Liquid oscillator having control passages continuously communicating with ambient air

Claim 2

A fluidic oscillator for supplying aerated liquid pulses at a location below the surface of a body of liquid, said oscillator comprising: an interaction region; a power nozzle adapted to issue a power stream of liquid into the upstream end of said interaction region; said interaction region having first and second sidewalls, each positioned to effect boundary layer attachment of said power stream, such that said power stream has first and second stable positions in which it is attached to said first and second sidewalls, respectively; first and second outlet passages at the downstream end of said interaction region, each outlet passage positioned to receive said power stream in a different stable position; first and second control ports communicating with the upstream end of said interaction region through opposite sidewalls, said control ports being sufficiently proximate said issued power stream to be aspirated thereby and to deflect said power stream when the pressure differential between said control ports exceeds a predetermined pressure; oscillation control means responsive to power stream flow through either outlet passage for deflecting said power stream in said interaction region and thereby directing said power stream to the other outlet passage, said oscillation control means comprising: sensing means for sensing which outlet passage is receiving said power stream; flow control means responsive to sensing which outlet passage is receiving said power stream for flowing air at a relatively high flow rate to one control port and flowing liquid at a relatively low flow rate to the other control port to thereby provide a sufficiently higher pressure at said one control port than at said other control port to deflect said power stream to said other outlet passage.

Claim 3

The oscillator according to claim 1 wherein said first control port, said first interaction region sidewall, and said first outlet passage are disposed on one side of said oscillator, wherein said second control port, said second interaction region sidewall, and said second outlet passage are disposed on the opposite side of said oscillator; and wherein said first sidewall is oriented to direct said power stream when attached thereto to said first outlet passage, and said second sidewall is oriented to direct said power stream when attached thereto to said second outlet passage; wherein said sensing means comprises a first scoop passage positioned to receive a portion of the power stream flowing in said first outlet passage, and a second scoop passage positioned to receive a portion of the power stream flowing in said second outlet passage; and wherein said flow control means comprises: first and second feedback passages; first and second air passages; said first feedback passage being arranged to deliver liquid received by said first scoop passage to said second control port; said second feedback passage being arranged to deliver liquid received by said second scoop passage to said first control port; said first air passage being arranged to supply ambient air to said first feedback passage; and said second air passage being arranged to supply ambient air to said second feedback pressure.

Claim 4

The oscillator according to claim 1 wherein said interaction region is configured as a flow reversing chamber, wherein said first control port, said first interaction region sidewall, and said first outlet passage are disposed on one side of said oscillator; wherein said second control port, said second interaction region sidewall, and said second outlet passage are disposed on the opposite side of said oscillator; and wherein said first sidewall is oriented to direct said power stream when attached thereto to said second outlet passage, and said second sidewall is oriented to direct said power stream when attached thereto to said first outlet passage; wherein said sensing means comprises a first scoop passage positioned to receive a portion of the power stream flowing in said first outlet passage, and a second scoop passage positioned to receive a portion of the power stream flowing in said second outlet passage; and wherein said flow control means comprises: first and second feedback passages; first and second air passages; said first feedback passage being arranged to deliver liquid received by said first scoop passage to said first control port; said second feedback passage being arranged to deliver liquid received by said second scoop passage to said second control port; said first air passage being arranged to supply ambient air to said first feedback passage in the absence of power stream liquid in said first feedback passage; said second air passage being arranged to supply ambient air to said second feedback passage in the absence of power stream liquid in said second feedback passage.

Claim 5

The oscillator according to claim 1 wherein said first control port, said first interaction region sidewall, and said first outlet passage are disposed on one side of said oscillator; wherein said second control port, said second interaction region sidewall, and said second outlet passage are disposed on the opposite side of said oscillator; and wherein said first sidewall is oriented to direct said power stream when attached thereto to said first outlet passage, and said second sidewall is oriented to direct said power stream when attached thereto to said second outlet passage; wherein said sensing means comprises a first suction passage positioned to be aspirated by power stream flow through said first outlet passage, and a second suction passage positioned to be aspirated by power stream flow through said second outlet passage; and wherein said flow control means comprises: first and second open-ended standpipes arranged to extend vertically to above the surface of said body of liquid and connected at their lower ends to said first and second suction passages, respectively, such that the liquid level in said first standpipe rises to the surface of said body of liquid in the absence of power stream flow through said first outlet passage and is aspirated to some lower level by power stream flow through said first outlet passage, and such that the liquid level in said second standpipe rises to the surface of said body of liquid in the absence of power stream flow through said second outlet passage and is aspirated to some lower level by power stream flow through said second outlet passage; a first control passage connected from said first control port to a connection at said first standpipe between said surface level and lower level to permit air flow to said first control port when the liquid in said first standpipe is below said connection and to permit only water flow to said first control port when the liquid level in said first standpipe is above said connection; and a second control passage connected from said second control port to a connection at said second standpipe between said surface level and lower level to permit air flow to said first control port when the liquid in said second standpipe is below said connection and to permit only water flow to said first control port when the liquid in said second standpipe is above said connection.

Claim 6

The oscillator according to claim 1 wherein said interaction region is configured as a flow reversing chamber, wherein said first control port, said first interaction region sidewall, and said first outlet passage are disposed on one side of said oscillator; wherein said second control port, said second interaction region sidewall, and said second outlet passage are disposed on the opposite side of said oscillator; and wherein said first sidewall is oriented to direct said power stream when attached thereto to said second outlet passage, and said second sidewall is oriented to direct said power stream when attached thereto to said first outlet passage; wherein said sensing means comprises a first suction passage positioned to be aspirated by power stream flow through said first outlet passage, and a second suction passage positioned to be aspirated by power stream flow through said second outlet passage; and wherein said flow control means comprises: first and second open-ended standpipes arranged to extend vertically to above the surface of said body of liquid and connected at their lower ends to said first and second suction passages, respectively, such that the liquid level in said first standpipe rises to the surface of said body of liquid in the absence of power stream flow through said first outlet passage and is aspirated to some lower level power stream flow through said first outlet passage, and such that the liquid level in said second standpipe rises to the surface of said body of liquid in the absence of power stream flow through said second outlet passage and is aspirated to some lower level by power stream flow through said second outlet passage; a first control passage connected from said second control port to a connection at said first standpipe between said surface level and lower level to permit air flow to said second control port when the liquid in said first standpipe is below said connection and to permit only water flow to said second control port when the liquid level in said first standpipe is above said connections; and a second control passage connected from said first control port to a connection at said second standpipe between said surface level and lower level to permit air flow to said second control port when the liquid in said second standpipe is below said connection and to permit only water flow to said second control port when the liquid in said second standpipe is above said connection.

Claim 7

A fluidic oscillator of the type wherein a power stream of liquid is adapted to be issued alternately from first and second outlet passages at a submerged location in a liquid body in accordance with an oscillatory differential pressure applied between two control ports, said oscillator being characterized by means for continuously entraining ambient air in said power stream, said means comprising: means responsive to power stream flow through said first outlet passage for flowing air through one of said control ports, and to the absence of power stream flow through said first outlet passage for blocking air flow to said one control port; and means responsive to power stream flow through said second outlet passage for flowing air through the other of said control ports, and to the absence of power stream flow through said second outlet passage for blocking air flow to said other control port.

Claim 8

A fluidic oscillator of the type wherein a power stream of liquid is adapted to be issued alternately from first and second outlet passages at a submerged location in a liquid body in accordance with an oscillatory differential pressure applied between two control ports, said oscillator being characterized by means for continuously entraining ambient air in said power stream, said means comprising: means responsive to power stream flow through said first outlet passage for flowing air through one of said control ports, and to the absence of power stream flow through said first outlet passage for blocking air flow to said one control port; and means responsive to power stream flow through said second outlet passage for flowing air through the other of said control ports, and to the absence of power stream flow through said second outlet passage for blocking air flow to said other control port.

Claim 9

A fluidic oscillator of the type in which a liquid power stream is swept back and forth in a direction transversely of the stream flow direction, said oscillator comprising: an interaction region having an upstream and a downstream end; a power nozzle adapted to issue said power stream of liquid into the upstream end of said interaction region; said interaction region having first and second sidewalls, each positioned to define respective extreme transverse positions of said power stream as it is swept back and forth; outlet means located at the downstream end of said interaction region to receive said power stream and issue it from said interaction region in at least first and second outflow directions corresponding to said two extreme positions, respectively; first and second control passages communicating at one end with the upstream end of said interaction region through said first and second sidewalls, respectively, said control passages each additionally continuously communicating with ambient air; and oscillation control means responsive to power stream flow in either of said two outflow directions for deflecting said power stream in said interaction region and thereby directing said power stream to flow in the other of said two outflow directions.

Claim 10

A fluidic oscillator of the type in which a liquid power stream is swept back and forth in a direction transversely of the stream flow direction, said oscillator comprising: an interaction region having an upstream and a downstream end; a power nozzle adapted to issue said power stream of liquid into the upstream end of said interaction region; said interaction region having first and second sidewalls, each positioned to define respective extreme transverse positions of said power stream as it is swept back and forth; outlet means located at the downstream end of said interaction region to receive said power stream and issue it from said interaction region in at least first and second outflow directions corresponding to said two extreme positions, respectively; first and second control passages communicating at one end with the upstream end of said interaction region through said first and second sidewalls, respectively, said control passages each additionally continuously communicating with ambient air; and oscillation control means responsive to power stream flow in either of said two outflow directions for deflecting said power stream in said interaction region and thereby directing said power stream to flow in the other of said two outflow directions.

Claim 11

The oscillator according to claim 7 wherein said first control passage, said first interaction region sidewall, and said first outflow direction are disposed on one side of said oscillator; wherein said second control passage, said second interaction region sidewall, and said second outflow direction are disposed on the opposite side of said oscillator; and wherein said first sidewall is oriented to guide said power stream when flowing therealong in said first outflow direction, and said second sidewall is oriented to direct said power stream when flowing therealong in said second outflow direction.

Claim 12

The oscillator according to claim 7 wherein said interaction region is configured as a flow reversing chamber, wherein said first control passage, said first interaction region sidewall, and said first outflow direction are located on one side of said oscillator; wherein said second control passage, said second interaction region sidewall, and said second outflow direction are located on the opposite side of said oscillator; and wherein said first sidewall is oriented to direct said power stream when flowing therealong in said second outflow direction, and said second sidewall is oriented to direct said power stream when flowing therealong in said first outlet direction.