A multistage aspirator for an inflatable assembly may comprise a first end defining a primary gas inlet and a second end defining a gas outlet. An internal surface of the multistage aspirator may define a flow path extending from the primary gas inlet to the gas outlet. A first stage of the multistage aspirator may include a first stage orifice extending from the internal surface to an external surface of the multistage aspirator. A second stage of the multistage aspirator may include a second stage orifice located downstream of the first stage orifice and extending from the external surface to the internal surface.

A convergent nozzle is in a flow path from a liquid inlet of the ejector and a liquid outlet of the ejector. A convergent end of the convergent nozzle has a smaller cross-sectional area than an inlet of the convergent nozzle. The convergent nozzle is sized to increase a velocity of the liquid to supersonic velocities and decrease a pressure of the liquid. A low pressure housing includes a low pressure inlet into an interior of the low pressure housing. A convergent-divergent nozzle includes a mixed liquid inlet in fluid communication to receive fluid from the convergent nozzle and the low pressure housing.

An ejector includes a first nozzle, a second nozzle, an atomization mechanism, and a mixer. A working fluid in a liquid phase is supplied to the first nozzle as a drive flow. A working fluid in a gas phase is sucked into the second nozzle. The atomization mechanism is disposed at an end of the first nozzle and atomizes the working fluid in a liquid phase while maintaining the liquid phase. The mixer generates a fluid mixture by mixing the atomized working fluid generated by the atomization mechanism and the working fluid in a gas phase sucked into the second nozzle. The atomization mechanism includes an ejection section that generates a jet of the working fluid in a liquid phase and a collision surface with which the jet from the ejection section collides. The collision surface is inclined with respect to a direction in which the jet flows.

A quick-release vacuum pump which is mainly applied to a vacuum transport system. The vacuum pump has a mechanism in which part of compressed air supplied for generating a vacuum state is stored firstly in a chamber, and then the vacuum state within the chamber is released when transportation is completed. When the vacuum state is released, a check valve is moved by the pressure of air that flows backward. The range of movement of the check valve is adjusted by a control means. An air filter is disposed at the lower end of the check valve. The release of the vacuum state is quick and controllable. Also, the filter is naturally filtered and cleaned.

A multistage vacuum includes a tank and a vacuum generating head mounted on the tank. The vacuum generating head includes a housing having multiple chambers and a gang of parallel multistage ejectors, where the respective stages of each ejector share a common chamber.

A pump comprises: a vertically-extending conduit having an intermediate portion extending between lower and upper portions, the intermediate portion having a cross-sectional area smaller than that of the upper portions, a lift arrangement including an array of ports arranged over a length of the lower portion, each port of the array having a terminus at the lower portion and extending horizontally away from the terminus such that the working fluid is directed towards a center of the conduit; and an injector having a terminus at the top of the intermediate portion and extending vertically downwardly such that the working fluid is directed vertically upwardly, the terminus of the injector being defined by a cylindrical groove, an annular chamber surrounding the injector, having a length and communicating with the injector through a row of apertures spaced a distance from the junction of the transition portion and the intermediate portion.

An example injector includes a first conduit defining a first flow path including a first choke for a first fluid and a second conduit defining a second flow path including a second choke for a second fluid. The second choke is defined by a converging region upstream and a diverging region downstream of the second choke. The example injector further includes a mixing region after both the diverging region of the second flow path and the first choke and configured to receive the first fluid the second fluid, and an outlet configured to allow the first fluid and the second fluid to exit the mixing region. The first and second chokes are configured to allow a constant mass flow of the first and second fluids, respectively, to flow into the mixing region independent of a pressure at the outlet.

A pump comprises: a vertically-extending conduit having an intermediate portion extending between lower and upper portions, the intermediate portion having a cross-sectional area smaller than that of the upper portions, a lift arrangement including an array of ports arranged over a length of the lower portion, each port of the array having a terminus at the lower portion and extending horizontally away from the terminus such that the working fluid is directed towards a center of the conduit; and an injector having a terminus at the top of the intermediate portion and extending vertically downwardly such that the working fluid is directed vertically upwardly, the terminus of the injector being defined by a cylindrical groove, an annular chamber surrounding the injector, having a length and communicating with the injector through a row of apertures spaced a distance from the junction of the transition portion and the intermediate portion.

A jet pump may include a body that may include an inlet portion having a motive port and a first induce port, a throat, a tapered wall connecting the inlet portion with the throat, a discharge port, and a diffuser connecting the throat and the discharge port. The tapered wall may include a converging angle of about 5 degrees.

A multistage aspirator for an inflatable assembly may comprise a first end defining a primary gas inlet and a second end defining a gas outlet. An internal surface of the multistage aspirator may define a flow path extending from the primary gas inlet to the gas outlet. A first stage of the multistage aspirator may include a first stage orifice extending from the internal surface to an external surface of the multistage aspirator. A second stage of the multistage aspirator may include a second stage orifice located downstream of the first stage orifice and extending from the external surface to the internal surface.