JP2009299609A - Ejector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase pressure rise quantity of an ejector by inhibiting mixing loss when injected fluid and sucked fluid are mixed. <P>SOLUTION: A suction passage 152d in which the sucked fluid sucked from a refrigerant suction port 152b of an ejector 15 comprises a suction space inlet 152f, a suction space 152g, and a suction space outlet 152h. Fluid passage area of the suction space inlet 152f is set smaller than an opening area of a fluid suction port 152b and fluid passage area of the suction space 152g, and a fluid passage area of the sucked space outlet 152h is set smaller than the fluid passage area of the suction space 152g. Since a velocity distribution of the sucked fluid flowing out from the suction space outlet 152h is inhibited thereby, and mixing loss when the injected fluid and the sucked fluid are mixed is inhibited, pressure rise amount of the ejector is increased. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an ejector that sucks fluid from a fluid suction port by suction action of high-speed jet fluid ejected from a nozzle.

  Conventionally, in Patent Document 1, a fluid is sucked from a fluid suction port by a suction action of a high-speed jet fluid jetted from a nozzle, and a mixed fluid of the sucked suction fluid and the jetted fluid is supplied to a pressure increasing portion (diffuser portion). An ejector for boosting the pressure is disclosed. Furthermore, in the ejector of Patent Document 1, a tapered needle that extends coaxially with the fluid passage and tapers in the fluid ejection direction is arranged in a range from the inside of the fluid passage of the nozzle to the outside of the fluid ejection port. Yes.

Thereby, the nozzle efficiency of the ejector is improved by jetting the jet fluid jetted from the fluid jet port along the surface of the needle and making the jet shape of the jet fluid an appropriate spreading shape. The nozzle efficiency is the energy conversion efficiency in the nozzle and is defined by the ratio of the velocity energy of the ejection fluid to the enthalpy difference (expansion energy) between the nozzle inlet side fluid and the fluid ejection port side fluid.
JP 2004-270460 A

  However, in the actual ejector, even if the nozzle efficiency is improved as in Patent Document 1, the pressure increase amount of the fluid in the diffuser portion cannot be increased by an amount corresponding to the improved nozzle efficiency.

  Therefore, when the present inventors investigated the cause, in order to sufficiently increase the pressure increase amount in the diffuser portion, not only the nozzle efficiency is improved, but also the energy loss caused when mixing the jet fluid and the suction fluid (Hereinafter, this energy loss is referred to as mixing loss) has been found to be suppressed.

  Here, the mixing loss will be described. The mixing loss is likely to occur when the flow direction (suction direction) when the fluid is sucked into the ejector from the fluid suction port and the ejection direction of the ejected fluid are different, for example, as in the ejector of Patent Document 1. . In other words, if the suction direction and the ejection direction are different, when the suction fluid is mixed with the ejection fluid, the flow direction of the suction fluid must be changed to the ejection direction of the ejection fluid, resulting in a velocity distribution in the suction fluid. .

  When the suction fluid having such a velocity distribution is mixed with the jet fluid, the mixed fluid of the jet fluid and the suction fluid also becomes an inhomogeneous state having the velocity distribution. When the pressure of the mixed fluid mixed inhomogeneously is increased in the diffuser unit, the amount of pressure increase is lower than in the case of increasing the pressure of the mixed fluid mixed inhomogeneously.

  The present invention has been made in view of the above points, and it is an object of the present invention to suppress the mixing loss that occurs when the jet fluid and the suction fluid are mixed, and to increase the pressure increase amount of the ejector.

In order to achieve the above object, according to the first aspect of the present invention, the nozzle (151) that ejects the fluid while reducing the pressure, and the fluid suction port that sucks the fluid by the flow of the ejected fluid ejected from the nozzle (151). (152b) and a body portion (152) in which a suction passage (152d) is formed to flow while changing the flow direction of the suction fluid sucked from the fluid suction port (152b), and flows out from the suction passage (152d). A pressure increasing unit (153) for increasing the pressure of the mixed fluid of the suction fluid and the jetting fluid,
The suction passage (152d) includes a suction space inlet (152f) through which suction fluid flows, a suction space (152g) that changes the flow direction of the suction fluid flowing in from the suction space inlet (152f), and a suction space (152g). ) Is formed by a suction space outflow port (152h) that flows out the suction fluid in the ejection direction of the ejection fluid, and the fluid passage area of the suction space inflow port (152f) is the opening area of the fluid suction port (152b) The ejector space is smaller than the fluid passage area of the suction space (152g), and the fluid passage area of the suction space outlet (152h) is smaller than the fluid passage area of the suction space (152g).

  According to this, since the fluid passage area of the suction space inlet (152f) is smaller than the opening area of the fluid suction port (152b), the suction space inlet (152f) flows into the suction space (152g). The flow rate of the suction fluid at that time can be increased more than the flow rate of the suction fluid sucked from the fluid suction port (152b). That is, the dynamic pressure of the suction fluid when flowing into the suction space (152g) from the suction space inflow port (152f) can be increased.

  Then, the dynamic pressure can cause disturbance in the fluid in the suction space (152g), and the fluid in the suction space (152g) can be mixed and homogenized. Since the flow velocity of the suction fluid after flowing into the suction space (152g) is lower than the flow velocity when flowing into the suction space (152g), the dynamic pressure of the suction fluid becomes static pressure in the suction space (152g). Converted. Therefore, the suction space (152g) acts as a pressure equalization space that equalizes the pressure of the fluid flowing out from the suction space outlet (152h) and reduces the flow velocity distribution.

  Further, since the fluid passage area of the suction space outlet (152h) is smaller than the fluid passage area of the suction space (152g), the suction space outlet (152h) is reduced before the pressure is equalized and the flow velocity distribution is reduced. It is possible to prevent the suction fluid from flowing out of the air.

  As a result, it is possible to suppress the occurrence of velocity distribution in the suction fluid flowing out from the suction space outlet (152h), and to suppress mixing loss that occurs when mixing the ejection fluid and the suction fluid. As a result, the boosting amount of the ejector can be increased.

Further, in the invention described in claim 2, a nozzle (151) that ejects the fluid by reducing the pressure, a fluid suction port (152b) that sucks the fluid by the flow of the ejected fluid ejected from the nozzle (151), and A body part (152) in which a suction passage (152d) for flowing while changing the flow direction of the suction fluid sucked from the fluid suction port (152b) is formed, and the suction fluid and the jet fluid flowing out from the suction passage (152d) And a pressurizing unit (153) for pressurizing the mixed fluid with
The fluid suction port (152b) is connected to a suction flow side pipe (14c) through which the fluid sucked into the fluid suction port (152b) flows, and the suction passage (152d) is a suction space into which the suction fluid flows. The inlet (152f), the suction space (152g) that changes the flow direction of the suction fluid that flows in from the suction space inlet (152f), and the suction fluid that flows from the suction space (152g) flows out in the jet direction of the jet fluid The suction passage outlet (152h) has a fluid passage area that is larger than the maximum fluid passage area of the suction flow side pipe (14c) and the fluid passage area of the suction space (152g). And is characterized by an ejector in which the fluid passage area of the suction space outlet (152h) is smaller than the fluid passage area of the suction space (152g). .

  According to this, since the fluid passage area of the suction space inlet (152f) is smaller than the maximum fluid passage area of the suction flow side pipe (14c), the suction space (152g) is reduced from the suction space inlet (152f). The flow rate of the suction fluid at the time of flowing in can be made higher than the flow rate of the fluid flowing through the suction flow side pipe (14c). That is, the dynamic pressure of the fluid flowing into the suction space (152g) from the suction space inflow port (152f) can be increased.

  Therefore, similarly to the first aspect of the present invention, the generation of velocity distribution in the suction fluid flowing out from the suction space outlet (152h) is suppressed, and the jet fluid and the suction fluid are mixed. Mixing loss can be suppressed. As a result, the boosting amount of the ejector can be increased.

  According to a third aspect of the present invention, in the ejector according to the second aspect, the suction flow side pipe (14c) is formed so that the fluid passage area gradually decreases toward the fluid suction port (152b). It is characterized by being.

  According to this, since the fluid passage area of the suction flow side pipe (14c) is gradually reduced toward the fluid suction port (152b), the flow rate of the fluid flowing through the suction flow side pipe (14c) The speed is gradually increased toward the suction port (152b). Therefore, the dynamic pressure of the fluid flowing into the suction space (152g) from the suction space inflow port (152f) can be increased via the fluid suction port (152b).

  According to a fourth aspect of the present invention, in the ejector according to any one of the first to third aspects, the suction space inflow port (152f) includes an orifice. According to this, it is possible to easily set the fluid passage area of the suction space inflow port (152f) to be small and to avoid the suction passage (152d) from becoming long.

  According to a fifth aspect of the present invention, in the ejector according to any one of the first to fourth aspects, the flow direction of the suction fluid sucked from the fluid suction port (152b) and the injection direction intersect perpendicularly. It is characterized by being.

  A general ejector employs a configuration in which the flow direction of the suction fluid sucked from the fluid suction port (152b) and the injection direction intersect perpendicularly as in Patent Document 1. Therefore, in such a configuration, it is very effective to be able to suppress the mixing loss that occurs when the jet fluid and the suction fluid are mixed.

  In addition, the vertical in this claim does not mean only the complete vertical, but also includes those having a slight inclination with respect to the vertical due to manufacturing errors and assembly errors within the scope of the term vertical. .

  According to a sixth aspect of the invention, in the ejector according to any one of the first to fifth aspects, the suction space (152g) is formed on the outer peripheral side of the nozzle (151). According to this, the suction fluid whose flow velocity distribution is suppressed can be evenly mixed from the entire circumference of the jet fluid, and the mixing loss can be further suppressed.

  Specifically, as in the invention described in claim 7, in the invention described in claim 1, the fluid passage area of the suction space inflow port (152f) is 0 of the opening area of the fluid suction port (152b). It may be 5 times or less. Further, as in the invention described in claim 8, in the invention described in claim 2 or 3, the fluid passage area of the suction space inlet (152f) is equal to the maximum fluid passage area of the suction flow side pipe (14c). It is good also as 0.5 times or less. Further, as in the ninth aspect of the invention, in the ejector according to any one of the first to eighth aspects, the fluid passage area of the suction space outlet (152h) is equal to the fluid passage of the suction space (152g). It is good also as 0.5 times or less of an area.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. In this embodiment, the ejector-type refrigeration cycle 10 including the ejector 15 of the present invention is applied to a heat pump water heater 1 that heats tap water and supplies hot water to a kitchen or a bath. FIG. 1 is an overall configuration diagram of a heat pump type water heater 1 according to the present embodiment.

  The heat pump hot water heater 1 includes a water circulation circuit 20 that circulates hot water in the hot water storage tank 21 and an ejector refrigeration cycle 10 as a heat pump cycle for heating the hot water. Therefore, the fluid in the present embodiment is a refrigerant that circulates in the ejector refrigeration cycle 10. In the present embodiment, carbon dioxide is used as the refrigerant, and a supercritical refrigeration cycle in which the high-pressure side refrigerant pressure is equal to or higher than the critical pressure of the refrigerant is configured.

  First, the water circulation circuit 20 will be described. The hot water storage tank 21 is a hot water tank that has a heat insulating structure and retains hot hot water for a long time, and is formed of a metal (for example, stainless steel) having excellent corrosion resistance.

  Hot water stored in the hot water storage tank 21 is discharged from a hot water outlet provided in the upper part of the hot water storage tank 21 and mixed with cold water from a tap water at a temperature control valve (not shown) to adjust the temperature, and then a kitchen, a bath, etc. Hot water is supplied. In addition, tap water is supplied from a water supply port provided in the lower part of the hot water storage tank 21.

  The water circulation circuit 20 is provided with an electric pump 22 for circulating hot water. The operation of the electric pump 22 is controlled by a control signal output from a control device (not shown). When the control device activates the electric pump 22, the hot water is circulated in the order of the electric pump 22 → the water passage 12 a of the water-refrigerant heat exchanger 12 described later → the hot water storage tank 21 → the electric pump 22.

  Next, the ejector refrigeration cycle 10 will be described. In the ejector refrigeration cycle 10, the compressor 11 sucks refrigerant, compresses it, and discharges it. In this embodiment, the electric compressor 11 drives a compression mechanism 11a having a fixed discharge capacity by an electric motor 11b. Is adopted. Specifically, various compression mechanisms such as a scroll type, a vane type, and a rolling piston type can be employed as the compression mechanism 11a.

  The operation (rotation speed) of the electric motor 11b is controlled by a control signal output from the control device, and either an AC motor or a DC motor may be adopted. And the refrigerant | coolant discharge capability of the compression mechanism 11a is changed by this rotation speed control. Therefore, the electric motor 11b of the present embodiment constitutes a discharge capacity changing unit that changes the refrigerant discharge capacity of the compression mechanism 11a.

  A refrigerant passage 12 b of the water-refrigerant heat exchanger 12 is connected to the discharge side of the compressor 11. The water-refrigerant heat exchanger 12 is a heat exchanger configured to include a refrigerant passage 12b through which a high-temperature and high-pressure refrigerant discharged from the compressor 11 passes and a water passage 12a through which hot water passes. It is a radiator that radiates the amount of heat of the high-temperature and high-pressure refrigerant discharged from the machine 11 to the hot water.

  As described above, since the ejector refrigeration cycle 10 of the present embodiment constitutes a supercritical refrigeration cycle, the refrigerant (carbon dioxide) is condensed in the refrigerant passage 12b of the water-refrigerant heat exchanger 12. Without dissipating heat in the supercritical state.

  A branch portion 13 that branches the flow of the high-pressure refrigerant flowing out from the refrigerant passage 12b is connected to the outlet side of the refrigerant passage 12b of the water-refrigerant heat exchanger 12. The branch portion 13 has a three-way joint structure having three inflow / outflow ports, and one of the inflow / outflow ports is a refrigerant inflow port, and two are refrigerant outflow ports. Such a three-way joint may be constituted by joining pipes having different pipe diameters, or may be constituted by providing a plurality of refrigerant passages having different passage diameters in a metal block or a resin block.

  Further, a first refrigerant pipe 14a that connects the branch portion 13 and a nozzle 151 inlet side of an ejector 15 described later is connected to one refrigerant outlet of the branch portion 13, and a branch portion is connected to the other refrigerant outlet. A second refrigerant pipe 14b is connected to 13 and an electric expansion valve 17 inlet side described later. The first refrigerant pipe 14a is a drive flow side pipe through which the drive flow of the ejector 15 flows.

  The ejector 15 functions as a refrigerant decompression unit, and also functions as a momentum transport pump that circulates the refrigerant by the suction action of the injection refrigerant injected from the nozzle 151. The detailed configuration of the ejector 15 will be described with reference to FIG. FIG. 2 is an axial sectional view of the ejector 15.

  As shown in FIG. 2, the ejector 15 of this embodiment includes a nozzle 151, a body part 152, a diffuser part 153, a needle 154, a drive part 155, and the like. First, the nozzle 151 is an isentropic decompression jet that injects the refrigerant that has flowed into the inside through the first refrigerant pipe 14a, and performs cutting on a substantially cylindrical metal (for example, stainless steel). Is formed by.

  Specifically, the nozzle 151 is formed in a shape in which two cylindrical members having different diameters are coaxially coupled, and the outer peripheral surface of the large-diameter portion 151 a on the larger diameter side is press-fitted and fixed to the body portion 152. ing. Furthermore, the large-diameter portion 151a is provided with a nozzle inlet 151d that allows the refrigerant flowing in through the first refrigerant pipe 14a to flow into the refrigerant passage 151c formed in the nozzle 151.

  The refrigerant passage 151c is formed so that the refrigerant flows from the large diameter portion 151a side to the small diameter portion 151b side. Further, the downstream side (small diameter portion 151b side) portion of the refrigerant passage 151c extends in the axial direction of the nozzle 151 so that the refrigerant passage area gradually decreases in the refrigerant flow direction. Thereby, the refrigerant | coolant which distribute | circulates the refrigerant path 151c is pressure-reduced, and is injected to the arrow 100 direction from the refrigerant | coolant injection port 151e formed in the most downstream part of the refrigerant path 151c.

  A needle 154 that is displaced in the axial direction of the nozzle 151 and changes the refrigerant passage area of the refrigerant passage 151c is disposed inside the refrigerant passage 151c. The needle 154 is a needle-like member extending coaxially with the nozzle 151, and is formed by cutting a cylindrical metal (for example, stainless steel).

  Further, a tapered tip end portion that tapers in the coolant injection direction is formed at the end portion of the needle 154 on the coolant injection port 151e side, and this tip end portion reaches the downstream side of the coolant injection port 151e. Extends to range. Therefore, when the needle 154 is displaced, not only the refrigerant passage area of the refrigerant passage 151c but also the opening area of the refrigerant injection port 151e changes. On the other hand, a male screw portion connected to the drive portion 155 is provided at the opposite end of the needle 154.

  The drive unit 155 is a motor actuator that displaces and drives the needle 154, and includes a coil 155a, a rotor 155b, and a can 155c. The coil 155a generates a rotating magnetic force that rotates the rotor 155b around the axis of the nozzle 151 by a control signal output from the control device.

  The rotor 155b is formed with a female screw portion that is screwed into the screw portion of the needle 154. Accordingly, when the rotor 155b rotates, the male threaded portion of the needle 154 is sent out as the female threaded portion rotates, and the entire needle 154 is displaced in the axial direction of the nozzle 151. The can 153 c is a housing member that houses the rotor 155 b and functions as a fixing member that fixes the driving unit 155 to the body unit 152.

  Next, the body portion 152 is fixed with the nozzle 151, the drive portion 155, and the like, and various opening holes through which the refrigerant flows in and out, and various refrigerants through which the refrigerant flowing from these opening holes flows. A passage or the like is formed, and is formed by cutting and drilling a cylindrical metal (for example, stainless steel).

  The various opening holes include a refrigerant inlet 152a that allows the first refrigerant pipe 14a and the nozzle inlet 152d of the nozzle 151 to communicate with each other, a refrigerant suction port 152b that sucks a downstream side refrigerant, which will be described later, and a refrigerant suction port. A refrigerant outlet 152c is formed through which a mixed refrigerant of the suction refrigerant sucked from the port 152b and the jet refrigerant jetted from the refrigerant jet port 151e of the nozzle 151e flows out.

  The refrigerant inlet 152 a is disposed on the outer peripheral side of the large diameter portion 151 a of the nozzle 151 and opens in a direction perpendicular to the axial direction of the nozzle 151. The first refrigerant pipe 14a is connected to the refrigerant inlet 152a.

  The refrigerant suction port 152 b is disposed on the outer peripheral side of the small diameter portion 151 b of the nozzle 151 and opens in a direction perpendicular to the axial direction of the nozzle 151. Therefore, the flow direction of the suction fluid sucked from the refrigerant suction port 152b and the injection direction of the injection refrigerant intersect perpendicularly. Further, a third refrigerant pipe 14c that is a suction flow side pipe connected to the outlet side of the suction side evaporator 18 is connected to the refrigerant suction port 152b.

  The refrigerant outlet 152 c is disposed coaxially with the nozzle 151 and opens in the axial direction of the nozzle 151. A diffuser portion 153 is connected to the refrigerant outlet 152c. The first refrigerant pipe 14a, the third refrigerant pipe 14c, and the diffuser part 153 are made of metal (for example, copper) pipes, and are joined to the body part 152 by means such as brazing. Yes.

  In addition, as various refrigerant passages, a suction passage 152d that guides the suction refrigerant sucked from the refrigerant suction port 152b to the refrigerant injection port 151e side of the nozzle 151, and a suction passage 152d that is provided continuously with the suction passage 152d, the mixed refrigerant is used as the A mixing passage 152e leading to the outflow port 152c is formed.

  The suction passage 152d has a suction space inlet 152f through which the suction refrigerant sucked from the refrigerant suction port 152b flows, a suction space 152g through which the suction refrigerant flowing from the suction space inlet 152f flows, and a suction refrigerant from the suction space 152g. It is constituted by a suction space outlet 152h to be discharged.

  The suction space inlet 152f opens in the same direction as the refrigerant suction port 152b, and is formed so that the refrigerant passage area is smaller than the opening area of the refrigerant suction port 152b. According to the study of the present inventor, it has been found that it is desirable that the fluid passage area of the suction space inflow port 152f is specifically 0.5 times or less the opening area of the fluid suction port 152b.

  As is clear from FIG. 2, the fluid passage area of the suction space inlet 152f is smaller than the maximum refrigerant passage area of the suction flow side pipe 14c. Furthermore, in this embodiment, the suction space inflow port 152f is configured by an orifice. Such a suction space inflow port 152f may be configured by directly forming an orifice in the body portion 152, or may be configured by fitting an orifice formed by a separate member into the suction space inflow port 152f.

  The suction space 152g is a cylindrical space formed on the outer peripheral side of the small diameter portion 151b of the nozzle 151, and is a space through which the suction refrigerant flowing from the suction space inlet 152f flows while changing the flow direction. The suction space 152g is formed such that the refrigerant passage area is larger than the refrigerant passage area of the suction space inlet 152f.

  The refrigerant passage area of the suction space 152g is a cross-sectional area of the suction space 152g in a cross section perpendicular to the flowing direction of the flowing refrigerant. For this reason, when the flow direction of the suction refrigerant flowing through the suction space 152g changes, the refrigerant passage area of the suction space 152g also changes.

  Therefore, in this embodiment, the minimum refrigerant passage area among the refrigerant passage areas of the suction space 152g is larger than the refrigerant passage area of the suction space inlet 152f. In other words, the refrigerant passage area of the suction space inlet 152f is smaller than the minimum refrigerant passage area of the suction space 152g. Specifically, it is desirable that the fluid passage area of the suction space inlet 152f be 0.5 times or less than the maximum fluid passage area of the suction flow side pipe 14c.

  The suction space outlet 152h opens in the axial direction of the nozzle 151, that is, in the injection direction of the injection refrigerant (arrow 100 direction) injected from the refrigerant injection port 151e, and flows out the refrigerant in the suction space 152g in the injection direction. Let

  Furthermore, the suction space outlet 152h is formed such that the refrigerant passage area is smaller than the minimum refrigerant passage area of the suction space 152g. Specifically, the fluid passage area of the suction space outlet 152h is desirably 0.5 times or less than the minimum fluid passage area of the suction space 152g.

  Note that the tip of the small diameter portion 151b of the nozzle 151 passes through the center of the suction space outlet 152h. Therefore, the refrigerant injection port 151e opens toward the downstream side of the refrigerant flow with respect to the suction space outflow port 152h, and the suction space outflow port 152h is formed in a donut shape (ring shape).

  The diffuser portion 153 is a pressure increasing portion that decelerates the refrigerant flow and increases the refrigerant pressure, and is formed into a shape that gradually increases the refrigerant passage area by plastically deforming a metal pipe (copper pipe). Thereby, the effect | action which converts the velocity energy of a refrigerant | coolant into pressure energy is fulfilled. More specifically, straight portions where the refrigerant passage area does not change are formed on the inlet side and the outlet side of the diffuser portion 153. Further, as shown in FIG. 1, an outlet side evaporator 16 is connected to the outlet side of the diffuser portion 153.

  The outflow side evaporator 16 is a heat exchanger for heat absorption that evaporates the refrigerant and exerts an endothermic effect by exchanging heat between the refrigerant flowing out of the diffuser portion 153 and the outdoor air blown from the blower fan 16a. The blower fan 16a is an electric blower in which the rotation speed (the amount of blown air) is controlled by a control voltage output from the control device. A refrigerant suction port of the compressor 11 is connected to the outlet side of the outflow side evaporator 16.

  Next, an electric expansion valve 17 is connected to the second refrigerant pipe 14b through which the other refrigerant branched at the branch portion 13 flows. The electric expansion valve 17 is a decompression unit that decompresses and expands the refrigerant flowing into the second refrigerant pipe 14b. The operation of the electric expansion valve 17 is controlled by a control signal output from the control device.

  A suction side evaporator 18 is connected to the downstream side of the electric expansion valve 17. The suction-side evaporator 18 evaporates the refrigerant by exchanging heat between the refrigerant decompressed and expanded by the electric expansion valve 17 and the outdoor air that has been blown from the blower fan 16a and has passed through the outflow-side evaporator 16. This is an endothermic heat exchanger that exerts an endothermic effect. A refrigerant suction port 152b of the ejector 15 is connected to the outlet side of the suction side evaporator 18 via the third refrigerant pipe 14c described above.

  In this embodiment, the outflow side evaporator 16 and the suction side evaporator 18 are constituted by a heat exchanger having a fin-and-tube structure, and the heat exchange fins of the outflow side evaporator 16 and the suction side evaporator 18 are shared. Yes. And the tube structure which distribute | circulates the refrigerant | coolant which flowed out from the ejector 15 and the tube structure which distribute | circulates the refrigerant | coolant which flowed out from the electric expansion valve 17 are provided mutually independently, and the outflow side evaporator 16 and the suction side evaporator 18 are provided. It is constructed as a unitary structure.

  Therefore, the outdoor air blown by the above-described blower fan 16a flows as indicated by an arrow 200 and is first absorbed by the outflow side evaporator 16 and then absorbed by the suction side evaporator 18. ing.

  That is, the outflow side evaporator 16 and the suction side evaporator 18 are arranged in series with respect to the flow direction of the outdoor air (in the direction of the arrow 200) that exchanges heat with the refrigerant passing through the inside. Of course, the outflow side evaporator 16 and the suction side evaporator 18 may be constituted by two separate evaporators and arranged in series in the air flow direction (direction of arrow 200).

  Next, an outline of the electric control unit of the present embodiment will be described. The control device includes a known microcomputer including a CPU, a ROM, a RAM, and the like, and peripheral circuits thereof. The output side includes an electric motor 11b of the compressor 11, a drive unit 155 of the ejector 15, a blower fan 16a, Various actuators such as an electric expansion valve 17 and an electric pump 22 are connected to control the operation of these devices.

  Further, on the input side of the control device, a hot water temperature sensor for detecting the temperature of hot water at the outlet of the water passage 12a of the water-refrigerant heat exchanger 12, and an outdoor air temperature (outside air temperature) detected by the blower fan 16a are detected. A sensor group for various controls such as an outdoor air temperature sensor is connected. Further, an operation panel (not shown) is connected to the input side of the control device, and an operation signal for hot water heater operation / stop, a hot water supply temperature setting signal for the water heater, and the like are input to the control device.

  Next, the operation of the heat pump type water heater 1 of the present embodiment in the above configuration will be described. When the hot water heater operation signal of the operation panel is input to the control device in a state where power is supplied to the heat pump hot water heater 1 from the outside, the control device executes a program stored in the ROM in advance. Thereby, the above-mentioned various actuators 11b, 155, 16a, 17, and 22 are operated.

  The high-temperature and high-pressure refrigerant discharged from the compressor 11 flows into the refrigerant passage 12b of the water-refrigerant heat exchanger 12, and the hot water and heat flow into the water passage 15a from the lower side of the hot water storage tank 21 by the electric pump 22. Exchange. Thereby, the hot water is heated, and the heated hot water is stored on the upper side of the hot water storage tank 21.

  The high-pressure refrigerant that has flowed out of the water-refrigerant heat exchanger 12 flows into the branch portion 13, and one refrigerant branched at the branch portion 13 flows into the nozzle 151 of the ejector 15 via the first refrigerant pipe 14a. . The refrigerant that has flowed into the nozzle 151 is decompressed in an isentropic manner and is injected as a high-speed injection refrigerant from the refrigerant injection port 151e.

  At this time, the drive unit 155 of the ejector 15 causes the refrigerant passage 151c and the refrigerant injection port 151e of the ejector 15 so that the superheat degree of the refrigerant sucked by the compressor 11 becomes a predetermined value by a control signal output from the control device. The refrigerant passage area is changed. Thereby, the problem of the liquid back to the compressor 11 can be avoided.

  Then, the refrigerant flowing out of the suction side evaporator 18 is sucked from the refrigerant suction port 152b by the suction action of the injection refrigerant. Further, on the inlet side of the mixing passage 152e and the diffuser portion 153, the injection refrigerant injected from the refrigerant injection port 151e and the suction refrigerant sucked from the refrigerant suction port 152b are mixed and flow into the diffuser portion 153.

  In the diffuser portion 153, the refrigerant pressure increases because the velocity energy of the refrigerant is converted into pressure energy due to the expansion of the passage area. The refrigerant that has flowed out of the diffuser portion 153 of the ejector 15 flows into the outflow side evaporator 16, absorbs heat from the outdoor air blown from the blower fan 16a, and evaporates. The refrigerant flowing out from the outflow side evaporator 16 is sucked into the compressor 11 and compressed again.

  On the other hand, the other refrigerant branched at the branch portion 13 is decompressed and expanded by the electric expansion valve 17 and flows into the suction-side evaporator 18. The refrigerant that has flowed into the suction side evaporator 18 absorbs heat from the outside air that is blown from the blower fan 16 a and cooled by the outflow side evaporator 16, and evaporates. Further, the refrigerant flowing out from the suction side evaporator 18 is sucked into the ejector 15 from the refrigerant suction port 152b.

  At this time, the electric expansion valve 17 changes the throttle passage area (valve opening) so that the high-pressure side refrigerant pressure of the cycle approaches the target high pressure by the control signal output from the control device. The target high pressure is a value that is determined so that the coefficient of performance (COP) of the cycle becomes substantially maximum based on the temperature of the refrigerant flowing out of the refrigerant passage 12b of the water-refrigerant heat exchanger 12. Thereby, the ejector-type refrigeration cycle 10 can be operated while exhibiting a high COP.

  Further, in the ejector refrigeration cycle 10 of the present embodiment, when the refrigerant exerts an endothermic effect in the outflow side evaporator 16 and the suction side evaporator 18, the refrigerant evaporation pressure in the outflow side evaporator 16 is changed by the diffuser unit 153. On the other hand, since the suction side evaporator 18 is connected to the refrigerant suction port 152b, the refrigerant evaporation pressure in the suction side evaporator 18 can be set to the lowest pressure immediately after the pressure reduction of the nozzle 151.

  Accordingly, the refrigerant evaporation pressure (refrigerant evaporation temperature) in the suction-side evaporator 18 can be made lower than the refrigerant evaporation pressure (refrigerant evaporation temperature) in the outflow side evaporator 16. As a result, the temperature difference between the refrigerant evaporation temperature in the outflow side evaporator 16 and the suction side evaporator 18 and the outside air blown from the blower fan 16a can be secured, and the refrigerant can efficiently exhibit the endothermic effect.

  Furthermore, in the present embodiment, the suction passage 152d is constituted by the suction space inflow port 152f, the suction space 152g, and the suction space outflow port 152h, so that the following excellent effects can be obtained.

  That is, since the refrigerant passage area of the suction space inlet 152f is smaller than the opening area of the refrigerant suction port 152b, the flow rate of the suction refrigerant when flowing into the suction space 152g from the suction space inlet 152f is expressed as the refrigerant suction port. The flow rate of the suction refrigerant sucked from 152b can be increased. That is, the dynamic pressure of the suction refrigerant when flowing from the suction space inlet 152f to the suction space 152g can be increased.

  Then, the dynamic pressure can cause disturbance in the fluid in the suction space 152g, and the fluid in the suction space 152g can be mixed and homogenized. Since the flow velocity of the suction fluid after flowing into the suction space 152g is lower than the flow velocity when flowing into the suction space 152g, the dynamic pressure of the suction fluid is converted into a static pressure in the suction space 152g. Accordingly, the suction space 152g acts as a pressure equalization space that equalizes the pressure of the fluid flowing out from the suction space outlet 152h and reduces the flow velocity distribution.

  Further, since the fluid passage area of the suction space outlet 152h is smaller than the fluid passage area of the suction space 152g, the suction fluid flows out from the suction space outlet 152h before the pressure is equalized and the flow velocity distribution is reduced. Can be suppressed.

  As a result, it is possible to suppress the occurrence of velocity distribution in the suction refrigerant flowing out from the suction space outlet 152h, and to suppress the mixing loss that occurs when the injection refrigerant and the suction refrigerant are mixed. As a result, the boosting amount of the ejector can be increased and the driving power of the compressor 11 can be reduced, so that a further COP improvement effect can be obtained as a whole cycle.

  Further, since the suction space inlet 152f is constituted by an orifice, the flow rate of the suction refrigerant when flowing into the suction space 152g from the suction space inlet 152f is greater than the flow rate of the suction refrigerant sucked from the refrigerant suction port 152b. Therefore, the length of the suction passage 152d can be prevented from increasing.

  In addition, since the suction space 152g is formed on the outer peripheral side of the nozzle 151, the suction refrigerant whose flow velocity distribution is suppressed can be evenly mixed from the entire outer periphery of the injection refrigerant. Therefore, mixing loss can be effectively suppressed.

  Further, the general ejector employs a configuration in which the flow direction of the suction refrigerant sucked from the refrigerant suction port 152b and the injection direction intersect perpendicularly as in the present embodiment. In such a configuration, it is extremely effective to be able to suppress the mixing loss that occurs when the injection refrigerant and the suction refrigerant are mixed.

(Second Embodiment)
In the first embodiment, an example has been described in which the suction space inlet 152f is configured as an orifice, thereby increasing the flow rate of the suction refrigerant when flowing into the suction space 152g from the suction space inlet 152f. In the embodiment, as shown in FIG. 3, the suction flow side pipe 14c is formed so that the refrigerant passage area gradually decreases toward the refrigerant suction port 152b.

  Therefore, also in this embodiment, the refrigerant passage area of the suction space inflow port 152f is smaller than the maximum refrigerant passage area of the suction flow side pipe 14c. Other configurations are the same as those of the first embodiment. FIG. 3 is a sectional view in the axial direction of the ejector 15 of the present embodiment, and the same or equivalent parts as in the first embodiment are denoted by the same reference numerals.

  Therefore, when the heat pump type water heater 1 of this embodiment is operated, the flow rate of the refrigerant flowing through the suction flow side pipe 14c can be gradually increased toward the refrigerant suction port 152b. That is, the dynamic pressure of the refrigerant flowing into the suction space 152g from the suction space inlet 152f can be increased.

  As a result, similarly to the first embodiment, the speed distribution is suppressed from being generated in the suction refrigerant flowing out from the suction space outflow port 152h, and the mixing loss caused when mixing the injection refrigerant and the suction refrigerant is suppressed. can do. Furthermore, since the flow rate of the refrigerant flowing through the suction flow side pipe 14c is gradually increased, the generation of noise can be suppressed as compared with the case where the flow rate of the refrigerant is rapidly increased.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be variously modified as follows.

  (1) In the above-described embodiment, the example in which the flow direction of the suction refrigerant sucked from the refrigerant suction port 152b and the injection direction (arrow 100 direction) of the injection refrigerant intersect perpendicularly has been described. The flow direction of the suction refrigerant sucked from the refrigerant suction port 152b may be different from the injection direction of the injection refrigerant.

  That is, in the suction space 152g, the suction refrigerant flowing from the suction space inlet 152f changes the flow direction and is injected in the injection direction from the suction space outlet 152h. Obtainable.

  (2) In the above-described embodiment, during normal operation, the refrigerant passage area of the nozzle 151 is changed so that the superheat degree of the outlet side refrigerant of the outflow side evaporator 16 becomes a predetermined target superheat degree, and the high pressure side of the cycle Although the example in which the throttle passage area of the electric expansion valve 17 is changed so that the refrigerant pressure becomes the target high pressure has been described, of course, the reverse may be possible.

  That is, the throttle passage area of the electric expansion valve 17 is changed so that the degree of superheat of the outlet side refrigerant of the outlet evaporator 16 becomes a predetermined target degree of superheat so that the high pressure side refrigerant pressure of the cycle becomes the target high pressure. Further, the throttle passage area of the nozzle 151 may be changed.

  (3) In the above-described embodiment, an example in which carbon dioxide is employed as the refrigerant has been described, but the type of refrigerant is not limited to this. For example, a hydrocarbon refrigerant, a normal chlorofluorocarbon refrigerant, or the like may be employed. The ejector refrigeration cycle of the present invention may be configured as a subcritical refrigeration cycle in which the high-pressure side refrigerant pressure does not exceed the critical pressure of the refrigerant.

  (4) In the above-described embodiment, an example in which an electric compressor is employed as the compressor 11 has been described. However, the format of the compressor 11 is not limited to this. For example, you may employ | adopt the engine drive type compressor which uses an engine etc. as a drive source. Further, as the compression mechanism, not only a fixed capacity type compression mechanism but also a variable capacity type compression mechanism may be adopted.

  (5) In the above-described embodiment, the ejector 15 that employs a so-called variable nozzle configured to change the refrigerant passage area as the nozzle 151 has been described. However, the ejector that employs a fixed nozzle with a fixed refrigerant passage area It may be 15.

  (6) In the above-described embodiment, the example in which the ejector refrigeration cycle 10 of the present invention is applied to the heat pump type hot water heater 1 has been described, but the application of the present invention is not limited thereto. For example, the present invention may be applied to a stationary air conditioner, a vehicle air conditioner, and the like. In this case, the outflow side evaporator 16 and the suction side evaporator 18 may be indoor heat exchangers that cool the indoor blown air, and the radiator may be an outdoor heat exchanger that exchanges heat between the high-pressure refrigerant and the atmosphere.

It is a whole block diagram of the ejector-type refrigerating cycle of 1st Embodiment. It is sectional drawing of the ejector of 1st Embodiment. It is sectional drawing of the ejector of 2nd Embodiment.

Explanation of symbols

151 Nozzle 152 Body portion 152b Refrigerant suction port 152d Suction passage 152f Suction space inlet 152g Suction space 152h Suction space outlet 152 Body portion 153 Diffuser portion 14c Suction flow side piping

Claims (9)

A nozzle (151) for depressurizing and injecting fluid;
A fluid suction port (152b) that sucks fluid by the flow of the ejected fluid ejected from the nozzle (151), and suction that circulates while changing the flow direction of the suction fluid sucked from the fluid suction port (152b) A body portion (152) in which a passage (152d) is formed;
A pressure increasing unit (153) for increasing the pressure of the mixed fluid of the suction fluid and the jet fluid flowing out from the suction passage (152d);
The suction passage (152d) includes a suction space inlet (152f) for allowing the suction fluid to flow in, a suction space (152g) for changing the flow direction of the suction fluid flowing from the suction space inlet (152f), and A suction space outlet (152h) that causes the suction fluid that has flowed from the suction space (152g) to flow in the jet direction of the jet fluid;
The fluid passage area of the suction space inlet (152f) is smaller than the opening area of the fluid suction port (152b) and the fluid passage area of the suction space (152g),
The ejector according to claim 1, wherein a fluid passage area of the suction space outlet (152h) is smaller than a fluid passage area of the suction space (152g). A nozzle (151) for depressurizing and injecting fluid;
A fluid suction port (152b) that sucks fluid by the flow of the ejected fluid ejected from the nozzle (151), and suction that circulates while changing the flow direction of the suction fluid sucked from the fluid suction port (152b) A body portion (152) in which a passage (152d) is formed;
A pressure increasing unit (153) for increasing the pressure of the mixed fluid of the suction fluid and the jet fluid flowing out from the suction passage (152d);
The fluid suction port (152b) is connected to a suction flow side pipe (14c) through which the fluid sucked into the fluid suction port (152b) flows.
The suction passage (152d) includes a suction space inlet (152f) for allowing the suction fluid to flow in, a suction space (152g) for changing the flow direction of the suction fluid flowing from the suction space inlet (152f), and A suction space outlet (152h) that causes the suction fluid that has flowed from the suction space (152g) to flow in the jet direction of the jet fluid;
The fluid passage area of the suction space inlet (152f) is smaller than the maximum fluid passage area of the suction flow side pipe (14c) and the fluid passage area of the suction space (152g),
The ejector according to claim 1, wherein a fluid passage area of the suction space outlet (152h) is smaller than a fluid passage area of the suction space (152g).   The ejector according to claim 2, wherein the suction flow side pipe (14c) is formed so that a fluid passage area gradually decreases toward the fluid suction port (152b).   The ejector according to any one of claims 1 to 3, wherein the suction space inflow port (152f) includes an orifice.   The ejector according to any one of claims 1 to 4, wherein a flow direction of the suction fluid sucked from the fluid suction port (152b) and the ejection direction intersect each other perpendicularly.   The ejector according to any one of claims 1 to 5, wherein the suction space (152g) is formed on an outer peripheral side of the nozzle (151).   The ejector according to claim 1, wherein a fluid passage area of the suction space inlet (152f) is 0.5 times or less of an opening area of the fluid suction port (152b).   The ejector according to claim 2 or 3, wherein a fluid passage area of the suction space inlet (152f) is 0.5 times or less of a maximum fluid passage area of the suction flow side pipe (14c).   The fluid passage area of the suction space outlet (152h) is 0.5 times or less of the fluid passage area of the suction space (152g), according to any one of claims 1 to 8, Ejector.

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