Abstract: An exemplary walk-in refrigeration system comprises an insulated compartment. A supply plenum is disposed between a roof insulation wall and a ceiling panel. A pair of opposing wall plenums are respectively defined between a corresponding lateral insulation wall and a corresponding interface wall. Each wall plenum is in airflow communication between the supply plenum and a respective shelf refrigeration zone. A walk-in zone is disposed between the shelf refrigeration zones. The interface walls each include a plurality of flow discharge ports which direct airflow from the respective wall plenum to the respective shelf refrigeration zone. Each interface wall may comprise an array of removable and replaceable interface panels. The interface panels may each include a vent segment with one or more capture inlet ports. An actuatable metering element on the vent segment may allow a user to selectably restrict airflow through the capture inlet ports independently for each interface panel.

Abstract: An exemplary walk-in refrigeration system comprises an insulated compartment. A supply plenum is disposed between a roof insulation wall and a ceiling panel. A pair of opposing wall plenums are respectively defined between a corresponding lateral insulation wall and a corresponding interface wall. Each wall plenum is in airflow communication between the supply plenum and a respective shelf refrigeration zone. A walk-in zone is disposed between the shelf refrigeration zones. The interface walls each include a plurality of flow discharge ports which direct airflow from the respective wall plenum to the respective shelf refrigeration zone. Each interface wall may comprise an array of removable and replaceable interface panels. The interface panels may each include a vent segment with one or more capture inlet ports. An actuatable metering element on the vent segment may allow a user to selectably restrict airflow through the capture inlet ports independently for each interface panel.

Abstract: A pulsing apparatus for use in a conduit through which is flowing a liquid. The pulsing apparatus includes a housing in which is positioned a valve generally at the inlet of the housing, the valve controlling flow of fluid down a central passageway of the housing. There is also flow through an annulus of the housing formed in part by at least one rotor and one stator, the rotor rotating in response to fluid flow impinging on the vanes of the rotor. There is a second valve provided in the lower end of the housing through which flow can be intermittently interrupted to cause pressure pulses in the mud flow and hence in the conduit in which the pulsing apparatus is disposed, the second valve being operatively connected to the rotor.

Abstract: A downhole pulsing apparatus having a tubular housing, a first valve assembly positioned in the housing, first and second turbine stages each comprising a stator and a rotor positioned in the housing below the first valve assembly and a second valve assembly positioned in the housing. There is a tubular mandrel connected for rotation of the rotors of the turbine stages and to a second valve assembly. The first valve assembly includes a valve element which is movable between a first position wherein pressurized fluid flow entering the housing is directed to the first turbine assembly, and a second position wherein the fluid flow is directed primarily axially through the apparatus so as to partially bypass the first turbine stage.