JPH05142104A - Arc heated wind channel test device - Google Patents

Abstract

PURPOSE:To obtain an arc heated wind channel test device which can exhaust gas positively without causing a plasma air flow to be overflown. CONSTITUTION:A title item 20 allows a high-temperature plasma stream 5 which is generated by an arc heater which is placed at an upstream side of a wind channel 1 to be exhausted with a diffuser having a convergence part 22 which is placed at the downstream side of the wind channel 1 and is spread in conical shape toward the arc heater side and then a sample 2 which is supported so that it can be moved in a flow direction (direction A marked by an arrow) of the plasma stream 5 within the wind channel 1 to be heated by the plasma stream flow 5. Then, a diffuser 21 is constituted so that it can be expanded and contracted in a flow direction of the plasma stream 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arc heating wind tunnel test apparatus.

[0002]

2. Description of the Related Art FIGS. 3 and 4 show an example of a conventional arc heating wind tunnel test apparatus, in which 1 is a wind tunnel and 2 is a support device 3 which is movable to a required position in the wind tunnel 1. 3 shows a test piece, and an arc heater 4 is arranged upstream of the wind tunnel 1 (on the left side in FIG. 3).
The high temperature plasma airflow 5 generated by the above is sprayed onto the sample 2 through the nozzle 6 having the diverging conical inner peripheral surface so that the heating test (heat resistance test, corrosion test, etc.) of the sample 2 can be performed. I am doing it.

Further, the downstream side of the wind tunnel 1 (right side in FIG. 3).
Is provided with a diffuser 8 having a converging portion 7 that spreads in a cone shape toward the nozzle 6 side. The plasma airflow 5 blown onto the sample 2 is converged by the converging portion 7 to the outside of the wind tunnel 1. It can be exhausted.

Further, the details of the arc heater 4 are as shown in FIG. 4, and between the pointed cathode 9 and the anodes 11 and 12 disposed on the downstream side of the cathode 9 via an insulating cover 10. Nitrogen 15 is supplied through the flow paths 13 and 14 and oxygen 17 is supplied through the flow path 16 into the gap of the above, and a voltage is applied between the cathode 9 and the anodes 11 and 12 to generate an arc. Let
A mixed gas of nitrogen 15 and oxygen 17 (a gas mixed in substantially the same manner as the atmosphere) can be ejected from a nozzle 6 as a high temperature plasma stream 5 by the arc discharge.

In FIG. 4, reference numeral 18 denotes a flow path for supplying the cooling water 19 into the anode 11.

In the conventional arc heating wind tunnel test apparatus as described above, as the means for changing the heating amount for the test piece 2, adjusting the electric power input to the arc heater 4 and the gas flow rate (nitrogen 15 and oxygen 17). It is conceivable to adjust the flow rate) or the distance between the support position of the sample 2 and the arc heater 4, and these means may be appropriately selected or used together to change the heating amount for the sample 2. Was there.

[0007]

However, in the conventional arc heating wind tunnel test apparatus as described above, since the diffuser 8 is fixedly installed in the wind tunnel 1, the specimen 2 is arced in order to increase the heating amount for the specimen 2. When brought close to the heater 4, the plasma airflow 5 may spread and overflow to the outside of the diffuser 8 depending on the size and shape of the sample 2, and the overflowing plasma airflow 5 exists in the wind tunnel 1. There is a risk of hitting the equipment such as No. 3 or the like and causing problems such as thermal deformation or seizure in the equipment.

The present invention has been made in view of the above situation, and an object of the present invention is to provide an arc heating wind tunnel test apparatus capable of reliably exhausting a plasma airflow without causing it to overflow.

[0009]

According to the present invention, a high temperature plasma stream generated by an arc heater disposed upstream of a wind tunnel is disposed downstream of the wind tunnel and directed toward the arc heater to form a cone shape. In the arc heating wind tunnel test apparatus, which is exhausted by a diffuser having a converging part that spreads in the air tunnel, and which heats a test piece supported in the wind tunnel so as to be movable in the flow direction of the plasma air stream, It is characterized in that it can be expanded and contracted in the flow direction of the air flow.

[0010]

Therefore, according to the present invention, by expanding and contracting the diffuser, the focusing portion of the diffuser can always be arranged immediately after the specimen even if the supporting position of the specimen with respect to the arc heater is changed. It is possible to reliably exhaust the gas without causing it to overflow.

[0011]

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

FIGS. 1 and 2 show an embodiment of the present invention, in which parts designated by the same reference numerals as those in FIGS. 3 and 4 represent the same parts.

An arc heating wind tunnel test apparatus 20 having substantially the same structure as the arc heating wind tunnel test apparatus of FIGS. 3 and 4 described above.
In, the diffuser 21 for exhausting the plasma airflow 5 is configured to be expandable and contractable in the flow direction of the plasma airflow 5 (the direction indicated by arrow A in FIGS. 1 and 2).

That is, a cylindrical fixed diffuser 21a is fixedly disposed on the downstream side of the wind tunnel 1 so as to penetrate the wind tunnel 1, and the arc heater 4 (FIG. 3) is provided at the upstream end of the fixed diffuser 21a. (See) the movable diffuser 21b having a converging portion 22 that spreads in a cone shape toward the side, is slidably inserted in the axial direction, and further extends in the axial direction opened at a required position of the fixed diffuser 21a. Long hole 23
A bearing in which a screw member 24 is attached to a required position on the outer peripheral surface of the movable diffuser 21b through a screw screw 24, which is screwed into a ball screw 25 extending in the axial direction, and one end of the ball screw 25 is fixed to the fixed diffuser 21a. The diffuser 21 is formed by pivotally connecting the ball screw 25 to the pulse motor 26 and connecting the other end of the ball screw 25 to the pulse motor 27 attached to the fixed diffuser 21a.

When the ball screw 25 is rotationally driven by the pulse motor 27, the movable diffuser 21b moves in the axial direction via the screw member 24 screwed to the ball screw 25, so that the arc heater 4 Specimen 2 for
It is possible to always arrange the converging part 22 of the diffuser 21 immediately after the specimen 2 even if the support position of the specimen 2 is changed, and the specimen 2 is placed close to the arc heater 4 in order to increase the heating amount for the specimen 2. In this case, even if the plasma airflow 5 spreads widely due to the size and shape of the sample 2, the movable diffuser 21b can be brought close to the sample 2 and the plasma airflow 5 can be taken in from the focusing part 22. Become.

When it is desired to support the test piece 2 apart from the arc heater 4 in order to reduce the amount of heat applied to the test piece 2, the movable diffuser 21b is pulled into the fixed diffuser 21a so that the diffuser 21 is located downstream. It should be shortened to.

Therefore, according to the above-described embodiment, by expanding and contracting the diffuser 21, the plasma airflow 5 can be surely exhausted without overflowing, so that thermal deformation or seizure of the equipment in the wind tunnel 1 can be prevented. Therefore, it is possible to extend the life of the arc heating wind tunnel test apparatus 20 and reduce the maintenance cost.

The arc heating wind tunnel test apparatus of the present invention is
The present invention is not limited to the above-described embodiment, and as the means for driving the diffuser to expand and contract, a rack and a pinion may be used in addition to the illustrated example, and a cylinder device may be used. Needless to say, various changes can be made without departing from the scope of the invention.

[0019]

According to the above-described arc heating wind tunnel test apparatus of the present invention, by expanding and contracting the diffuser, the plasma airflow can be reliably exhausted without overflowing, so that thermal deformation or burning of the equipment in the wind tunnel is achieved. It is possible to prevent sticking and the like, and therefore, it is possible to obtain excellent effects such as extending the life of the arc heating wind tunnel test apparatus and reducing the maintenance cost.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a view taken along line II-II in FIG.

FIG. 3 is a schematic view showing a conventional example.

4 is a cross-sectional view of the arc heater of FIG.

[Explanation of symbols]

 1 Wind Tunnel 2 Specimen 4 Arc Heater 5 Plasma Air Flow 20 Arc Heating Wind Tunnel Test Device 21 Diffuser 22 Focusing Part A Flow Direction of Plasma Air Flow 5

Claims (1)

[Claims] 1. A diffuser having a converging portion, which is arranged downstream of the wind tunnel and spreads in a cone shape toward the arc heater, to generate a high-temperature plasma airflow generated by an arc heater arranged upstream of the wind tunnel. In an arc heating wind tunnel test device that exhausts and heats a specimen supported in the wind tunnel so as to be movable in the flow direction of the plasma airflow, the diffuser can expand and contract in the flow direction of the plasma airflow. An arc heating wind tunnel test device characterized by being configured.