A gaseous compression system for compressing a gas from an initial pressure to an exit pressure with a first, blower compression bank and a second, mechanical compression bank. Each compression bank has plural stages of gaseous compression with a gaseous fluid compressor and a heat pump intercooler. The heat pump intercooler comprises a cascading heat pump intercooler with a high temperature section, a medium temperature section, and a low temperature section, each temperature section with an intercooler core. Each stage of the blower compression bank has a high-pressure blower, and each stage of the mechanical compressor bank has a mechanical compressor. A final stage of gaseous compression is without a heat pump intercooler. Gas compressed by the gaseous fluid compression system can be injected into a gas-driven generator to generate electric power from movement of a working fluid induced by injection of the compressed gas.

A process for producing compressed hydrogen gas including: electrolysing water to produce hydrogen gas, and compressing the hydrogen gas in a multistage compression system including: a centrifugal compression stage and a recycle system for recycling a portion of the hydrogen gas from a product end to a feed end of the centrifugal compression stage; wherein hydrogen gas feed is fed to the feed end at a pre-determined feed temperature and pressure and mole fraction of water; wherein a portion of the hydrogen gas is removed from the product end, reduced in pressure in the recycle system to the pre-determined feed pressure and is then recycled to form at least part of the hydrogen gas feed to the centrifugal compression stage; and further including cooling hydrogen gas comprising the reduced pressure hydrogen gas such that the water mole fraction in the hydrogen gas feed is at the pre-determined water mole fraction.

A process for producing compressed hydrogen gas including: electrolysing water to produce hydrogen gas, and compressing the hydrogen gas in a multistage compression system including: a centrifugal compression stage and a recycle system for recycling a portion of the hydrogen gas from a product end to a feed end of the centrifugal compression stage; wherein hydrogen gas feed is fed to the feed end at a pre-determined feed temperature and pressure and mole fraction of water; wherein a portion of the hydrogen gas is removed from the product end, reduced in pressure in the recycle system to the pre-determined feed pressure and is then recycled to form at least part of the hydrogen gas feed to the centrifugal compression stage; and further including cooling hydrogen gas comprising the reduced pressure hydrogen gas such that the water mole fraction in the hydrogen gas feed is at the pre-determined water mole fraction.

A refrigeration system, in particular a transport refrigeration system, comprising: a refrigerant circuit, which in particular works using CO.sub.2 as the refrigerant and in which there is guided a total mass flow of the refrigerant; a high-pressure-side heat exchanger arranged in the refrigerant circuit and cooling refrigerant compressed to a high pressure; at least one cooling stage which expands the principal mass flow from the intermediate-pressure collector to a low pressure in at least one cooling expansion member and in so doing makes refrigeration capacity available at a low-pressure-side heat exchanger; and a refrigerant compressor unit which compresses the principal mass flow from a low pressure to a high pressure, wherein the refrigerant compressor unit has a first compressor stage for compressing, to a medium pressure, the refrigerant of the principal mass flow supplied at low pressure, and a second compressor stage for compressing, to a high pressure, the refrigerant of the principal mass flow that has been compressed to a medium pressure.

A variable-pressure air pump includes a first cylinder with a first chamber and a second cylinder with a second chamber movably connected with one another. The second chamber fluidly communicable with the outside of the variable-pressure air pump selectively. A discharge device includes a connecting member and a switch movably connected with one another. The connecting member defines at least one discharge hole fluidly connecting with the second chamber. The switch has at least one flow guide portion and at least one blocking portion. The switch is movable between a first position in which the at least one flow guide portion is adjacent and opens to the at least one discharge hole and a second position in which the at least one blocking portion is adjacent to and blocks the at least one discharge hole.

Disclosed are a variable capacity compressor operation mode determination method and device, a variable capacity compressor and an air conditioner. The variable capacity compressor operation mode determination method includes: detecting a current value of a compressor at present as A1 before switching an operation mode of the compressor; detecting the current value of the compressor at present as A2 after switching the operation mode of the compressor and reaching a preset time; comparing A1 and A2, determining that the switching of the operation mode of the compressor is successful when a ratio relationship between A1 and A2 satisfies a preset condition, and determining that switching of the operation mode of the compressor is failed when the ratio relationship between A1 and A2 dissatisfies a preset condition.

A device and method are used for changing the compression ratio of a reciprocating compressor. The device includes compression chambers pneumatically connected between an inlet and an outlet port. Communication valves change the number of compression steps and are arranged to switch from a first to a second open/closed state combination, or vice-versa. A lower number and a higher number, and vice-versa, respectively, of the compression chambers include chambers serially connected to one another, so that a gas is subjected to a number of compression steps that increases when switching from the first to the second combination and decreases when switching in the opposite direction. A control unit receives pressure signals upstream and downstream of the reciprocating compressor, respectively, to compute the corresponding pressure ratios, to generate opening/closing control signals responsive to the pressure ratios, and to transfer the control signals to actuators of the commutation valves.

The invention relates to a method for operating a piston compressor (100) having a reciprocating piston (111) in a cylinder (110), wherein an inlet valve (112) and an outlet valve (113) are provided in the cylinder (110) on the side of a medium (b) which is to be compressed and conveyed, wherein the reciprocating piston (111) is moved to and fro by way of a hydraulic drive (120, 121) with a hydraulic piston (120) with the use of a hydraulic medium (a) in a first volume (141), with which the reciprocating piston (111) is loaded on the side of the hydraulic drive (120, 121), wherein, if required, hydraulic medium (a) is fed into the first volume (141) and/or is discharged from the first volume (141) in a manner which is dependent on a position of the hydraulic piston (120) and/or a rotational angle ((p) of a shaft (121) which is provided for moving the hydraulic piston (120) in relation to a position (x) of the reciprocating piston (120) and/or a pressure (p) in the first volume (141), and to a piston compressor (100) of this type.

A fluid control device includes a piezoelectric pump, a piezoelectric pump, a valve, and a container. The piezoelectric pump and the piezoelectric pump repeat the operation and the stop in accordance with a drive control cycle. The valve starts a control to close at the start timing of one cycle of the drive control cycle and starts a control to open at the stop of the piezoelectric pump and the piezoelectric pump. The time from the start timing of one cycle of the drive control cycle to the time at which the piezoelectric pump on the upstream side pump reaches a normal operation drive voltage is longer than the time from the start timing to the time at which the piezoelectric pump on the downstream side reaches a normal operation drive voltage.

A fluid control device includes a piezoelectric pump, a piezoelectric pump, a valve, and a container. The piezoelectric pump and the piezoelectric pump repeat the operation and the stop in accordance with a drive control cycle. The valve starts a control to close at the start timing of one cycle of the drive control cycle and starts a control to open at the stop of the piezoelectric pump and the piezoelectric pump. The time from the start timing of one cycle of the drive control cycle to the time at which the piezoelectric pump on the upstream side pump reaches a normal operation drive voltage is longer than the time from the start timing to the time at which the piezoelectric pump on the downstream side reaches a normal operation drive voltage.