JPS6114427B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a centrifugal refrigerator. Recently, there has been a particular desire for efficient refrigerators to save energy. Conventionally, in order to improve the efficiency of a centrifugal chiller, it was necessary to improve the efficiency of the compressor, improve the evaporator or condenser, or make the compressor a multi-stage compressor and adopt an economizer cycle in the middle stage.
I could only see three ways. Among these conditions, there is a limit to the condition, so when designing a refrigerator that requires less power, in order to use the method described above, a two-stage compressor is used to create an intermediate pressure section, and an economizer cycle is used. There were many cases where it was forced to form. However, in this system, the compressor is very expensive, and in the case of throttling operation, the efficiency is poor.

The present invention eliminates the above-mentioned drawbacks of the conventional ones by boosting the pressure of the refrigerant liquid using a pump and injecting it into an impeller or diffuser to evaporate it. The purpose is to provide refrigerators.

The present invention provides a centrifugal chiller equipped with a centrifugal compressor, a condenser, and an evaporator, in which a refrigerant liquid pressurized by a pump is pumped into a casing at least in a portion between a casing shroud and a diffuser of the centrifugal compressor. This is a centrifugal chiller characterized by being equipped with a spouting part that spouts out water.

The present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 denotes an impeller driven by a motor 2 via a gear mechanism 3, and is rotatably supported in a casing 4. The casing 4 consists of an inlet 5, a casing shroud 6, a diffuser 7, a back plate 8 and a volute (not shown). 9 is a condenser, 10 is an evaporator, 11 is a cooling water pipe, 12 is a cold water pipe, 13 is a throttle device, and 14 is a pump. Spray nozzles 15 and 16 are installed on a part of the wall of the casing shroud 6 and the differential user 7.
is provided so that the refrigerant liquid pumped by the pump 14 is guided to the spray nozzles 15 and 16 through a pipe 18. As shown in FIG. 2, the arrangement of the spray nozzle 16 is such that the jet direction projected onto a plane perpendicular to the rotation axis in the direction of the jetted refrigerant liquid is approximately parallel to the gas flow path 17 exiting the impeller 1. It is arranged so that Spray nozzle 15
Although not shown, they are similarly arranged so that their projected jet direction is substantially parallel to the gas flow path in the impeller 1. 19, 20, 21, 22, 23
is the piping that connects each device.

During operation, the refrigerant gas discharged from the compressor enters the condenser 9 through the pipe 19, condenses to become a refrigerant liquid, is depressurized by the throttle device 13, is sent to the evaporator 10, and is heated by cold water. It evaporates, becomes refrigerant gas again, and is sucked into the compressor through the suction port 5. On the other hand, a part of the refrigerant liquid is diverted to a pipe 22 branched from a pipe 20 at the outlet of the condenser 9, is pressurized by a pump 14, reaches spray nozzles 15 and 16 via a pipe 18, and is sprayed into the casing 4. It is squirted. At this time, the refrigerant liquid evaporates, and the refrigerant gas discharged from the impeller 1 is cooled by the latent heat of evaporation, so that the change in the gas inside the compressor approaches an isothermal change, resulting in an effect that requires less power. .

Further, since the spray nozzles 15 and 16 are used in the ejection section, the liquid is sprayed in a finely divided form, so the number of ejection holes can be reduced and the liquid refrigerant can be efficiently evaporated. Of course, a large number of ejection holes may be provided directly on the wall of the differential user 7 or the wall of the casing shroud 6 without using a spray nozzle.

Since the directions of the spray nozzles 15 and 16 are substantially parallel to the gas flow direction, the liquid refrigerant can be efficiently evaporated.

In the above embodiment, the spray nozzle 15,
16 is provided on both the wall of the differential user 7 and the wall of the casing shroud 6, but it may be provided only on either one.

The present invention provides a centrifugal chiller equipped with a centrifugal compressor, a condenser, and an evaporator, in which a refrigerant liquid pressurized by a pump is pumped into a casing at least in a portion between a casing shroud and a diffuser of the centrifugal compressor. By having a jetting part that spouts out the air, it is possible to effectively cool the refrigerant gas that passes through the impeller and is discharged, bringing the change in gas inside the compressor closer to isothermal change and reducing the power required. High efficiency can be obtained with simple structure and low-cost equipment, reducing power consumption, and
Since the discharge temperature can be lowered, it is possible to provide a turbo chiller that can prevent thermal decomposition of the refrigerant when the condensing temperature is high, and has an extremely large effect in terms of practical use and power saving.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a flow sheet including a longitudinal section near the impeller, and FIG. 2 is a cross-sectional view of the impeller. 1... Impeller, 2... Motor, 3... Gear mechanism, 4...
Casing, 5... Suction port, 6... Casing shroud, 7... Diffuser, 8... Back plate, 9... Condenser, 10... Evaporator, 11... Cooling water pipe, 12... Cold water pipe, 13... Throttle device, 14... Pump , 15... Spray nozzle, 16... Spray nozzle, 17... Gas flow path, 18, 19, 20, 21, 22, 23... Piping.

Claims (1)

[Scope of Claims] 1. In a centrifugal refrigerator equipped with a centrifugal compressor, a condenser, and an evaporator, refrigerant liquid pressurized by a pump is supplied to at least a portion of the space between the casing shroud of the centrifugal compressor and the diffuser. A centrifugal refrigerator characterized in that it is equipped with a spouting part that spouts jets into a casing. 2. The turbo refrigerator according to claim 1, wherein the ejection part is provided on a wall surface of the differential user. 3. The turbo refrigerator according to claim 1, wherein the centrifugal compressor has an open radial impeller, and the jetting section is provided in the casing shroud. 4. Claims 1 and 2, or The centrifugal refrigerator according to item 3. 5. The turbo refrigerator according to claim 1, 2, 3, or 4, wherein the ejection portion is provided with a spray nozzle.