Abstract: An air handling unit for supplying air to a building including an exterior housing forming a chamber and having a longitudinal axis and air inlets and an outlet at opposite ends of the housing. An array of plenum fan units is mounted in the housing between its opposite end sections, this array extending transversely relative to the longitudinal axis. A corresponding array of insulated inlet flow concentrators is arranged adjacent to upstream ends of the plenum fan units. Each concentrator forms a flow passage which tapers towards an inlet opening of its respective fan unit. The flow passage is formed by a perforated metal wall circumferentially encased in sound attenuating material. Interior walls are mounted in the housing to separate the fan units from one another. At least one mechanism is mounted at one end of the compartment for each fan unit formed by the interior walls.

Abstract: A sound attenuating duct unit suitable for connection to an outlet of a gas turbine and an improved heat recovery apparatus for use with such a turbine are disclosed. The former unit includes a duct housing having exterior sides, an air inlet at one end and first and second air outlets. Interior walls define a main airflow passageway extending from the air inlet to both of the outlets. Sound absorbing and heat insulation material is arranged between these walls and the exterior sides. Sound attenuating members are mounted in the passageway and a diverter damper is mounted in the housing and is able to direct air flow to either one of the air outlets. The sound attenuating members are mounted between the diverter damper and the air inlet. The heat recovery apparatus includes a series of aerodynamic diffusers mounted in a housing adjacent an air flow inlet connectable to the gas turbine.

Abstract: A sound attenuating duct unit suitable for connection to an outlet of a gas turbine and an improved heat recovery apparatus for use with such a turbine are disclosed. The former unit includes a duct housing having exterior sides, an air inlet at one end and first and second air outlets. Interior walls define a main airflow passageway extending from the air inlet to both of the outlets. Sound absorbing and heat insulation material is arranged between these walls and the exterior sides. Sound attenuating members are mounted in the passageway and a diverter damper is mounted in the housing and is able to direct air flow to either one of the air outlets. The sound attenuating members are mounted between the diverter damper and the air inlet. The heat recovery apparatus includes a series of aerodynamic diffusers mounted in a housing adjacent an air flow inlet connectable to the gas turbine.

Abstract: A sound attenuating apparatus for mounting on a heat exchanging apparatus such as a cooling tower, this apparatus having an attenuator housing with vertically extending sides, a top cover and a bottom adapted for mounting on the tower. There is an annular air inlet in the bottom and an air outlet is formed in at least one of the sidewalls. Perforated interior walls are mounted in the housing and define an /airflow passageway that extends from the air inlet to the air outlet. These walls include a first annular wall section extending about and defining an outer circumferential portion of the airflow passageway and a second wall section with that is annular and extends about a substantially vertical central axis. The latter wall section defines an inner circumferential portion of the passageway. The second wall section extends generally upwardly and outwardly from the air inlet. Sound absorbing material is arranged behind the perforated walls.

Abstract: A sound attenuating duct unit suitable for connection to an outlet of a gas turbine and an improved heat recovery apparatus for use with such a turbine are disclosed. The former unit includes a duct housing having exterior sides, an air inlet at one end and first and second air outlets. Interior walls define a main airflow passageway extending from the air inlet to both of the outlets. Sound absorbing and heat insulation material is arranged between these walls and the exterior sides. Sound attenuating members are mounted in the passageway and a diverter damper is mounted in the housing and is able to direct air flow to either one of the air outlets. The sound attenuating members are mounted between the diverter damper and the air inlet. The heat recovery apparatus includes a series of aerodynamic diffusers mounted in a housing adjacent an air flow inlet connectable to the gas turbine.

Abstract: Both air duct inlet silencers and air duct outlet silencers for use with a stationary gas turbine are disclosed. The sound attenuating duct unit suitable for connecting to an outlet of a stationary gas turbine includes a housing having a horizontal housing section and a vertical housing section and having sidewalls surrounding a main airflow passageway that extends along a substantial bend. An air inlet is located at one end of the horizontal housing section and is adapted for connection to the outlet of the gas turbine. Preferably two air outlets are located proximate to an upper end of the vertical housing section. Splitters are mounted in the housing, and they divide sections of the main airflow passageway into smaller air passageways. At least one of the splitters is positioned upstream in the main airflow passageway relative to other splitters. The splitters contain sound attenuating material capable of withstanding airflow temperatures in the main airflow passageway of at least 500 degrees Celsius.

Abstract: A sound attenuating apparatus for mounting on a heat exchanging apparatus such as a cooling tower, this apparatus having an attenuator housing with vertically extending sides, a top cover and a bottom adapted for mounting on the tower. There is an annular air inlet in the bottom and an air outlet is formed in at least one of the sidewalls. Perforated interior walls are mounted in the housing and define an /airflow passageway that extends from the air inlet to the air outlet. These walls include a first annular wall section extending about and defining an outer circumferential portion of the airflow passageway and a second wall section with that is annular and extends about a substantially vertical central axis. The latter wall section defines an inner circumferential portion of the passageway. The second wall section extends generally upwardly and outwardly from the air inlet. Sound absorbing material is arranged behind the perforated walls.

Abstract: A sound attenuating apparatus for mounting on a heat exchanging apparatus such as a cooling tower, this apparatus having an attenuator housing with vertically extending sides, a top cover and a bottom adapted for mounting on the tower. There is an annular air inlet in the bottom and an air outlet is formed in at least one of the sidewalls. Perforated interior walls are mounted in the housing and define an /airflow passageway that extends from the air inlet to the air outlet. These walls include a first annular wall section extending about and defining an outer circumferential portion of the airflow passageway and a second wall section with that is annular and extends about a substantially vertical central axis. The latter wall section defines an inner circumferential portion of the passageway. The second wall section extends generally upwardly and outwardly from the air inlet. Sound absorbing material is arranged behind the perforated walls.

Abstract: A sound attenuating duct unit suitable for connection to an outlet of a gas turbine and an improved heat recovery apparatus for use with such a turbine are disclosed. The former unit includes a duct housing having exterior sides, an air inlet at one end and first and second air outlets. Interior walls define a main airflow passageway extending from the air inlet to both of the outlets. Sound absorbing and heat insulation material is arranged between these walls and the exterior sides. Sound attenuating members are mounted in the passageway and a diverter damper is mounted in the housing and is able to direct air flow to either one of the air outlets. The sound attenuating members are mounted between the diverter damper and the air inlet. The heat recovery apparatus includes a series of aerodynamic diffusers mounted in a housing adjacent an air flow inlet connectable to the gas turbine.

Abstract: Both air duct inlet silencers and air duct outlet silencers for use with a stationary gas turbine are disclosed. The sound attenuating duct unit suitable for connecting to an outlet of a stationary gas turbine includes a housing having a horizontal housing section and a vertical housing section and having sidewalls surrounding a main airflow passageway that extends along a substantial bend. An air inlet is located at one end of the horizontal housing section and is adapted for connection to the outlet of the gas turbine. Preferably two air outlets are located proximate to an upper end of the vertical housing section. Splitters are mounted in the housing, and they divide sections of the main airflow passageway into smaller air passageways. At least one of the splitters is positioned upstream in the main airflow passageway relative to other splitters. The splitters contain sound attenuating material capable of withstanding airflow temperatures in the main airflow passageway of at least 500 degrees Celsius.

Abstract: An air mixer for an air distribution system for a building including a set of fixed, parallel partitions arranged in a spaced-apart manner with one above another, these partitions forming alternating primary and secondary air passageways that are capable of conveying first and second air flows respectively. These passageways are substantially open ended at both inlet and outlet ends thereof. The primary air passageways extend from a first side of the mixer to a third, outlet side while the secondary air passageways extend at a substantial angle to the primary passageways from a second side to the third outlet side. There are fixed mixing devices, preferably in the form of curved vanes, arranged at many of the outlet ends of the passageways. The preferred air mixer has a substantially triangular shape in plan view.

Abstract: An air mixer for an air distribution system for a building including a set of fixed, parallel partitions arranged in a spaced-apart manner with one above another, these partitions forming alternating primary and secondary air passageways that are capable of conveying first and second air flows respectively. These passageways are substantially open ended at both inlet and outlet ends thereof. The primary air passageways extend from a first side of the mixer to a third, outlet side while the secondary air passageways extend at a substantial angle to the primary passageways from a second side to the third outlet side. There are fixed mixing devices, preferably in the form of curved vanes, arranged at many of the outlet ends of the passageways. The preferred air mixer has a substantially triangular shape in plan view.

Abstract: An air handling system for an enclosed space in a building includes two induction units that can be mounted above a ceiling. Each unit has an elongate air plenum section and an air mixing section forming an air mixing chamber. Air nozzles extend into the air mixing chamber and are mounted on a side of the air plenum section. Each nozzle has an inlet end opening into an interior chamber of the plenum section. Each air mixing section has an air outlet formed at a lower end thereof and a side air inlet for permitting return air to flow into the mixing chamber. Each induction unit is mounted so that the air mixing section extends at a substantial acute angle to the ceiling with the air outlet positioned where the mixing section meets the ceiling. The return air is drawn by a venturi effect created by the nozzles into each mixing chamber.

Abstract: An air mixer for an air distribution system for a building includes a set of fixed, substantially parallel partitions arranged in a spaced-apart, side-by-side manner, these partitions forming alternating primary and secondary air passageways. The primary air passageways are open-ended and extend from a front side to a rear side of the mixer. Front end plates extend respectively across front sides of the secondary air passageways and each has elongate edge portions extending along two opposite longitudinal edges thereof. Each elongate edge portion projects beyond the plane defined by an adjacent one of the partitions. Air flow splitters are mounted in the secondary air passageways and each is connected to an adjacent pair of the partitions. These splitters in operation of the mixer turn incoming air flow that enters the secondary air passageways towards the front end plates.

Abstract: A centrifugal fan apparatus for installation in an air plenum adapted to provide pressurized air to a ventilating system includes a centrifugal fan rotor having front and rear sidewalls and a number of blades extending between these sidewalls. The platform has a horizontal base frame on which wheels are rotatably mounted. The front sidewall has a central opening for receiving air while the rear sidewall is attached to a rotatable drive shaft that extends rearwardly from the rotor. A motor is connected to the shaft in order to rotate it and the rotor. A linearly movable platform supports the rotor, shaft and motor and an actuator moves this platform forwardly or rearwardly in order to control the volume of air flowing out of the rotor. An air inlet member is mounted rigidly at the central opening and has a generally cylindrical section that can extend into the rotor when the rotor is moved to a forward position.

Abstract: Combined air duct apparatus and silencer for attachment to both the inlet and the outlet of a fan unit for a building wherein each silencing apparatus has an exterior housing with an air inlet and an air outlet, one of which is adapted for connection to the fan unit. The inlet and outlet are connected by an airflow passageway defined by interior walls of the housing. First and second series of splitters are also provided in the outlet duct unit. The splitters in each series are spaced apart to form smaller air passageways and mounted side-by-side in a row. In the outlet duct unit, the air inlet is circular or annular while the outlet is rectangular. In one embodiment, the outlet lies in a plane at a substantial angle to the plane of the annular inlet and the main airflow passageway is substantially curved in its lengthwise direction.

Abstract: Combined air duct apparatus and silencer for attachment to both the inlet and the outlet of a fan unit for a building wherein each silencing apparatus has an exterior housing with an air inlet and an air outlet, one of which is adapted for connection to the fan unit. The inlet and outlet are connected by an airflow passageway defined by interior walls of the housing. A resonator chamber for reducing noise created by the fan unit extends around or is adjacent to the inlet or the outlet that is connected to the fan unit. The chamber is enclosed by chamber walls including a peripheral wall perforated with a number of holes and facing the airflow passageway. First and second series of splitters are also provided with those in each series being spaced apart to form smaller air passageways and mounted side-by-side in a row. The second series is positioned downstream of the first series. In the outlet duct unit, the air inlet is preferably circular while the outlet is rectangular.

Abstract: Combined air duct apparatus and silencer for attachment to both the inlet and the outlet of a fan unit for a building wherein each silencing apparatus has an exterior housing with an air inlet and an air outlet, one of which is adapted for connection to the fan unit. The inlet and outlet are connected by an airflow passageway defined by interior walls of the housing. A resonator chamber for reducing noise created by the fan unit extends around or is adjacent to the inlet or the outlet that is connected to the fan unit. The chamber is enclosed by chamber walls including a peripheral wall perforated with a number of holes and facing the airflow passageway. First and second series of splitters are also provided with those in each series being spaced apart to form smaller air passageways and mounted side-by-side in a row. The second series is positioned downstream of the first series. In the outlet duct unit, the air inlet is preferably circular while the outlet is rectangular.

Abstract: A non-fibrous acoustic silencing duct member capable of attenuating noise associated with a gaseous medium passing through it. Perforated sidewalls define a gas flow passageway and include at least two opposing walls, each perforated with a number of small holes distributed over its surface. Exterior sidewalls are positioned on the outside of the perforated sidewalls and are spaced therefrom. Enclosed chambers are formed between the perforated and exterior sidewalls, which chambers are of selected depths. One or more screen layers extend along and adjacent to outer surfaces of the perforated sidewalls, these screen layers being located in the chambers. Each screen layer is covered with an array of very small holes that are substantially smaller than the holes in the adjacent perforated sidewall. Internal dividers extend between each perforated sidewall and its respective exterior sidewall in order to divide the space between the sidewalls.

Abstract: Combined air duct apparatus and silencer for attachment to both the inlet and the outlet of a fan unit for a building wherein each silencing apparatus has an exterior housing with an air inlet and an air outlet, one of which is adapted for connection to the fan unit. The inlet and outlet are connected by an airflow passageway defined by interior walls of the housing. A resonator chamber for reducing noise created by the fan unit extends around or is adjacent to the inlet or the outlet that is connected to the fan unit. The chamber is enclosed by chamber walls including a peripheral wall perforated with a number of holes and facing the airflow passageway. First and second series of splitters are also provided with those in each series being spaced apart to form smaller air passageways and mounted side-by-side in a row. The second series is positioned downstream of the first series. In the outlet duct unit, the air inlet is preferably circular while the outlet is rectangular.