Hydrogen peroxide decomposition in serpentine mini channel with silver catalyst

Abstract

Micro thrusters were used to produce thrust in the order of a few Newtons to position satellites and other designed space objects. For such applications, monopropellant thrusters using hydrogen peroxide are preferred for their high maneuverability, accurate positioning, and attitude control. Hydrogen peroxide is a green monopropellant that forms the products (water and vapor) after it gets decomposed in contact with a catalyst. Complete catalytic decomposition of hydrogen peroxide is still a challenging task. In the present work, 30% of hydrogen peroxide concentration with silver catalyst (modified geometry) were used to increase reaction rate. The effect of silver placed at different locations in serpentine and straight mini channels (same dimensions) is analyzed. The analysis is done for a varied number of silver catalysts placed at different locations in serpentine and straight mini channels having a diameter of 0.25 cm. The serpentine mini channel shows better decomposition of hydrogen peroxide especially at shorter length of 10 cm than the straight mini channel with the same length of catalyst because of its better mixing capability due to non-uniformity in the flow field, especially at the bend sections. The results will be useful in determining the appropriate geometry and placement of the catalyst for efficient monopropellant decomposition.