JP3291800B2 - Method for forming cooling channel of constrictor disk - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming a cooling passage having a high cooling efficiency in a restrictor disk constituting a restrictor of a restrictor type arc heater.

[0002]

2. Description of the Related Art Conventionally, arc heating in which a high temperature plasma stream is blown against a test piece arranged at a required position in a wind tunnel to perform a heat test (heat resistance test, erosion test, etc.) on the test piece. Although a wind tunnel test apparatus is known, in recent years, a heat test having a large heat capacity has been desired. Therefore, the arc heating wind tunnel test apparatus tends to be large-sized, and a heating apparatus which generates a plasma airflow having a large heat capacity is used. A constrictor-type arc heater has been used as an apparatus.

FIG. 7 and FIG. 8 show an example of the above-mentioned constrictor type arc heater. This type of constrictor type arc heater 18 basically has a discharge path 3 formed between a cathode 1 and an anode 2. A working gas 5 is supplied through a working gas introduction flow path 4, and the working gas 5 is ejected from a nozzle 7 as a high-temperature plasma gas flow 5 ′ by an arc discharge 6 generated between the cathode 1 and the anode 2. However, in order to further increase the heat capacity, a constrictor capable of maintaining the periphery of the discharge path 3 at a low temperature by the cooling water 10 introduced into the cooling flow path 17 through the water supply path 8 and the drainage path 9. 11
Is interposed between the cathode 1 and the anode 2 so that a large separation distance between the cathode 1 and the anode 2 is set so that a large current and a large voltage can be applied.

That is, in order to apply a large current and a large voltage, it is necessary to increase the distance between the cathode 1 and the anode 2. However, simply increasing the distance between the cathode 1 and the anode 2 causes arc discharge. 6 cannot be stabilized. However, since the electric conductivity of the gas becomes higher as the temperature becomes higher, if the surroundings of the discharge path 3 are cooled by surrounding the discharge path 3 with the constrictor 11, the arc discharge 6 (current) becomes a discharge path having a lower temperature. Discharge path 3 avoiding the surrounding wall 3
Flow around the axis of the
In the vicinity of the axis of the discharge path 3 where the flow has flowed, the temperature rises due to Joule heat and the electrical conductivity increases, so that the arc discharge 6 easily flows to the axis of the discharge path 3 and the arc discharge 6 is stabilized. Will be planned.

The constrictor 11 needs to maintain an appropriate potential gradient in the axial direction of the discharge path 3 (the left-right direction in FIG. 7). A plurality of sheets are continuously combined in the axial direction while being insulated from each other by the interposition of the insulating member 13. The rear position of the cathode 1 and the front position of the anode 2 in the ejection direction of the plasma gas flow 5 ′. A relatively long connecting bolt 1 extending in the axial direction of the constrictor 11
By fastening at 6, the constrictor disks 12 and the insulating members 13 combined as the constrictor 11 are sandwiched and integrally held.

In such a conventional constrictor type arc heater, the cooling by the cooling water 10 is not only for the purpose of stabilizing the arc discharge 6 but also for protecting the constrictor 11 from the heat of the high-temperature plasma gas flow 5 '. However, the cooling efficiency is not sufficient if the cooling water 10 is merely cooled by flowing the cooling water 10 through the annular cooling flow path 17 formed around the discharge path 3 as described above. However, since the entire constrictor disk 12 constituting the constrictor 11 could not be sufficiently cooled, the constrictor disk 12 deteriorated in a short-time experiment and needed to be replaced frequently. There was a problem that becomes.

Therefore, as shown in FIG. 9, the inventors of the present invention configured the restrictor disk 12 as a set of divided pieces 12a and 12b, which were divided into an inner peripheral portion and an outer peripheral portion at an intermediate portion in the radial direction. And the inner peripheral side divided piece 12
A cooling flow path 17 'having a ring-shaped fin 12c is formed on the outer peripheral portion of a, and is fitted inside the outer peripheral side divided piece 12b, and the divided pieces 12a and 12b are integrated by brazing. It was considered that the heat exchange area between the cooling water 10 and the constrictor disk 12 was increased to improve the cooling efficiency.

[0008]

However, in the above-described conventional method, since brazing portions are required on both front and rear surfaces of the constrictor disc to secure the sealing property of the cooling flow path, the constrictor disc is not required. After completing the brazing work on one side, the constrictor disk must be turned over and the brazing work on the other side must be performed, which requires two brazing operations on one constrictor disk was there. That is, since a plurality of the above-mentioned constrictor disks are required to constitute the constrictor and are consumables, it takes a great deal of time to perform two brazing operations on one constrictor disk. Will be.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a method of forming a cooling passage of a restrictor disk, which can easily form a cooling passage having a higher cooling efficiency than conventional ones.

[0010]

According to the present invention, an annular recess is provided on one side of a constrictor disk of a constrictor type arc heater so as to surround a discharge path formed at a center portion. A water supply channel and a drainage channel are bored inside the constrictor disk so that cooling water can be introduced and discharged, and a hollow disk-shaped lid portion capable of closing an open surface of the annular concave portion and a protruding portion provided on one side surface of the lid portion. A fitting piece composed of fins that can be accommodated in the annular recess is fitted into a constrictor disc such that the fin projects into the annular recess, and the inner and outer peripheral portions of the lid of the fitting piece are The present invention relates to a method for forming a cooling passage of a constrictor disk, which comprises brazing the constrictor disk in a liquid-tight manner.

[0011]

Therefore, according to the present invention, the fitting piece is fitted into the annular recess formed on one side of the constrictor disc, and the inner and outer peripheral portions of the lid of the fitting piece are liquid-tight with respect to the constrictor disc. When the brazing is performed, the space surrounded by the annular concave portion and the lid of the fitting piece is formed as a cooling channel having fins. This can be performed by brazing the fitting piece on one side.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 6 show one embodiment of the present invention, and the portions denoted by the same reference numerals as those in FIGS. 7 and 8 represent the same components.

As shown in FIGS. 1 and 2, one side of the constrictor disk 12 (the right side in FIG. 1).
An annular concave portion 1 surrounds a discharge path 3 formed at the center.
A water supply channel 8 and a drainage channel 9 extending in the radial direction are formed in the constrictor disc 12 so that the cooling water 10 can be introduced into and discharged from the annular concave portion 19.

As shown in FIGS. 3 and 4, a hollow disk-shaped lid portion 21 capable of closing the open surface 20 (see FIG. 1) of the annular concave portion 19 is formed on one side surface of the lid portion 21. The fitting piece 23 including the fin 22 that can be accommodated in the annular recess 19 is manufactured.

Although the present invention is not limited by the shape of the fins 22 in the present embodiment, the shape of the fins 22 extends from the position closer to the inner periphery of the lid 21 in the axial direction. The L-shaped cross-section bent toward the radially outer circumference after being slightly extended has a shape as if it is turned 360 ° in the circumferential direction. A notch 24 extending in the radial direction for guiding the cooling water 10 without pressure loss is formed.

Next, as shown in FIGS. 5 and 6, the fitting piece 23 as described above is
And fitted into the annular recess 24 so that the notch 24 of the fin 22 faces the water supply passage 8 of the restrictor disc 12.
When the inner peripheral portion 21a and the outer peripheral portion 21b are brazed to the constrictor disk 12 in a liquid-tight manner (see brazing portions 25 and 26 in FIG. 5), the annular concave portion 19 is formed.
A space surrounded by the lid 21 of the fitting piece 23 is formed as a cooling channel 27 having the fin 22.

At this time, the open surface 20 of the annular recess 19 is
In the outer peripheral portion and the inner peripheral portion, a step portion for locking the inner peripheral portion 21a and the outer peripheral portion 21b of the lid portion 21 of the fitting piece 23 may be provided.

The cooling channel 27 having the fins 22
Since the fitting piece 23 can be brazed only on one side of the constrictor disk 12 to form the conical disk, the brazing operation for one constrictor disk 12 is completed in one process.

Therefore, according to the above-described embodiment, the provision of the fins 22 increases the heat exchange area between the cooling water 10 and the constrictor disk 12 side, thereby easily forming the cooling passage 27 with improved cooling efficiency. can do.

It should be noted that the method for forming a cooling passage of a constrictor disk according to the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention. It is.

[0022]

According to the method for forming a cooling passage of a restrictor disk according to the present invention described above, the fins are provided to increase the heat exchange area between the cooling water and the restrictor disk, thereby improving the cooling efficiency. The excellent effect that the cooling flow path which can be formed can be formed very easily in the constrainer disk can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a state in which an annular recess is formed in a constrictor disk according to an embodiment of the present invention.

FIG. 2 is a view in the direction of arrows II-II in FIG.

FIG. 3 is a longitudinal sectional view showing an example of a fitting piece according to one embodiment of the present invention.

FIG. 4 is a view in the direction of arrows IV-IV in FIG. 3;

FIG. 5 is a longitudinal sectional view showing a state in which a fitting piece is fitted into an annular concave portion and brazed in one embodiment of the present invention.

FIG. 6 is a view in the direction of arrows VI-VI in FIG. 5;

FIG. 7 is a longitudinal sectional view showing an example of a conventional constrictor type arc heater.

FIG. 8 is a cross-sectional view of the restrictor disc of FIG. 7;

FIG. 9 is a longitudinal sectional view showing an example of a conventional cooling channel forming method.

[Explanation of symbols]

 REFERENCE SIGNS LIST 3 discharge path 8 water supply path 9 drain path 10 cooling water 12 constrictor disk 18 constrictor-type arc heater 19 annular concave part 20 open surface 21 lid 21 a inner peripheral part 21 b outer peripheral part 22 fin 23 fitting piece 24 notch part 27 cooling flow Road

Continuation of the front page (56) References JP-A-60-208085 (JP, A) JP-A-4-240352 (JP, A) JP-T4-50000741 (JP, A) US Patent 3,695,959 (US, A) US Patent 3,953,705 (US, A) US Patent 4,535,225 (US, A) US Patent 3,891,828 (US, A) (58) Fields studied (Int. Cl. ⁷ , DB name) / 18 H05H 1/48

Claims (1)

(57) [Claims] An annular recess is provided on one side of a constrictor disk of a constrictor-type arc heater so as to surround a discharge path formed at a central portion, and cooling water is introduced into and out of the annular recess. A water supply channel and a drainage channel are bored inside the constrictor disc, and a hollow disk-shaped lid capable of closing the open surface of the annular recess and can be accommodated in the annular recess protruding from one side of the lid. A fitting piece composed of fins is fitted into a restrictor disc such that the fins protrude into an annular recess, and the inner peripheral portion and the outer peripheral portion of the lid of the fitting piece are liquid-tight to the constrictor disc. A method for forming a cooling channel of a constrictor disk, comprising brazing.