Abstract: A liquid oxidizer immersion hybrid rocket having a combustion chamber, a porous fuel material placed in the combustion chamber, a liquid oxidizer filled into pores of the porous fuel material, and two holding plates provided in the combustion chamber so as to hold opposite ends of the porous fuel material respectively. The porous fuel material comprises a large number of layers stacked one another in an axial direction of the combustion chamber.

Abstract: A heater for use with a Stirling engine and a method for heating a working fluid for a Stirling engine is disclosed. The heater has a burner, heater tubes disposed in the burner, a space formed around the heater tubes which is filled with heat-storing material, and a high-temperature heat source. The heat-storing material is sealed by a seal member. Heat produced by the high-temperature heat source is supplied to the heater tubes via the heat-storing material; hence the heat-storing material acts as a secondary heat source. Heat is stored in the heat-storing material in the form of sensible heat or latent heat, or a chemical reaction is employed.