Abstract: A gas resonance device (101) comprises a pulsed combustor (102) located in the middle of a substantially spherical resonance chamber (103). Such a thermally driven gas resonance device has the advantage that the wall friction losses are eliminated altogether. A thermally driven gas resonance device (1, 101) may be combined with a pressure swing gas separator (16, 108), the oscillating gas in the gas resonance device (1, 101) being used to provide the pressure changes required to drive the pressure swing gas separator. Alternatively a thermally driven gas resonance device (1, 101) is combined with a heat pump (19, 120) with the oscillating gas in the gas resonance device (1, 101) being used to provide the power to operate the heat pump. The thermally driven gas resonance device (1, 101) may also drive an electrical generator (121, 122) to provide a combined heat and power device.

Abstract: A pressure swing gas separator is operated with a pressure difference between its pressurized and depressurized states of less than 0.1 bar. The separator operates at a repetition frequency greater than one cycle per second and preferably between 50 and 200 cycles per second. The separator includes a bed (16, 108, 147) which preferably forms part of a resonant system. A drive for resonant system may be taken from a thermally driven gas resonance device (1, 101) or may be provided by an electrical actuator (140). Preferably the bed is covered by a diaphragm (109, 133, 141) which, as it oscillates, pressurizes and depressurizes the bed of adsorbent material. The diaphragm may cooperate with an annular valve seat (114) to provide a valve to control the entry of gas into the bed.

Abstract: A thermally driven gas resonance device includes a resonance tube (3) which expands in cross-section along its length from one end to the other, a heat source (2) located at the one end of the resonance tube, and an igniter (14) to trigger oscillations in a gas in the tube. The heat source (2) is preferably a pulsed heat source having a repetition frequency corresponding to a resonant frequency of the gas tube (3). The mechanical energy produced in the oscillating gas may be used to operate a pressure swing gas separator by including a bed (16) of molecular sieve material in the other end of the tube (3). Alternatively, the mechanical energy may be used to drive a heat pump (19). In this case a heat sink (21) is located at the other end of the tube (3), a regenerator (20) is also located adjacent the other end, and ports (8) on the side of the regenerator (20) towards the heat source (2) effect heat exchange between the gas in the resonance tube (3) and a source of low grade heat.

Abstract: A thermally driven gas resonance device includes a resonance tube (3) which expands in cross-section along its length from one end to the other, a heat source (2) located at the one end of the resonance tube, and an igniter (14) to trigger oscillations in a gas in the tube. The heat source (2) is preferably a pulsed heat source having a repetition frequency corresponding to a resonant frequency of the gas tube (3). The mechanical energy produced in the oscillating gas may be used to operate a pressure swing gas separator by including a bed (16) of molecular sieve material in the other end of the tube (3). Alternatively, the mechanical energy may be used to drive a heat pump (19). In this case a heat sink (21) is located at the other end of the tube (3), a regenerator (20) is also located adjacent the other end, and ports (8) on the side of the regenerator (20) towards the heat source (2) effect heat exchange between the gas in the resonance tube (3) and a source of low grade heat.