JPS5941111B2 - rotary heat exchanger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary heat exchanger, and its purpose is to provide a fluid supply/drainage header for supplying and distributing heat source fluid to hollow blades of the rotary heat exchanger. By arranging the two outward paths so that their positions differ by 180 degrees with respect to the center of rotation, and by providing the two return paths so that their positions differ by 180 degrees with respect to the center of rotation and adjacent to the two outward paths, When using a fluid that undergoes a phase change, such as a refrigerant, as the internal fluid, it is important to maintain dynamic balance during rotation.

In recent years, as shown in Figure 1, the blades 1 of a blower are hollow blades, and by flowing a heat source fluid (e.g., water or refrigerant) 2 inside the blades, heat exchange is performed with a fluid (e.g., air) 3 outside the hollow blades. The rotary heat exchanger 4 is attracting attention.

In addition to having the functions of an air blower and a heat exchanger at the same time, this device also significantly improves the heat exchange capacity by rotating the heat transfer surface, so it is seen as a very promising means of improving the performance and downsizing of air conditioners. It is something that

Conventionally, typical configurations of rotary heat exchangers have been as shown in FIGS. 2 and 3.

In FIG. 2, both ends of the hollow blades 5 are supported by a supply header 7 and a discharge header 8 for a heat source side fluid (hereinafter referred to as internal fluid) 6 to form a multi-blade rotor.

The internal fluid 6 entering from the liquid feeding chamber 9 flows through the hollow rotating shaft 10 as shown by the solid arrow. Supply header 7, hollow vane 5. Discharge header8. The liquid flows through the hollow rotating shaft 11 and the drain chamber 12 in this order, and exchanges heat with the air that crosses the hollow blades 5 .

13 is an electric motor that rotates the multi-blade rotor, and 14 is an annular fin that connects the plurality of hollow blades 5 in the circumferential direction.

The disadvantages of this are that the liquid feeding chamber 9, the multi-blade rotor, the liquid drainage chamber 12
, and the electric motor 13 are arranged in series on the rotating shaft, the overall length in the axial direction becomes too long, which does not lead to miniaturization.

Furthermore, seals 15, 16, and 17 are required to prevent the internal fluid 6 from leaking into the air on both sides of the liquid feeding chamber 10 and the liquid draining chamber 12, resulting in an increase in cost and rotational torque.

As a countermeasure for shortening the total length in the conventional example shown in FIG. 2, there is a conventional example shown in FIG. 3.

This has a hollow rotary shaft 18 having a double pipe structure to form an outgoing path 18a and a returning path 18b for the internal fluid 6, and both ends of the hollow blade 5 are connected to a liquid supply/drain header 19 and a return header 2.
Supported at 0.

The internal fluid that has flowed into the hollow rotary shaft forward path 18a from the liquid feeding chamber 9 flows into the hollow blade 5 from the liquid supply/drainage header 19, and is then transferred to the return header 20, the hollow blade 5', and the supply/drainage header 19.
, and flows into the hollow rotary shaft return path 18b.

Thereafter, the liquid is discharged from the drain chamber 12. Above all,
Since the liquid feeding chamber 9 and the liquid draining chamber 12 are housed in one shaft sealing device 22 with the sealing device 21 in between, the overall length is shorter than that of the conventional example shown in FIG. 2, resulting in a smaller size.

However, the conventional example shown in FIG. 3 has the following drawbacks.

One is that since the structure of the hollow rotating shaft 18 is a double pipe type, the outer diameter 18D of the outer pipe becomes large in order to ensure a fluid passage cross-sectional area of the return path 18b.

This increases the diameter of the mechanical seal 23 used for shaft sealing between the drain chamber 12 and the external space, and the seal sliding surface 2
Since the diameter of the motor 4 becomes large, the output of the electric motor 13 must be made equal to the output of the electric motor 13.

Furthermore, the diameter of the bearing portion 25 also increases, leading to an increase in cost.

Second, since it is a double pipe system, high-precision machining is required to satisfy the allowable mounting dimensions of the shaft portion to which the seal device 21 and mechanical seal 23 are attached, which increases manufacturing costs. It became.

As a measure to eliminate the drawbacks of the conventional examples shown in FIGS. 2 and 3, a rotary heat exchanger shown in FIG. 4 has already been considered and is known.

The configuration of FIG. 4 will be explained below. The major difference from FIG. 3 is that a hollow rotary shaft 29 whose interior is divided into two by a partition plate 26 and has an outward passage 27 and an incoming passage 28 for the internal fluid is connected to the liquid supply/drain header 19 of the multi-blade rotor. be.

The rest is basically composed of the same parts as in Fig. 3.

Further, 30 is a blower casing housing a multi-blade rotor, and a shaft sealing device 22 is attached to one end and a bearing portion 31 is attached to the other end.

The operation during operation is as follows.

The internal fluid 6 that has flowed into the liquid feeding chamber 21 enters the outgoing path 27 of the hollow rotating shaft 29 and passes through the outgoing path outlet 27a to the liquid supply/drainage header 19.
flows into.

Thereafter, the flow is divided into a suitable number of hollow blades 5 and flows into the return header 20j at the opposite end.

Thereafter, the liquid is guided by the remaining hollow blades 5' and flows into the liquid supply/drainage header 19, and then reaches the return path outlet 28b from the return passage port 28a of the hollow rotation shaft 29, and is discharged from the liquid drainage chamber 12.

As described above, in the conventional example shown in FIG.
3, the outer diameter of the hollow rotating shaft 29 does not increase, and the drawbacks of the conventional example shown in FIG. 3 are solved.

However, since the hollow rotating shaft 29 is divided into two parts, the liquid supply/drainage header 19 is subject to structural restrictions.
It had the following drawbacks.

Conventionally, configurations of the supply/discharge header 19 as shown in FIGS. 5 and 6 have been proposed and known (FIG. 5 is a sectional view taken along line A-A in FIG. 4, and FIG. 6 is a cross-sectional view taken along line A-A in FIG. (B-B sectional view in the figure).

Hereinafter, to explain the flow of the internal fluid, the internal fluid that entered the outward path 32 in the liquid supply/drain header 19 from the hollow rotary shaft outward path outlet 27a flows through the hollow blades 5-1, 5-2, 5-13,
5-14 and reaches the return header 20.

Here, the hollow blades 5-1 and 5-2 communicate with the relay path 33, and the hollow blades 5-13 and 5-14 communicate with the relay path 38.

In this way, once the internal fluid has exited the hollow rotating shaft 29 and flows into the hollow blade 5 through the supply/drain header 1 outgoing path 32'1, it is branched symmetrically when viewed from the drawing surface of Drawing 5. ,
After that, to the left are relay routes 33, 34, 35, as shown by solid arrows.
36, 37 and hollow blades 5-1, 5-2 to 5-11, 5-
12 alternately to the return path 43 in the supply/drainage header, and on the left, as indicated by the dotted arrow, there are relay paths 38, 39, 40° 4L.
42 and hollow blades 5-13, 5-14 to 5-23.5-2
4 alternately to the return path 43, and finally the symmetrical flows merge in the return path inside the liquid supply/drain header and flow out from the return path 28a provided in the hollow rotation shaft 29.

If a fluid that undergoes a phase change, such as a refrigerant, is used as the internal fluid of this rotary heat exchanger and used as a condenser or evaporator of a refrigeration system, the following disadvantages occur.

For example, when the conventional system shown in FIGS. 4, 5 and 6 is adopted as a condenser for a refrigeration system, there are three states of refrigerant in the condenser: superheated gas, saturated region, and supercooled liquid.

That is, among the hollow blades shown in FIG. 5, 5-1, 5-2,
5-13, 5-14, etc., a part or all of the hollow blades near the outgoing path 32 are occupied by superheated gas having a small specific weight.

Also, hollow blades 5-11゜5-12, 5-23, 5
A part or all of the hollow blades near the return path 43, such as -24, are occupied by supercooled refrigerant liquid having a large specific weight.

Incidentally, the ratio of the specific weight of R-12 saturated liquid to saturated gas is about 50:1.

In this way, if internal fluids with significantly different specific weights are present at substantially symmetrical positions with respect to the center of rotation, the center of gravity will shift during rotation, making it impossible to maintain dynamic balance.

This causes eccentricity and vibration of the hollow rotating shaft 29, and the shaft sealing device 2
2 and bearing parts 25 and 31 are significantly reduced.

In the worst case, even the rotary heat exchanger may be destroyed.

The present invention eliminates all the drawbacks of the conventional examples shown in FIGS. 2, 3, 4, 5, and 6.

Specifically, this goal can be achieved through the improvements shown in Figures 4.5 and 6.

FIG. 7 shows a liquid supply/drainage header 44 showing one embodiment of the present invention.

This consists of two outbound trips 45, 46 and two inbound trips 47.4.
8, and the two outgoing paths 4546 are relative to the center of rotation,
The two return paths 47, 48 have positions different by 180 degrees with respect to the center of rotation, and are located adjacent to the two outward paths 45, 46.

FIG. 8 shows a return header 49, which is structurally the same as the conventional one.

FIG. 9 shows a hollow rotary shaft 50 connected to the liquid supply/drainage header 44, whose interior is equally divided into four parts by a cross-shaped partition plate 51.

And internal fluid outward routes 52, 53 and return routes 54, 55
are arranged alternately, and the outgoing path 5253 is connected to the liquid feeding chamber 9 (fourth
The outgoing ports 52a and 53a are opened to the outgoing ports 52a and 53a (see figure), and the outgoing ports 52b and 53b are opened corresponding to the outgoing ports 45 and 46 in the liquid supply/drainage header 44, and the incoming ports 54 and 5
5 is a return path outlet 54b t 55b that opens into the drain chamber 12
Also, return passages 54a and 55a are opened corresponding to the return passages 47 and 48 in the liquid supply/drainage header 44.

Everything else is the same as in FIG. Changes in the state of the refrigerant when the present invention having the above configuration is used, for example, as a condenser of a refrigeration system will be explained with reference to FIGS. 7 and 8.

The high-temperature superheated refrigerant gas that has flowed from the compressor into the outgoing path 45 of the liquid supply/drainage header 44 via the outgoing path 52 of the hollow rotary shaft 50 flows into the hollow blades 5-1 and 5-2 as indicated by solid arrows.

Then, it reaches the return route 47 through the relay routes 56, 57, 58, 59, 60 and the hollow blades 5-3, 5-4 to 5-11.5-12 alternately.

During this period, the refrigerant exists in three states, superheated gas, two-phase region, and supercooled liquid, in a certain ratio.

On the other hand, the high-temperature superheated refrigerant gas flowing into the outgoing path 46 of the hollow rotating shaft 50 flows through the hollow blades 5-1:3, 5-14, as shown by the dotted arrows.
-5-23, 5-24 and relay paths 61, 62, 63,
64 and 65 alternately to reach the return route 48.

Meanwhile, the refrigerant is present in the same proportions as the above-mentioned proportions: superheated gas, two-phase region and subcooled liquid.

That is, as shown in a simplified manner in FIG. 10, the states (for example, temperature, specific weight, etc.) of the refrigerant at arbitrary points E and F, whose positions differ by 180 degrees with respect to the center of rotation, are the same.

This phenomenon is maintained even if the ratio changes due to some reason, for example, during driving.

Therefore, during rotation, the centrifugal forces at two points that are 180 degrees apart are balanced, and no movement of the center of gravity occurs.

As described above, the rotary heat exchanger of the present invention includes a hollow rotating shaft 50 having internal fluid outgoing paths 52, 53 and incoming fluid paths 54, 55, and a multi-blade rotor formed by hollow blades 5. , two outbound trips 45,46 and two return trips 47,48
and are connected via a liquid supply and drainage header 44 having a plurality of relay paths, and the two outgoing paths 45 and 46 in the liquid supply and drainage header 44 are arranged so that their positions differ by 180 degrees with respect to the center of rotation, The positions of the two return paths 47 and 48 differ by 180 degrees with respect to the center of rotation, and the two outward paths 45
, 46, so even if a fluid that undergoes a phase change such as a refrigerant is used as the internal fluid, the state of the refrigerant at any two points whose positions differ by 180 degrees with respect to the center of rotation can be determined. are the same, therefore, during rotation, the centrifugal forces at the two arbitrary points are balanced and a good dynamic balance is maintained.

As a result, the eccentricity and vibration of the hollow rotating shaft 50 are eliminated, and the durability of the shaft sealing device 22 and the bearings 25 and 31 can be improved.

In addition, the head loss Δh of the fluid when the inside of the hollow rotating shaft 50 is divided into n chambers is calculated by setting the fluid friction coefficient to λ, the axial length of the hollow rotating shaft 50 to l, the flow rate to Vo, and the gravitational acceleration to g. Or, the total flow path cross-sectional area of the return path, A(), is the inner diameter of the hollow rotating shaft d, regardless of the number of divisions n.Here, the thickness of the partition plate 51 required for division has a slight influence on Ao. Therefore, it is ignored.

The flow velocity V of the fluid flowing through the flow path is It is expressed as

Head loss Δh is a well-known formula It is expressed as

Here, d is the flow passage hydraulic diameter of one chamber divided into n chambers, the flow passage cross-sectional area An of one chamber, and the flow passage wetting length l
If n, then substituting equation 1.2,4 into equation 3 yields the following.

From Equation 5, as the internal division number n in the hollow rotating shaft 50 increases, the water head loss Δh increases.

Therefore, in order to reduce the water head loss Δh, it is better to have a smaller number of divisions in the hollow rotating shaft 50.

The smallest number of divisions n is n -2, but this is nothing but the conventional example shown in Figs. When used as a condenser or evaporator, it has the disadvantage that the multi-blade rotor cannot be dynamically balanced during rotation.

Therefore, the number of divisions n to eliminate the drawbacks of the conventional example is n > 2, and at the same time, n = 4 is the best from the viewpoint of minimizing the above-mentioned water head loss Δh. It is better to divide it into rooms.

Further, the structure of the hollow rotating shaft 50 is such that the interior is divided into four chambers by a cross-shaped partition plate 51, and an outgoing path 52 for internal fluid.
．． 53 and return paths 54 and 55, the mechanical strength ( It has various excellent effects, such as significantly improving twisting, deflection, etc.).

In addition, it goes without saying that the drawbacks of the conventional examples shown in FIGS. 2 and 3 are also eliminated.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway perspective view of a conventional rotary heat exchanger, Fig. 2 is an explanatory diagram of a conventional rotary heat exchanger, Fig. 3 is a sectional view of the same side, and Fig. 4 is a perspective view of a conventional rotary heat exchanger. FIG. 5 is an explanatory diagram of a conventional rotary heat exchanger, FIG. 5 is an explanatory diagram of a supply/discharge header, FIG. 6 is an explanatory diagram of a return header, and FIG. 7 is an explanatory diagram of a rotary heat exchanger in an embodiment of the present invention. Supply/drainage liquid to be used...Explanatory diagram of the ladder, Figure 8 is an explanatory diagram of the same return header, Figure 9 a, b, c,
d is a perspective view, a side view, a sectional view, and a sectional view of the hollow rotating shaft, respectively, and FIG. 10 is an explanatory view showing the action of the hollow rotating shaft. 5...Hollow blade, 44...Liquid supply/drain header, 45.46...Outward path, 47,48...
...Return trip, 50...Hollow rotating shaft, 51...
...Partition plate, 52, 53... Outbound, 52a
, 53a... Outbound entrance, 52b. 53b... Outward exit, 54, 55...
・Return route, 54a, 55a-”・Return route entrance, 54b,
55b-・・・Return exit.

Claims (1)

[Claims] 1. Outward paths 52, 53 and inward paths 54, 55 for fluid inside.
A hollow rotating shaft 50 having a rotor and a multi-blade rotor formed of hollow blades 5 are connected to a liquid supply/drainage header having two outward paths 45 and 46, two return paths 47 and 4B, and a plurality of relay paths. 44, and the water supply/drainage header 4
The two outgoing paths 45 and 46 in 4 are arranged so that their positions differ by 180 degrees with respect to the center of rotation, and the two incoming paths 47 and 4
A rotary heat exchanger characterized in that the positions of the heat exchangers 8 and 8 are different from each other by 180° with respect to the center of rotation and are provided adjacent to the two outgoing paths 45 and 46. 2 The hollow rotating shaft 50 has a cross-shaped partition plate 5 inside.
1 is divided into four chambers, each chamber is provided with a fluid outlet and an inlet, respectively, and two fluid outgoing paths 52 and 53 and two inward paths 54 and 55 are formed, and the two outgoing paths 52 and 53 are 2. The rotary heat exchanger according to claim 1, wherein the rotary heat exchanger is provided at a position different from the center of rotation by 1800 degrees.