FOREIGN PRIORITY

This application claims priority to Chinese Patent Application No. 201910198165.7, filed Mar. 15, 2019, and all the benefits accruing therefrom under 35 U.S.C. § 119, the contents of which in its entirety are herein incorporated by reference.

FIELD OF THE INVENTION

The present disclosure relates to a refrigeration system, and more particularly, the present disclosure relates to an ejector, and a refrigeration system with an ejector.

BACKGROUND OF THE INVENTION

In commercial refrigeration systems, especially systems that require a large pressure differential, an ejector is used to improve efficiency. The ejector typically pressurizes a suction fluid by means of a high-pressure fluid and supplies mixed fluids to a compressor inlet, thereby increasing the pressure of fluid at the compressor inlet, reducing the requirements on the capacity of the compressor and improving the efficiency of the system. During the operation of the ejector, the pressure of a high-pressure fluid in a high-pressure fluid passage needs to be adjusted based on the temperature to optimize the system efficiency. In the related art, an electronic control system is usually used to control a stepper motor based on the temperature and pressure of the high-pressure fluid, thereby controlling an opening degree of a flow valve in the high-pressure fluid passage in order to achieve the optimal pressure at the current temperature. On the other hand, the system load is adjusted while maintaining the pressure.

A trans-critical refrigeration system refers to a refrigeration cycle system in which refrigerants in both subcritical and supercritical states exist. A supercritical state refers to a state where the pressure and temperature of a fluid exceed its critical pressure and critical temperature, respectively. Common trans-critical refrigeration systems for example include a system in which carbon dioxide is used as a refrigerant.

SUMMARY OF THE INVENTION

An object of the present disclosure is to solve or at least alleviate the problems existing in the related art.

In one aspect, an ejector for use in a refrigeration system is provided, which includes: a high-pressure fluid passage extending from a high-pressure fluid inlet to a mixing chamber, a flow valve for controlling a flow rate being disposed in the high-pressure fluid passage; a suction fluid passage extending from a suction fluid inlet to the mixing chamber; the mixing chamber, which includes a mixed fluid outlet; a thermal bulb disposed upstream of the flow valve, in the high-pressure fluid passage or outside the high-pressure fluid passage; and an elastic diaphragm disposed in the high-pressure fluid passage, wherein a closed cavity is on a first side of the elastic diaphragm, and the high-pressure fluid passage is on a second side of the elastic diaphragm; the thermal bulb is in communication with the closed cavity, and the thermal bulb and the closed cavity are filled with fluid; and the elastic diaphragm is associated with the flow valve so that an opening degree of the flow valve varies in response to a change in a pressure difference across two sides of the elastic diaphragm.

Optionally, in the ejector, the flow valve and the elastic diaphragm are mechanically connected.

Optionally, in the ejector, the high-pressure fluid passage includes a high-pressure fluid nozzle, the high-pressure fluid nozzle includes a constricted section, a throat portion, and a diffusion section in sequence, and the flow valve is a needle valve at the throat portion of the high-pressure fluid nozzle.

Optionally, in the ejector, a rear end of the needle valve is connected to the elastic diaphragm.

Optionally, in the ejector, the high-pressure fluid passage is further provided with a support member, and an elastic member connected between the support member and the needle valve.

Optionally, in the ejector, a position of the support member is adjustable.

Optionally, in the ejector, the suction fluid passage includes a suction chamber surrounding the high-pressure fluid nozzle.

Optionally, in the ejector, a fluid in the closed cavity is completely or partially composed of a saturated refrigerant having substantially the same composition as the fluid in the high-pressure fluid passage.

Optionally, in the ejector, a fluid in the closed cavity includes a first component having substantially the same composition as the fluid in the high-pressure fluid passage, and a second component different from the first component, and the second component functions when the first component is in a supercritical state.

Optionally, in the ejector, the mixing chamber includes a constricted section, a neck section and a diffusion section in sequence.

In another aspect, a refrigeration system is provided, which includes the ejector according to various embodiments of the present disclosure.

Optionally, the refrigeration system includes a single ejector or a plurality of ejectors connected in parallel.

Optionally, in the refrigeration system, the high-pressure fluid inlet of the ejector is connected to an outlet of a compressor via an optional regenerator, and a heat exchanger, the suction fluid inlet of the ejector is connected to an evaporator, and an outlet of the ejector is connected to a separator.

Optionally, the refrigeration system includes: a medium-temperature compressor, an outlet of which is connected to the high-pressure fluid inlet of the ejector via the heat exchanger and the optional regenerator; and a gas-liquid separator, wherein the mixed fluid outlet of the ejector is connected to the gas-liquid separator, a gas-phase outlet of the gas-liquid separator is connected to an inlet of the medium-temperature compressor, and a liquid-phase outlet of the gas-liquid separator is connected to the suction fluid inlet of the ejector via a medium-temperature expansion valve and a medium-temperature evaporator.

Optionally, in the refrigeration system, the liquid-phase outlet of the gas-liquid separator is further connected to an inlet of a low-temperature compressor via a low-temperature expansion valve and a low-temperature evaporator, and an outlet of the low-temperature compressor is connected to the inlet of the medium-temperature compressor.

