications were shown in terms of the vehicle mass and required radiant energy exchange areas.