The present disclosure relates to refrigeration. More particularly, it relates to ejector refrigeration systems.
Earlier proposals for ejector refrigeration systems are found in U.S. Pat. Nos. 1,836,318 and 3,277,660.
In the normal mode of operation, gaseous refrigerant is drawn by the compressor 22 through the suction line 56 and inlet 24 and compressed and discharged from the discharge port 26 into the discharge line 28. In the heat rejection heat exchanger, the refrigerant loses/rejects heat to a heat transfer fluid (e.g., fan-forced air or water or other fluid). Cooled refrigerant exits the heat rejection heat exchanger via the outlet 34 and enters the ejector primary inlet 40 via the line 36.
The exemplary ejector 38 (
Use of an ejector serves to recover pressure/work. Work recovered from the expansion process is used to compress the gaseous refrigerant prior to entering the compressor. Accordingly, the pressure ratio of the compressor (and thus the power consumption) may be reduced for a given desired evaporator pressure. The quality of refrigerant entering the evaporator may also be reduced. Thus, the refrigeration effect per unit mass flow may be increased (relative to the non-ejector system). The distribution of fluid entering the evaporator is improved (thereby improving evaporator performance). Because the evaporator does not directly feed the compressor, the evaporator is not required to produce superheated refrigerant outflow. The use of an ejector cycle may thus allow reduction or elimination of the superheated zone of the evaporator. This may allow the evaporator to operate in a two-phase state which provides a higher heat transfer performance (e.g., facilitating reduction in the evaporator size for a given capability).
The exemplary ejector may be a fixed geometry ejector or may be a controllable ejector.
One aspect of the disclosure involves an ejector having: a motive flow inlet; a secondary flow inlet; an outlet; a motive nozzle; a diffuser; and a control needle shiftable between a first position and a second position. The ejector comprises: an inlet body bearing the motive flow inlet and the secondary flow inlet; a diffuser body forming the diffuser and bearing the outlet; a motive nozzle insert forming the motive nozzle in a compartment in the inlet body; and a needle guide insert in the motive nozzle insert.
In one or more embodiments of any of the foregoing embodiments, the needle guide insert is brazed to the motive nozzle insert.
In one or more embodiments of any of the foregoing embodiments, the motive nozzle insert is brazed to the compartment.
In one or more embodiments of any of the foregoing embodiments, the inlet body is a first piece and the diffuser body is a second piece.
In one or more embodiments of any of the foregoing embodiments, the inlet body is metallic and the diffuser body is metallic.
In one or more embodiments of any of the foregoing embodiments, the inlet body is threaded to the diffuser body.
Another aspect of the disclosure involves an ejector having: a motive flow inlet; a secondary flow inlet; an outlet; a motive nozzle; and a diffuser. The ejector comprises: an inlet body bearing the motive flow inlet and the secondary flow inlet; a diffuser body forming the diffuser and bearing the outlet; and a motive nozzle insert forming the motive nozzle in a compartment in the inlet body, said compartment having a downstream-facing surface abutting an upstream facing surface of the motive nozzle insert.
In one or more embodiments of any of the foregoing embodiments, the ejector further comprises: a control needle shiftable between a first position and a second position; and a needle guide insert in the motive nozzle insert.
In one or more embodiments of any of the foregoing embodiments, the needle guide insert is brazed to the motive nozzle insert.
In one or more embodiments of any of the foregoing embodiments, the motive nozzle insert is brazed to the compartment.
In one or more embodiments of any of the foregoing embodiments, the inlet body is a first piece and the diffuser body is a second piece.
In one or more embodiments of any of the foregoing embodiments, the inlet body is metallic and the diffuser body is metallic.
In one or more embodiments of any of the foregoing embodiments, the inlet body is threaded to the diffuser body.
Another aspect of the disclosure involves a method for manufacturing an ejector, the ejector having: a motive flow inlet; a secondary flow inlet; an outlet; a motive nozzle; a diffuser; an inlet body bearing the motive flow inlet and the secondary flow inlet; a diffuser body forming the diffuser and bearing the outlet; and a motive nozzle insert forming the motive nozzle in a compartment in the inlet body. The method comprises inserting the motive nozzle insert into the compartment from an opening in a downstream end of the inlet body and mating the diffuser body to the downstream end of the inlet body.
In one or more embodiments of any of the foregoing embodiments, the ejector further comprises: a control needle shiftable between a first position and a second position; and a needle guide insert in the motive nozzle insert; and the method further comprises inserting the needle guide insert into the motive nozzle insert
In one or more embodiments of any of the foregoing embodiments, the method further comprises brazing the needle guide insert to the motive nozzle insert.
In one or more embodiments of any of the foregoing embodiments, the mating the diffuser body to the downstream end of the inlet body comprises threading.
In one or more embodiments of any of the foregoing embodiments, the method further comprises: brazing the motive nozzle insert to the inlet body.
The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.
Like reference numbers and designations in the various drawings indicate like elements.
The exemplary body assembly 202 includes a proximal or upstream portion 210 and a distal or downstream portion 212. As is discussed further below, the exemplary portion 210 defines an inlet body bearing the motive flow inlet 40 and the secondary flow inlet 42. The exemplary portion 202 forms a diffuser body forming the diffuser and the outlet 44. As is discussed further below, the exemplary diffuser body 212 also forms at least a portion of the mixer convergent section 114 and the mixing section 116.
The exemplary inlet body 210 also includes a mounting feature 220 for mounting the needle actuator 134. The exemplary mounting feature 220 is an internally threaded bore.
As is discussed further below, the motive nozzle insert 204 is at least partially accommodated in and mounted to the compartment 240. The motive nozzle insert 204 extends from a first or upstream end 252 to a downstream end 254 providing the outlet 110. A cylindrical base or mounting portion 256 extends downstream from the end 252 and is dimensioned to be received in the compartment section 246. In the exemplary implementation, the end 252 may abut a shoulder 258 separating the compartment sections 248 and 250. The insert 204 may be secured (e.g., press-fit or brazed in place. Downstream of the mounting portion 256, the exemplary nozzle has a short straight portion 260 extending to a tapering portion 264 externally tapering to the downstream end 254 and forming the convergent and divergent portions of the motive nozzle.
An interior surface of the nozzle insert 204 within the portions 256 and 260 is essentially cylindrical and accommodates a needle guide 270. The exemplary needle guide 270 (
In the exemplary mechanical assembly of the actuator body, the needle and actuator may be installed as a unit. Such installation may occur after mechanical assembly of the ejector to associated conduits of the vapor compression system.
Exemplary materials for the inlet body 210 and outlet body 212, insert 204, and guide 270, are metals or alloys (e.g., stainless steels, brass, aluminum and its alloys, and/or titanium and its alloys).
The use of “first”, “second”, and the like in the description and following claims is for differentiation within the claim only and does not necessarily indicate relative or absolute importance or temporal order. Similarly, the identification in a claim of one element as “first” (or the like) does not preclude such “first” element from identifying an element that is referred to as “second” (or the like) in another claim or in the description.
Where a measure is given in English units followed by a parenthetical containing SI or other units, the parenthetical's units are a conversion and should not imply a degree of precision not found in the English units.
One or more embodiments have been described. Nevertheless, it will be understood that various modifications may be made. For example, when applied to an existing basic system, details of such configuration or its associated use may influence details of particular implementations. Accordingly, other embodiments are within the scope of the following claims.
This is a continuation of Ser. No. 15/109,655, filed Jul. 4, 2016, entitled “Ejectors and Methods of Manufacture” which is a 371 U.S. national stage application of PCT/US2015/011941, filed Jan. 20, 2015, which claims benefit of U.S. Patent Application No. 61/933,766, filed Jan. 30, 2014, the disclosures of which are incorporated by reference herein in their entireties as if set forth at length.
Number | Date | Country | |
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61933766 | Jan 2014 | US |
Number | Date | Country | |
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Parent | 15109655 | Jul 2016 | US |
Child | 16448577 | US |