This application is entitled to the benefit of and incorporates by reference essential subject matter disclosed in Chinese Patent Application No. 200910127918.1 filed on Mar. 25, 2009.
1. Field of the Invention
The present invention relates to a refrigerant distributor for a heat exchanger and a heat exchanger having the refrigerant distributor.
2. Description of the Related Art
A conventional micro-channel heat exchanger 2′ generally comprises micro-channels or flat tubes 5, fins 4 disposed between the adjacent micro-channels or flat tubes 5, an inlet manifold 3 and an outlet manifold (not shown) disposed at ends of the micro-channels or flat tubes 5 respectively, and a refrigerant distributor 1′ disposed in the inlet manifold 3 as shown in
In the conventional micro-channel heat exchanger 2′, and especially in a micro-channel evaporator, since refrigerant is two-phase refrigerant containing gas and liquid, if an inappropriate refrigerant distributor is employed, the refrigerant can not be uniformly distributed to the micro-channels or flat tubes 5.
The distributor 1′ is composed of a cylindrical pipe that is inserted into the inlet manifold 3, and a plurality of outlets 8 with the same size are arranged in the cylindrical pipe at the same intervals in a longitudinal direction of the pipe as shown in
The above distributor design is disadvantageous in that the flow rate of the refrigerant gradually decreases in a refrigerant flow direction R through the distributor 1′, where a diameter (i.e., a cross-section area) of the pipe is uniform along its length. A volume flow rate of the refrigerant Q is expressed as Q=VA, where V represents a flow speed, and A represents a cross-section area of a distributor.
Therefore, the flow speed of the refrigerant gradually reduces in the refrigerant flow direction R and thus the flow rate of the refrigerant flowing from the outlets with the same size is decreased. More refrigerant is distributed from the outlets near the inlet, and less refrigerant is distributed from the outlets far from the inlet. Furthermore, after the flow speed reduces, the gas and liquid tend to be separated from each other to cause non-uniform distribution of the refrigerant.
It is an object of the present invention to provide a refrigerant distributor for a heat exchanger and a heat exchanger having the refrigerant distributor which can relatively uniformly distribute refrigerant.
In accordance with an aspect of the present application, there is provided a refrigerant distributor for a heat exchanger. The distributor comprises: a pipe having an inlet disposed generally at one end of the pipe, refrigerant flowing into the pipe through the inlet, wherein a cross-section of a flow passage within the pipe gradually decreases from the one end to the other end of the pipe.
In accordance with another aspect of the present application, there is provided a heat exchanger. The heat exchanger comprises a refrigerant distributor disposed at a side of the heat exchanger to distribute refrigerant, wherein the refrigerant distributor comprises: a pipe having an inlet disposed generally at one end of the pipe, refrigerant flowing into the pipe through the inlet, wherein a cross-section of a flow passage within the pipe gradually decreases from the one end to the other end of the pipe.
With the above configuration, refrigerant can be distributed relatively uniformly.
These and/or other aspects and advantages of the present invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings.
The embodiments are described below in order to explain the present invention, but do not pose a limitation on the scope of the invention.
A micro-channel heat exchanger 2 according to a first embodiment of the present invention comprises micro-channels or flat tubes 5, fins 4 disposed between the adjacent micro-channels or flat tubes 5, an inlet manifold 3 and an outlet manifold (not shown) disposed at ends of the micro-channels or flat tubes 5 respectively, and a refrigerant distributor 1 disposed in the inlet manifold 3 as shown in
The refrigerant distributor 1 for the heat exchanger 2 comprises: a pipe 9 having an inlet 7 disposed generally at one end of the pipe. In use, refrigerant flows into the pipe through the inlet. A cross-section of a flow passage within the pipe 9 gradually decreases from one end of the pipe to the other end.
The pipe 9 comprises a plurality of segments 91, and a cross-section area of one of the plurality of segments 91 is less than that of the preceding one of the plurality of segments 91 from one end of the pipe to the other end.
As shown in
With the above distributor, the flow rate of the refrigerant gradually decreases in the refrigerant flow direction R, but a cross-sectional area of the pipe also reduces in the refrigerant flow direction R. It can be known from the formula Q=VA that a flow speed of refrigerant is substantially uniform along the entire length of the distributor and a generally uniform amount of refrigerant is distributed from outlets having the same size. Therefore, the distributor can ensure that amounts of refrigerant passing through the respective outlets are uniform.
A heat exchanger according to a second embodiment of the present invention is the same as that of the first embodiment except in the design of the distributor 1. Only the distributor 1 is described below in detail.
The distributor 1 according to the second embodiment comprises a pipe 9. The pipe 9 is configured in such a manner that a cylindrical pipe is divided into a plurality of segments 91 and is at least partially pressed so that a cross-section of one of the plurality of segments 91 is narrower than that of the preceding one of the plurality of segments from the one end to the other end of the pipe. In other words, the cylindrical pipe is pressed to be more flat gradually in the refrigerant flow direction R. The cross-sections of the pipe have the same perimeter, but the cross-section area of the pipe gradually reduces in the refrigerant flow direction R as shown in
With the above configuration of the distributor, the flow rate of the refrigerant gradually decreases in the refrigerant flow direction R, but the cross-section area of the pipe also reduces in the refrigerant flow direction R. It can be known from the formula Q=VA that a flow speed of refrigerant is substantially uniform along the entire length of the distributor and generally uniform amount of refrigerant is distributed from the outlets with the same size. Therefore, the distributor can ensure that amounts of refrigerant passing through the respective outlets are uniform.
A micro-channel heat exchanger 2 according to a third embodiment of the present application comprises micro-channels or flat tubes 5, fins 4 disposed between the adjacent micro-channels or flat tubes 5, an inlet manifold 3 and an outlet manifold (not shown) disposed at ends of the micro-channels or flat tubes 5 respectively, and a refrigerant distributor 1 disposed in the inlet manifold 3 as shown in
The distributor 1 comprises a plurality of distributing pipes 9 (three pipes 9 are shown in
Each of the plurality of distributing pipes 9 is responsible for distributing refrigerant to the same number of the micro-channels or flat tubes 5. In
With the above configuration of the distributor, since each distributor pipe is responsible for distributing refrigerant to fewer flat tubes, a number of the distributing outlets is decreased. Therefore, the flow speed of the refrigerant within the distributor is relative uniform.
Alternatively, a plurality of distributing pipes 9 are inserted into the inlet manifold as shown in
In addition, the distributing pipe 9 may comprise any other number of pipes such as two, four, and five pipes. The plurality of pipes 9 can be arranged horizontally (as shown in
Although the above embodiments have been described, other configurations may be used to enable fluid to flow at a uniform flow speed within the distributing pipe. For example, a cone-shape pipe can be used for the distributor.
In addition, in the above embodiments, the distributing pipe 9 and the inlet manifold 3 are made of a cylindrical pipe, but they can be made of pipe having any appropriate cross-section shape such as a pipe having elliptical cross-section.
Furthermore, in the above embodiments, a micro-channel heat exchanger is described and shown in a state where the micro-channel heat exchanger stands vertically only for the purpose of convenient description and illustration. The present invention is not limited to the examples shown in the figures. In addition, the outlet manifold located on the above side of the micro-channel exchanger is omitted in the figures. The distributing pipe 9 and the inlet manifold may be disposed on the above side of the micro-channel exchanger shown in the drawings.
In addition, although a micro-channel heat exchanger is described in order to explain the present invention, the principles and concepts of the present invention can be applied to any other appropriate heat exchangers.
Furthermore, the micro-channel heat exchanger designs according to the embodiments of the present application can be used as an evaporator and the like.
Moreover, in the above embodiments, the distributing pipe 9 is inserted from one end of the inlet manifold, but with regard to the distributing pipe 9 shown in
Number | Date | Country | Kind |
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200910127918.1 | Mar 2009 | CN | national |