Abstract: A micromechanical pressure relief valve arrangement comprises a stack of wafers. An active pressure relief valve is realized within the stack of wafers. A passive pressure relief valve is also realized within the stack of wafers, arranged in parallel to the active pressure relief valve. A check valve, also realized within the stack of wafers, is arranged in series with both the active pressure relief valve and the passive pressure relief valve.

Abstract: A filter comprises a stack of wafers (28). Each of the wafers has a through hole (6). Edges (7) of the holes together define an internal tube. An interface (32) between adjacent wafers defines filter channels. The filter channels comprises first coarse filter channels (20), second coarse filter channels (22) and fine filter channels (26). The first coarse filter channels are open towards an outer rim (5), extend in a direction from the outer rim and are closed towards the internal tube. The second coarse filter channels are arranged in an opposite manner. The fine filter channels connect the first and second coarse filter channels. The first and second coarse filter channels extend radially (R) and the fine filter channels extend tangentially (T). The first and second coarse filter channels are defined by recesses in a surface of a first wafer and the fine filter channels are defined by recesses, each one encircling the hole, in a surface of a second wafer.

Abstract: A nozzle arrangement for use in a gas thruster is presented. At least one heater micro structure (20) is arranged in a stagnation chamber (12) of the gas thruster. The heater microstructure (20) comprises a core of silicon or a silicon compound coated by a surface metal or metal compound coating. The heater microstructure (20) is manufactured in silicon or a silicon compound and covered by a surface metal coating. The heater microstructure (20) is mounted in the stagnation chamber (12) before or after the coverage of the surface metal or metal compound coating. The coverage is performed by heating the heater microstructure and flowing a gas comprising low quantities of a metal compound. The compound decomposes at the heated heater microstructure (20), forming the surface metal or metal compound coating. The same principles of coating can be used for repairing the heater microstructure (20) in situ.

Abstract: A micromechanical pressure relief valve arrangement (10) comprises a stack of wafers (13). An active pressure relief valve (20) is realized within the stack of wafers (13). A passive pressure relief valve (30) is also realized within said stack of wafers (13), arranged in parallel to the active pressure relief valve (20). A check valve (50), also realized within the stack of wafers (13), is arranged in series with both the active pressure relief valve (20) and the passive pressure relief valve (30).

Abstract: A nozzle arrangement for use in a gas thruster is presented. At least one heater micro structure (20) is arranged in a stagnation chamber (12) of the gas thruster. The heater microstructure (20) comprises a core of silicon or a silicon compound coated by a surface metal or metal compound coating. The heater microstructure (20) is manufactured in silicon or a silicon compound and covered by a surface metal coating. The heater microstructure (20) is mounted in the stagnation chamber (12) before or after the coverage of the surface metal or metal compound coating. The coverage is performed by heating the heater microstructure and flowing a gas comprising low quantities of a metal compound. The compound decomposes at the heated heater microstructure (20), forming the surface metal or metal compound coating. The same principles of coating can be used for repairing the heater microstructure (20) in situ.

Abstract: The present invention relates to a reactor for the decomposition of ammonium dinitramide-based liquid monopropellants into hot, combustible gases for combustion in a combustion chamber, and more particularly a rocket engine or thruster comprising such reactor and a combustion chamber. The invention also relates to a process for the decompostion of ammonium dinitramide-based liquid monopropellants.

Abstract: The present invention relates to a reactor for the decomposition of ammonium dinitramide-based liquid monopropellants into hot, combustible gases for combustion in a combustion chamber, and more particularly a rocket engine or thruster comprising such reactor and a combustion chamber. The invention also relates to a process for the decompostion of ammonium dinitramide-based liquid monopropellants.