CN107576211A - A kind of cross flow heat exchanger and Multi-stage heating heat pump - Google Patents

Abstract

The invention provides a cross-flow heat exchanger, which includes a shell, several heat exchange tubes and several heat exchange elbows, the heat exchange tubes are arranged in the shell, and the heat exchange elbows are arranged in the shell on the outer wall of the body; the heat exchange tubes include a first heat exchange tube and a second heat exchange tube, and the heat exchange elbow includes a first heat exchange elbow and a second heat exchange elbow, and the first heat exchange tube The heat pipe communicates with the first heat exchange elbow and forms a first branch, the second heat exchange tube communicates with the second heat exchange elbow and forms a second branch, and the first branch Alternately arranged with the second branch along the up-down direction of the housing. The embodiments of the present invention can effectively improve the heat exchange efficiency of the heat exchangers of the parallel heat pump system when only one system is running and avoid high pressure problems. The embodiment of the present invention also provides a multi-stage heating heat pump system.

Description

A cross-flow heat exchanger and multi-stage heating heat pump system

technical field

The invention relates to the technical field of heat pumps, in particular to a cross-flow heat exchanger and a multi-stage heating heat pump system.

Background technique

At present, the operation of the heat pump dual system is operated by two independent systems, and each of the two independent systems works through a heat exchanger. When one of the independent systems in the heat pump dual system is unloaded, the heat pump dual system is operated by the other independent system. , resulting in higher energy consumption for the overall operation of the heat pump dual system.

The parallel heat pump system in the prior art can better solve the problem of high energy consumption in the overall operation of the dual heat pump system. However, the two systems of the parallel heat pump system operate in the same heat exchanger. The refrigerant flows in the heat exchanger for heat exchange. Since the heat exchanger is designed to flow up and down in the two systems, when only one system is running in the parallel heat pump system, the heat exchange area of the heat exchanger will be It will reduce and cause the heat exchange efficiency of the heat exchanger to be low, and at the same time, it is prone to the problem of high pressure reported by the system.

Contents of the invention

The embodiment of the present invention provides a cross-flow heat exchanger and a multi-stage heating heat pump system to solve the technical problem that the heat exchange efficiency is low and the system reports high pressure when only one heat exchanger in the parallel heat pump system is running, and improve the efficiency of the parallel heat pump system. The system's heat exchangers are efficient when only one system is running and avoid high pressure problems.

In order to achieve the above object, an embodiment of the present invention provides a cross-flow heat exchanger on the one hand, including a shell, several heat exchange tubes and several heat exchange elbows, the heat exchange tubes are arranged in the shell, and the The heat exchange elbow is arranged on the outer wall of the housing; the heat exchange tube includes a first heat exchange tube and a second heat exchange tube, and the heat exchange elbow includes a first heat exchange elbow and a second heat exchange tube A thermal elbow, the first heat exchange tube communicates with the first heat exchange elbow and forms a first branch, the second heat exchange tube communicates with the second heat exchange elbow and forms a second branch road, and the first branch and the second branch are arranged alternately along the up-down direction of the housing.

Preferably, the first heat exchange elbow and the second heat exchange elbow are evenly distributed on the outer side wall of the housing.

Preferably, it also includes a first air inlet pipe, a first liquid outlet pipe, a second air inlet pipe and a second liquid outlet pipe; the inlet port of the first branch is communicated with the first air inlet pipe, and the first branch The outlet end of the channel is communicated with the first liquid outlet pipe, the inlet end of the second branch is communicated with the second air inlet pipe, and the outlet end of the second branch is communicated with the second liquid outlet pipe .

Preferably, the first air intake pipe is provided with a first thin air intake pipe and several first air outlet thin pipes for introducing refrigerant gas, and the first air intake pipe communicates with the first air intake thin pipe, The first air inlet pipe communicates with the inlet end of the first branch through several first air outlet thin pipes; the first liquid outlet pipe is provided with a first liquid outlet thin pipe for refrigerant liquid to flow out and A plurality of first thin liquid inlet tubes, the first liquid outlet pipe is in communication with the first liquid outlet thin tube, and the first liquid outlet pipe is connected to the first shunt through several of the first liquid inlet thin tubes The outlet port is connected.

Preferably, the second air intake pipe is provided with a second air intake thin pipe for introducing refrigerant gas and several second air outlet thin pipes, and the second air intake pipe communicates with the second air intake thin pipe, The second air inlet pipe communicates with the inlet end of the second branch through several second air outlet thin pipes; the second liquid outlet pipe is provided with a second liquid outlet thin pipe for refrigerant liquid to flow out and Several second thin liquid inlet tubes, the second liquid outlet pipe communicates with the second liquid outlet thin tube, and the second liquid outlet pipe connects with the second branch through several second liquid inlet thin tubes The outlet port is connected.

Preferably, several heat exchange elbows are arranged obliquely on the outer wall of the housing, and the first heat exchange elbow and the second heat exchange elbow are arranged obliquely.

Preferably, several heat exchange tubes are arranged in parallel, and the first heat exchange tube and the second heat exchange tube are arranged in parallel.

Preferably, fins are also included, the fins are arranged in the casing, and the fins are connected to the outer side walls of the heat exchange tubes.

Another aspect of the embodiment of the present invention provides a multi-stage heating heat pump system, including a first system, a second system, a third system, a fourth system, a first cross-flow heat exchanger, and a second cross-flow heat exchanger, Both the first cross-flow heat exchanger and the second cross-flow heat exchanger are the above-mentioned cross-flow heat exchangers;

The first system includes a first compressor, a first throttling device, and a first evaporator, the outlet end of the first compressor communicates with the first inlet pipe of the first cross-flow heat exchanger, and the The first outlet pipe of the first cross-flow heat exchanger communicates with the first port of the first throttling device, and the second port of the first throttling device communicates with the first port of the first evaporator , the second port of the first evaporator communicates with the inlet port of the first compressor;

The second system includes a second compressor, a second throttling device, and a second evaporator, the outlet end of the second compressor communicates with the first inlet pipe of the second cross-flow heat exchanger, and the The first outlet pipe of the second cross-flow heat exchanger communicates with the first port of the second throttling device, and the second port of the second throttling device communicates with the first port of the second evaporator , the second port of the second evaporator communicates with the inlet end of the second compressor;

The third system includes a third compressor, a third throttling device, and a third evaporator, the outlet end of the third compressor communicates with the second intake pipe of the first cross-flow heat exchanger, and the The second outlet pipe of the first cross-flow heat exchanger communicates with the first port of the third throttling device, and the second port of the third throttling device communicates with the first port of the third evaporator , the second port of the third evaporator communicates with the inlet port of the third compressor;

The fourth system includes a fourth compressor, a fourth throttling device, and a fourth evaporator, the outlet end of the fourth compressor communicates with the second intake pipe of the second cross-flow heat exchanger, and the The second liquid outlet pipe of the second cross-flow heat exchanger communicates with the first port of the fourth throttling device, and the second port of the fourth throttling device communicates with the first port of the fourth evaporator , the second port of the fourth evaporator communicates with the inlet end of the fourth compressor.

Preferably, the first cross-flow heat exchanger and the second cross-flow heat exchanger are arranged at the air outlet, and the first cross-flow heat exchanger and the second cross-flow heat exchanger are arranged in parallel and against each other.

Compared with the prior art, the beneficial effect of the embodiments of the present invention is that the embodiments of the present invention provide a cross-flow heat exchanger, including a shell, several heat exchange tubes and several heat exchange elbows, the heat exchange tubes The heat exchange elbow is arranged on the outer wall of the housing; the heat exchange tube includes a first heat exchange tube and a second heat exchange tube, and the heat exchange elbow includes a first heat exchange tube A heat exchange elbow and a second heat exchange elbow, the first heat exchange tube communicates with the first heat exchange elbow and forms a first branch, the second heat exchange tube communicates with the second heat exchange elbow The hot elbow is connected to form a second branch, and the first branch and the second branch are arranged alternately along the up and down direction of the housing, so that the first heat exchange on the first branch The tubes and the second heat exchange tubes on the second branch are alternately distributed in the heat exchange range of the cross flow heat exchanger, so that the first branch and the second branch can Covering the entire windward area of the cross-flow heat exchanger for heat exchange; in addition, when the cross-flow heat exchanger is applied to a parallel heat pump system, the refrigerant of one of the independent systems flows through the first branch, and the other The refrigerant of one independent system flows through the second branch, and when one of the independent systems is out of operation, the refrigerant of the other independent system flows through the second branch and uses the energy of the entire cross-flow heat exchanger The windward area is used for heat exchange, so as to ensure the heat exchange area of the parallel heat pump system when only one system is running, so as to improve the heat exchange efficiency of the parallel heat pump system when only one system is running, thereby ensuring the heat exchange capacity of the heat exchanger and Avoid high voltage problems. The embodiment of the present invention also provides a multi-stage heating heat pump system.

Description of drawings

Fig. 1 is the front view of a kind of cross-flow heat exchanger in the embodiment of the present invention;

Fig. 2 is the right side view of a kind of cross-flow heat exchanger in the embodiment of the present invention;

Fig. 3 is a branch schematic diagram of a cross-flow heat exchanger in an embodiment of the present invention;

Fig. 4 is a schematic structural diagram of a multi-stage heating heat pump system in an embodiment of the present invention;

Among them, 10, heat exchange elbow; 11, first heat exchange elbow, 12, second heat exchange elbow; 101, first branch; 102, second branch; 21, first air intake pipe; 211, 22, the first liquid outlet pipe; 221, the first liquid outlet pipe; 31, the second air inlet pipe; 311, the second air inlet pipe; 32, the second liquid outlet pipe; 321, 4. The first system; 41. The first compressor; 42. The first evaporator; 43. The first throttling device; 5. The second system; 51. The second compressor; 52. The second evaporator; 53, the second throttling device; 6, the third system; 61, the third compressor; 62, the third evaporator; 63, the third throttling device; 7, the fourth system; 71, the first Four compressors; 72, the fourth evaporator; 73, the fourth throttling device; 81, the first cross-flow heat exchanger; 82, the second cross-flow heat exchanger; 9, fins.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

Referring to Figures 1-3, a cross-flow heat exchanger according to a preferred embodiment of the present invention includes a shell, several heat exchange tubes and several heat exchange elbows 1, the heat exchange tubes are arranged in the shell, and the The heat exchange elbow 1 is arranged on the outer wall of the housing; the heat exchange tube includes a first heat exchange tube and a second heat exchange tube, and the heat exchange elbow 1 includes a first heat exchange elbow 11 and a second heat exchange tube. The second heat exchange elbow 12, the first heat exchange tube communicates with the first heat exchange elbow 11 and forms a first branch, the second heat exchange tube and the second heat exchange elbow 12 communicate and form a second branch, and the first branch and the second branch are arranged alternately along the up-down direction of the housing.

In the embodiment of the present invention, the first branch path 101 and the second branch path 102 are arranged alternately along the up and down direction of the casing, so that the first heat exchange on the first branch path 101 Tubes and the second heat exchange tubes on the second branch 102 are alternately distributed in the heat exchange range of the cross flow heat exchanger, so that the first branch 101, the second branch The path 102 can cover the entire windward area of the cross-flow heat exchanger for heat exchange; in addition, when the cross-flow heat exchanger is applied to a parallel heat pump system, the refrigerant of one of the independent systems passes through the first branch path 101, the refrigerant of another independent system flows through the second branch path 102, and when one of the independent systems stops running, the refrigerant of the other independent system flows through the second branch path 102 and uses the entire The windward area of the cross-flow heat exchanger described above is used for heat exchange, so as to ensure the heat exchange area of the parallel heat pump system when only one system is running, so as to improve the heat exchange efficiency of the parallel heat pump system when only one system is running, and thus ensure the heat transfer efficiency of the parallel heat pump system. Heat transfer capacity of the heater and avoid high pressure problems.

In the embodiment of the present invention, it should be noted that the first heat exchange tube corresponds to the first heat exchange elbow 11 one by one, and the second heat exchange tube corresponds to the second heat exchange elbow 12 One to one correspondence.

Referring to Fig. 2 and Fig. 3, in the embodiment of the present invention, the first heat exchange elbow 11 and the second heat exchange elbow 12 are evenly distributed on the outer side wall of the housing, so as to be compatible with the The first heat exchange tubes communicated with the first heat exchange elbow 11 and the second heat exchange tubes communicated with the second heat exchange elbow 12 can be evenly distributed in the housing, thereby ensuring that the Both the first branch 101 and the second branch 102 can use the entire windward area of the cross-flow heat exchanger for heat exchange.

Referring to Fig. 1 and Fig. 2, in the embodiment of the present invention, it also includes a first air inlet pipe 21, a first liquid outlet pipe 22, a second air inlet pipe 31 and a second liquid outlet pipe 32; The inlet end communicates with the first air inlet pipe 21, the outlet end of the first shunt 101 communicates with the first liquid outlet pipe 22, and the inlet end of the second shunt 102 communicates with the second air inlet pipe. 31, the outlet port of the second branch 102 is connected with the second outlet pipe 32, so that the refrigerant can pass through the first inlet pipe 21 into the first branch 101 and flow from the second A liquid outlet pipe 22 flows out to facilitate refrigerant flow and heat exchange in the first sub-circuit 101; The second liquid outlet pipe 32 flows out, so as to facilitate the refrigerant to flow in the second sub-circuit 102 and perform heat exchange.

In the embodiment of the present invention, the working principle of the cross-flow heat exchanger is: the cross-flow heat exchanger is suitable for parallel heat pump dual systems, and the high-temperature refrigerant gas of one system enters through the first intake pipe 21 Flow into the first branch 101 for heat exchange and become refrigerant liquid, and the refrigerant liquid flows out from the first liquid outlet pipe 22; the high-temperature refrigerant gas of another system enters through the second inlet pipe 31 Flow into the second branch 102 for heat exchange and become refrigerant liquid, and the refrigerant liquid flows out from the second liquid outlet pipe 32; when only one system in the parallel heat pump dual system is running, the refrigerant is still The refrigerant can flow in the first sub-circuit 101 or the second sub-circuit 102, and the refrigerant can cover the entire windward area of the cross-flow heat exchanger for heat exchange. Therefore, compared with the prior art parallel heat pump system in which the two system branches are designed to flow up and down, the embodiment of the present invention improves the heat exchange efficiency of the parallel heat pump system when only one system is running, ensuring the condensation capacity of the heat exchanger And avoid high voltage problems.

Referring to Fig. 1 and Fig. 2, in the embodiment of the present invention, the first air intake pipe 21 is provided with a first air intake thin pipe 211 and a number of first air outlet thin pipes for introducing refrigerant gas. The air inlet pipe 21 communicates with the first air inlet thin pipe 211, and the first air inlet pipe 21 communicates with the inlet end of the first branch 101 through several first air outlet thin pipes; the first liquid outlet The tube 22 is provided with a first thin liquid outlet tube 221 for refrigerant liquid to flow out and several first liquid inlet thin tubes, the first liquid outlet pipe 22 communicates with the first liquid outlet thin tube 221, and the first A liquid outlet pipe 22 communicates with the outlet end of the first branch path 101 through several first thin liquid inlet pipes.

Referring to Fig. 1 and Fig. 2, in the embodiment of the present invention, the second air intake pipe 31 is provided with a second air intake thin pipe 311 for introducing refrigerant gas and several second air outlet thin pipes, the second The air inlet pipe 31 communicates with the second air inlet thin pipe 311, and the second air inlet pipe 31 communicates with the inlet end of the second shunt 102 through several second air outlet thin pipes; the second liquid outlet The tube 32 is provided with a second liquid outlet thin tube and several second liquid inlet thin tubes for refrigerant liquid to flow out, the second liquid outlet pipe 32 communicates with the second liquid outlet thin tube 321, and the second The liquid outlet pipe 32 communicates with the outlet end of the second branch path 102 through several second thin liquid inlet pipes.

Referring to Fig. 1 and Fig. 2, in the embodiment of the present invention, several heat exchanging elbows 1 are arranged obliquely on the housing, and the first heat exchanging elbow 11 and the second heat exchanging elbow 12 is inclined, so that the first heat exchange tube connected to the first heat exchange elbow 11 and the second heat exchange tube communicated with the second heat exchange elbow 12 make full use of the shell The heat exchange space in the body, so that the wind entering the air inlet of the cross-flow heat exchanger can fully exchange heat with the refrigerant in the first heat exchange tube and the refrigerant in the second heat exchange tube.

Referring to Figure 1 and Figure 2, in the embodiment of the present invention, several heat exchange tubes are arranged in parallel, and the first heat exchange tube and the second heat exchange tube are arranged in parallel, so that the cross flow The wind entering from the air inlet of the heat exchanger performs sufficient heat exchange with the refrigerant in the first heat exchange tube and the refrigerant in the second heat exchange tube.

Referring to Fig. 1 to Fig. 3, in the embodiment of the present invention, fins 9 are also included, the fins 9 are arranged in the housing, and the fins 9 are connected with the outer side walls of the heat exchange tubes, so as to facilitate The heat exchange efficiency of the heat exchange tube is improved, thereby enhancing the heat exchange effect of the cross-flow heat exchanger.

In order to solve the same technical problem, the implementation of the present invention also provides a multi-stage heating heat pump system, including the first system 4, the second system 5, the third system 6, the fourth system 7, and the first cross-flow heat exchanger 81 And the second cross-flow heat exchanger 82, the first cross-flow heat exchanger 81 and the second cross-flow heat exchanger 82 are the above-mentioned cross-flow heat exchangers;

The first system 4 includes a first compressor 41 , a first throttling device 43 , and a first evaporator 42 , the outlet end of the first compressor 41 is connected to the first cross-flow heat exchanger 81 The inlet pipe 21 communicates, the first outlet pipe 22 of the first cross-flow heat exchanger 81 communicates with the first port of the first throttling device 43 , and the second port of the first throttling device 43 communicates with the first port of the first throttling device 43 The first port of the first evaporator 42 is communicated, and the second port of the first evaporator 42 is communicated with the inlet end of the first compressor 41;

The second system 5 includes a second compressor 51, a second throttling device 53, and a second evaporator 52, and the outlet end of the second compressor 51 is connected to the first The inlet pipe 21 communicates, the first outlet pipe 22 of the second cross-flow heat exchanger 82 communicates with the first port of the second throttling device 53 , and the second port of the second throttling device 53 communicates with the The first port of the second evaporator 52 is communicated, and the second port of the second evaporator 52 is communicated with the inlet port of the second compressor 51;

The third system 6 includes a third compressor 61 , a third throttling device 63 , and a third evaporator 62 , and the outlet end of the third compressor 61 is connected to the second The inlet pipe 31 communicates, the second liquid outlet pipe 32 of the first cross-flow heat exchanger 81 communicates with the first port of the third throttling device 63 , and the second port of the third throttling device 63 communicates with the The first port of the third evaporator 62 is communicated, and the second port of the third evaporator 62 is communicated with the inlet end of the third compressor 61;

The fourth system 7 includes a fourth compressor 71, a fourth throttling device 73, and a fourth evaporator 72. The outlet end of the fourth compressor 71 is connected to the second The inlet pipe 31 communicates, the second liquid outlet pipe 32 of the second cross-flow heat exchanger 82 communicates with the first port of the fourth throttling device 73 , and the second port of the fourth throttling device 73 communicates with the The first port of the fourth evaporator 72 is communicated with, and the second port of the fourth evaporator 72 is communicated with the inlet end of the fourth compressor 71 .

Referring to Fig. 3, in the embodiment of the present invention, the first cross-flow heat exchanger 81 and the second cross-flow heat exchanger 82 are arranged at the air outlet, and the first cross-flow heat exchanger 81 and the The second cross-flow heat exchanger 82 is arranged in parallel and against each other. Since the first cross-flow heat exchanger 81 and the second cross-flow heat exchanger 82 are arranged in parallel at the air outlet, the wind is directly parallel. Heat exchange is performed through the heat exchange surfaces of the first cross-flow heat exchanger 81 and the second cross-flow heat exchanger 82 , thereby improving the heat exchange efficiency of the multi-stage heating heat pump system.

In the embodiment of the present invention, it should be noted that the multi-stage heating heat pump system is mainly applied to grain dryers. The grain dryer uses two refrigerants, R410A and R134A, which can meet the requirement that the dryer can maintain a high energy efficiency ratio under low temperature conditions and high temperature conditions; the first throttling device 43 and the second throttling device 53 . The third throttling device 63 and the fourth throttling device 73 are thermal expansion valves or electronic expansion valves.

In the embodiment of the present invention, the working principle of the multi-stage heating heat pump system is:

When the first system 4 and the third system 6 use the same refrigerant, or the second system 5 and the fourth system 7 use the same refrigerant, the unit of the multi-stage heating heat pump system When just started, the multi-stage heating heat pump system can start the first system 4 and the second system 5, or the third system 6 and the fourth system 7 to work to provide a Dry drying heat. At this time, since the first cross-flow heat exchanger 81 and the second cross-flow heat exchanger 82 are arranged in parallel at the air outlet, the wind directly passes through the first cross-flow heat exchange in parallel. Heat exchange between the heat exchange surface of the heat exchanger 81 and the second cross-flow heat exchanger 82, thereby improving the heat exchange efficiency of the multi-stage heating heat pump system;

When the first system 4 and the third system 6 use different refrigerants, or the second system 5 and the fourth system 7, when the unit of the multi-stage heating heat pump system is just started, the The multi-stage heating heat pump system can start the first system 4 and the third system 6, or the second system 5 and the fourth system 7 to work to provide drying heat for grain drying, At this time, since the multi-stage heating heat pump system only needs to use the first cross-flow heat exchanger 81 or the second cross-flow heat exchanger 82 for internal heat exchange, it can meet the required drying heat requirements. Therefore, the heat exchange efficiency of the multi-stage heating heat pump system is improved.

Compared with the prior art, the beneficial effect of the embodiments of the present invention is that the embodiments of the present invention provide a cross-flow heat exchanger, including a shell, several heat exchange tubes and several heat exchange elbows, the heat exchange tubes It is arranged in the shell, and the heat exchange elbow is set on the outer wall of the shell; the heat exchange tube includes a first heat exchange tube and a second heat exchange tube, and the heat exchange elbow 10 includes The first heat exchange elbow 11 and the second heat exchange elbow 12, the first heat exchange tube communicates with the first heat exchange elbow 11 and forms a first branch 101, and the second heat exchange tube communicates with the first heat exchange elbow 11 and forms a first branch 101. The second heat exchange elbow 12 is connected to form a second branch 102, and the first branch 101 and the second branch 102 are arranged alternately along the up and down direction of the housing, so that the first The first heat exchange tubes on the branch 101 and the second heat exchange tubes on the second branch 102 are alternately distributed in the heat exchange range of the cross flow heat exchanger, so that the first Both the first branch 101 and the second branch 102 can cover the entire windward area of the cross-flow heat exchanger for heat exchange; in addition, when the cross-flow heat exchanger is applied to a parallel heat pump system, one of the independent The refrigerant of the system flows through the first branch 101, the refrigerant of the other independent system flows through the second branch 102, and when one of the independent systems stops running, the refrigerant of the other independent system flows through the The second branch 102 flows and covers the entire windward area of the cross-flow heat exchanger for heat exchange, so as to ensure the heat exchange area of the parallel heat pump system when only one system is running, so as to improve the parallel heat pump system when only one system is running. The high heat exchange efficiency ensures the heat exchange capacity of the heat exchanger and avoids high pressure problems. At the same time, the embodiment of the present invention also provides a multi-stage heating heat pump system, and the heat exchange efficiency of the multi-stage heating heat pump system is higher.

The above description is a preferred embodiment of the present invention, and it should be pointed out that for those skilled in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications are also considered Be the protection scope of the present invention.

Claims (10)

1. a kind of cross flow heat exchanger, it is characterised in that including housing, some heat exchanger tubes and some heat exchange elbows, the heat exchange Pipe is arranged in the housing, and the heat exchange elbow is arranged on the lateral wall of the housing；

The heat exchanger tube includes the first heat exchanger tube and the second heat exchanger tube, and the heat exchange elbow includes the first heat exchange elbow and second and changed Hot bending head, first heat exchanger tube connect with the described first heat exchange elbow and form the first branch, second heat exchanger tube and institute The second heat exchange elbow is stated to connect and form the second branch, and first branch and second branch along the housing up and down Direction is arranged alternately.

2. cross flow heat exchanger as claimed in claim 1, it is characterised in that the first heat exchange elbow and second heat exchange Elbow is evenly distributed on the lateral wall of the housing.

3. cross flow heat exchanger as claimed in claim 1 or 2, it is characterised in that also go out liquid including the first air inlet pipe, first Pipe, the second air inlet pipe and the second drain pipe；

The entrance point of first branch connects with first air inlet pipe, and the port of export of first branch goes out with described first Liquid pipe connects, and the entrance point of second branch connects with second air inlet pipe, the port of export of second branch with it is described Second drain pipe connects.

4. cross flow heat exchanger as claimed in claim 3, it is characterised in that first air inlet pipe, which is provided with, to be used to be passed through system The the first air inlet tubule and some first outlet tubules of refrigerant gas, first air inlet pipe connect with the first air inlet tubule Logical, first air inlet pipe is connected by some first outlet tubules with the entrance point of first branch；

First drain pipe is provided with goes out liquid tubule and some first feed liquor tubules, institute for the first of refrigerant liquid outflow State the first drain pipe and go out liquid tubule with described first and connect, first drain pipe passes through some first feed liquor tubules and institute State the port of export connection of the first branch.

5. cross flow heat exchanger as claimed in claim 3, it is characterised in that second air inlet pipe, which is provided with, to be used to be passed through system The the second air inlet tubule and some second outlet tubules of refrigerant gas, second air inlet pipe connect with the second air inlet tubule Logical, second air inlet pipe is connected by some second outlet tubules with the entrance point of second branch；

Second drain pipe is provided with goes out liquid tubule and some second feed liquor tubules, institute for the second of refrigerant liquid outflow State the second drain pipe and go out liquid tubule with described second and connect, second drain pipe passes through some second feed liquor tubules and institute State the port of export connection of the second branch.

6. cross flow heat exchanger as claimed in claim 1 or 2, it is characterised in that some heat exchange elbows are inclined at On the lateral wall of the housing, and the first heat exchange elbow is obliquely installed with the described second heat exchange elbow.

7. cross flow heat exchanger as claimed in claim 1, it is characterised in that it is be arranged in parallel between some heat exchanger tubes, and First heat exchanger tube be arranged in parallel with second heat exchanger tube.

8. cross flow heat exchanger as claimed in claim 1, it is characterised in that also including fin, the fin is arranged on described In housing, the fin is connected with the lateral wall of the heat exchanger tube.

9. a kind of Multi-stage heating heat pump, it is characterised in that including the first system, second system, the 3rd system, the 4th system System, the first cross flow heat exchanger and the second cross flow heat exchanger, first cross flow heat exchanger, second cross-current change Hot device is the cross flow heat exchanger as described in any one of claim 3~8；

The first system includes the first compressor, first throttle device, the first evaporator, the port of export of first compressor Connected with the first air inlet pipe of first cross flow heat exchanger, the first drain pipe of first cross flow heat exchanger with it is described The first port connection of first throttle device, the second port of the first throttle device and the first end of first evaporator Mouth connection, the second port of first evaporator connect with the entrance point of first compressor；

The second system includes the second compressor, second throttling device, the second evaporator, the port of export of second compressor Connected with the first air inlet pipe of second cross flow heat exchanger, the first drain pipe of second cross flow heat exchanger with it is described The first port connection of second throttling device, the second port of the second throttling device and the first end of second evaporator Mouth connection, the second port of second evaporator connect with the entrance point of second compressor；

3rd system includes the 3rd compressor, the 3rd throttling arrangement, the 3rd evaporator, the port of export of the 3rd compressor Connected with the second air inlet pipe of first cross flow heat exchanger, the second drain pipe of first cross flow heat exchanger with it is described The first port connection of 3rd throttling arrangement, the second port of the 3rd throttling arrangement and the first end of the 3rd evaporator Mouth connection, the second port of the 3rd evaporator connect with the entrance point of the 3rd compressor；

4th system includes the 4th compressor, the 4th throttling arrangement, the 4th evaporator, the port of export of the 4th compressor Connected with the second air inlet pipe of second cross flow heat exchanger, the second drain pipe of second cross flow heat exchanger with it is described The first port connection of 4th throttling arrangement, the second port of the 4th throttling arrangement and the first end of the 4th evaporator Mouth connection, the second port of the 4th evaporator connect with the entrance point of the 4th compressor.

10. Multi-stage heating heat pump as claimed in claim 9, it is characterised in that first cross flow heat exchanger and institute The second cross flow heat exchanger is stated to be arranged at air outlet, and first cross flow heat exchanger and second cross flow heat exchanger It is arranged in parallel and abuts.