JPH0716983Y2 - Gas temperature measurement probe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a probe for measuring the gas temperature inside a combustion engine such as a gas turbine or a jet engine, and more specifically to avoid the influence of radiant heat from the surroundings. The present invention relates to a gas temperature measuring probe having a structure capable of highly accurate temperature measurement.

[Conventional technology]

Conventionally, as shown in FIG. (8), as a gas temperature measuring probe for measuring the temperature inside the gas supply pipe, both end openings a,
The temperature-sensing portion d of the temperature measuring element c is located in the center of the inside of the cylindrical shielding tube b which has been a, penetrating the wall of the shielding tube b, and the shielding tube b is opened through the openings a, a of the gas flow. It is known that the gas supply pipe f is suspended from the inner wall g of the gas supply pipe f via a support cylinder e in a state of being directed.

[Problems to be solved by the device]

The reason why the temperature-measuring element c is covered with the shielding cylinder b is to prevent the influence of radiant heat from the surroundings on the temperature-measuring element c. However, in this configuration, the temperature-sensing portion d of the temperature-measuring element c and the shielding cylinder b are covered. Although it is possible to prevent radiant heat from outside the range of the straight line connecting the opening edge h, that is, outside the range of the angles shown as α and β in the figure, it is not possible to prevent the radiant heat from within the range, and for example, gas transfer It was not possible to completely eliminate the temperature measurement error due to the radiant heat from the inner wall of the feed pipe. In order to solve this problem, it is considered to lengthen the shielding tube b, but there is a limit to the length because the restriction on the attachment to the gas supply pipe f and the influence of the wind pressure due to the gas flow cannot be ignored. is there. Also, as another method, it is considered to reduce the inner diameter of the shielding cylinder b, but in this case, the length of the temperature sensing portion d formed to project in the shielding cylinder b becomes insufficient, and as a result, gas There was a problem that the contact area of was insufficient and the value was lower than the true gas temperature.

The present invention has been made in view of the current situation.It is possible to measure the gas temperature with high accuracy without being affected by radiant heat from the surroundings. Moreover, the device configuration is compact and the installation is easy. It is an object of the present invention to provide a gas temperature measuring probe having a structure that withstands even the above and having excellent durability.

[Means for Solving the Problems]

The present invention which achieves the above object is expressed as the following two typical forms. In the first embodiment, a pair of gutter-shaped outer wall plates each having an arc-shaped cross section are arranged so as to face each other with a temperature measuring element therebetween to form an inlet on the upstream side of the gas flow and an outlet on the downstream side. A shielding plate inclined toward the downstream side is extended at the upstream end of the with a free space between the other outer wall plate and the opposite outer wall plate. The shielding plate inclined toward the upstream side was arranged in parallel with the shielding plate with the temperature measuring element sandwiched between them, and the temperature measuring element was made invisible from the surroundings and surrounded by the outer wall plate. It is characterized in that a gas flow path continuous from the inlet to the outlet is formed in the space.

The inlet cross-sectional area of the gas flow path formed by the shielding plate is preferably set to be larger than the cross-sectional area of the portion where the temperature sensing portion of the temperature measuring element is located and smaller than or equal to the outlet cross-sectional area.

Further, it is also appropriately adopted to attach a fin to the temperature sensing portion of the temperature measuring element to increase the contact area with the gas.

The second form has the following configuration. That is, a pair of gutter-shaped outer wall plates having an arcuate cross section are arranged so as to be offset from each other in the radial direction, and a substantially S-shaped gas flow path having an inlet on the upstream side of the gas flow and an outlet on the downstream side is provided. It is formed between the outer wall materials, and the temperature is measured by positioning the temperature measuring element at a position sandwiched between the inner surface of the outer edge of one outer wall material and the inner surface of the outer edge material of the other outer wall material, which is a substantially intermediate position of the gas flow path. The element is invisible from the surroundings, and the cross-sectional area of the gas flow passage in the portion where the temperature sensing portion of the temperature measuring element is located is set smaller than the cross-sectional area of the inlet of the gas flow passage.

[Action]

The gas temperature measuring probe of the present invention is positioned in the gas flow with the inlet directed upstream and the outlet directed downstream in the flow direction of the gas flow. The gas flowing from the inlet is guided to the temperature measuring element by being guided by the shielding material, comes into contact with the temperature sensing portion of the temperature measuring element, and then flows out from the outlet. Since the temperature measuring element is made invisible from the outside of the device by the shielding material over the entire surroundings, the radiant heat is completely blocked, and the gas temperature can be measured with high accuracy.

Further, since the present probe of the first embodiment has the inclined surface from the gas flow upstream to the downstream, the gas flow is smoothly guided by the inclined surface.

Further, when the cross-sectional area of the portion of the gas flow path where the temperature-sensitive portion is set is set smaller than the inlet cross-sectional area, the flow velocity around the temperature-sensitive portion is increased, and the responsiveness of the temperature-sensitive portion to the gas temperature is further enhanced. Further, when the fins are attached to the temperature sensing part, the contact area with the gas is increased and the responsiveness of the temperature sensing part is improved, and the mechanical strength of the temperature sensing part is simultaneously increased.

Further, in the probe of the second embodiment, the gas flow path is substantially S-shaped, so that the gas flow is guided more smoothly and the flow is not disturbed. Moreover, in the probe of the second embodiment, the cross-sectional area of the gas flow passage in the portion where the temperature sensing portion of the temperature measuring element is positioned is set smaller than the cross-sectional area of the gas flow passage inlet, so that the flow velocity around the temperature sensing portion is faster. Excellent responsiveness.

〔Example〕

 Next, the details of the present invention will be described based on the illustrated embodiment.

FIG. 1 is a cross-sectional explanatory view showing the entire structure of a gas temperature measuring probe according to the present invention. In this probe A, a temperature measuring element 2 such as a thermocouple is inserted into the cylindrical support member 1 made of silicon carbide (sic), and the tip of the temperature measuring element 2 is projected about 20 mm from the tip of the support member and the surroundings of the protruding temperature measuring element 2. Is covered with an exterior body 3 having a specific structure. The detailed structure around the exterior body 3 is shown in FIGS. 2 and 3 (a) (b) (c).

FIG. 2 shows a state before the exterior body 3 is assembled, and FIG.
FIG. 3C is a vertical sectional view in an assembled state, and FIG. 3B is a horizontal sectional view. As shown in the figure, the tip structure of this probe is such that the gutter-shaped outer wall plates 4a and 4b having an arc-shaped cross section are arranged so as to face each other with the temperature measuring element 2 interposed therebetween, and the inlet 5 is provided on the upstream side in the flow direction of the gas flow, and An outlet 6 is formed on the side, and a shield plate 7a inclined toward the downstream from the upstream tip is formed at the upstream tip of the outer wall plate 4a in the gas flow direction.
Is extended with a gap provided between the outer end of the outer wall plate 4b and the outer wall plate 4b facing the free end of the outer wall plate 4b. By disposing the shield plate 7b inclined toward the upstream side in parallel with the shield plate 7a, a continuous gas flow path from the inlet to the outlet is formed via the periphery of the temperature measuring element.

The dimensional relationship between the outer wall plates 4a and 4b and the shielding plates 7a and 7b is set on the basis of two points that the temperature measuring element 2 is not directly visible from the outside and that gas flows smoothly. Entrance 5
The opening width of the outlet 6 can be appropriately set as long as the above conditions are satisfied, but if the opening width is increased, the shielding plates 7a and 7b need to be long in order to make the temperature measuring element 2 invisible.
However, if the shield plates 7a and 7b are long, the gap between the outer wall plates facing each other is narrowed, and the gas flow may be hindered. In the present embodiment, in consideration of these circumstances, the angle formed by the temperature measuring element and the opening edge of the inlet is set to about 60 °. Further, regarding the size relationship of the sizes of the flow paths in the portions where the inlet 5 and the outlet 6 and the temperature measuring element 2 are located,
When S1, the cross-sectional area of the outlet 6 is S3, and the cross-sectional area of the portion where the temperature measuring element 2 is located is S2, it is preferable to set so as to satisfy the relationship of S3 ≧ S1> S2. The flow velocity of the gas flow passing around the temperature sensor 2 becomes faster and the temperature sensor 2
Responsiveness is improved.

In the space surrounded by the shield plates 7a and 7b, a support plate 8 having a substantially U-shape in front view is arranged to support the temperature measuring element 2 in an inserted state. The support plate 8 is intended to reinforce the temperature measuring element 2 exposed to the gas flow and prevent breakage.
Further, the support plate 8 is not in contact with the shield plates 7a, 7b and the outer wall plates 4a, 4b, and the support position of the temperature measuring element 2 is also a position separated from the temperature sensing part 9 by a certain distance, so that the support member 1 and the shield member are shielded. Board 7
The heat conduction between a and 7b and the temperature sensing portion 9 is cut off. The support plate 8 may be omitted if the temperature measuring element 2 has sufficient strength. The bottom plate 10 is attached to the lower end surfaces of the outer wall plates 4a and 4b, and the lower surfaces of the outer wall plates 4a and 4b are closed. By the way, the outer wall plates 4a, 4b, the shielding plates 7a, 7b, and the bottom plate 10 need to be formed of a material having high heat resistance, excellent heat conduction, and low emissivity. If the heat conduction of the outer wall plate and the bottom plate is low, a temperature difference may occur between the temperature sensing unit 9 and the outer wall plate and the bottom plate, and an error due to radiant heat may occur. In this embodiment, a thin plate made of platinum is used to realize high heat resistance and response, and further low emissivity, but other materials can be selected depending on the tolerance of the temperature measurement value. .

Further, as a heat influence on the temperature sensing portion 9, a loss due to heat conduction to the support member 1 cannot be ignored. In order to reduce the loss, as long as the mechanical strength of the temperature measuring element 2 permits, the support member 1
It is preferable to set a long protruding length from. In this embodiment, the temperature measuring element having a diameter of 1.6 mm is projected by 16 mm to 18 mm.

FIG. 4 shows a case in which fins 11 are attached to the temperature sensing portion 9 to increase the contact area with the gas in order to enhance the responsiveness of the temperature sensing portion 9. The fins 11 also have the effect of reinforcing the mechanical strength of the temperature sensing section 9.

The representative embodiment of the present invention has been described above. The exterior body 3 of the present invention shields the temperature measuring element 2 from radiation by shielding it from the surroundings, and at the same time, detects the gas flow.
It may have any other shape as long as it has a flow passage that can be smoothly guided. For example, as shown in FIG. 5, gutter-shaped outer wall plates 14a and 14b having arcuate cross sections are arranged so as to be offset from each other and face each other. Then, a substantially S-shaped gas flow path is formed between the gutter-shaped outer wall plates 14a and 14b, and the temperature measuring element 2 is arranged at a substantially intermediate position of the gas flow path and invisible to the surroundings. It is also possible to employ a gas flow passage having a cross-sectional area smaller than that of the gas flow passage at the inlet of the temperature measuring element. In this form of probe, the gas flow path is substantially S-shaped and there are no corners, so the gas flow is extremely smooth. Moreover, since the flow velocity of the gas passing through the temperature sensing portion is increased, the responsiveness is also excellent.

Such a configuration, in particular, the gas temperature measuring probe shown in FIGS. 1 to 3 has a combustor as shown in FIG. 7, for example.
In order to measure the temperature inside the connecting portion 17 made of a refractory material provided between the 15 and the desuperheater 16, the connecting portion 17 is penetrated and the tip thereof is positioned in the approximate center of the gas flow path 18 and attached. . The gas flow introduced from the inlet 5 positioned on the upstream side in the flow direction of the gas flow is guided by the outer wall plates 4a and 4b and the shielding plates 7a and 7b to pass around the temperature measuring element, and then discharged from the outlet 6. The details are shown in FIG. (6). That is, the gas flowing from the inlet 5 is guided to the outer wall plate 4b on the opposite side of the shield plate 7a, and
After wrapping around in the space formed between a and 7b and contacting the temperature sensing part 9 to convey the gas temperature, it is guided to the outlet 6 by being guided by the shield plate 7b and the outer wall plate 4a on the opposite side. At this time, since the shielding plates 7a and 7b are inclined with respect to the gas flow, the passage of the gas flow is smoothly performed without being obstructed. The temperature measuring element 2 is completely radiated and shielded by the outer wall plates 4a, 4b and the shield plates 7a, 7b in all directions, and therefore is affected by the radiant heat from the inner wall of the temperature reducer 16 and the inner wall of the combustor 15. It is possible to measure the gas temperature with high accuracy without any need.

Further, in the embodiment of the illustrated example, the cross-sectional area of the portion where the temperature sensing portion 9 is located is set smaller than the cross-sectional area of the inlet 5, so that the gas flow passage speed is high in the vicinity of the temperature sensing portion. The response of the warm part 9 to the gas temperature is extremely high.

The table shows the results of measuring the temperature of the connecting portion 17 by using the probe according to the present invention shown in FIG. 1 and the conventional probe shown in FIG. (8). In addition, the flow velocity of the temperature measurement target gas is 62 m / S, the gas pressure is about 1 atm, and the theoretical value of the average temperature in the gas flow cross-sectional area is 1270 ° C. The inner wall temperature of each part of the gas flow path as the measurement environment is Combustor 15 is 600 ℃, desuperheater 16
Was 20 ℃ ~ 50 ℃, the refractory material 17 was about 1000 ℃. The measurement was performed at a plurality of measurement points on the same cross section of the gas flow path, and the average temperature of the gas flow cross-sectional area was calculated based on these temperature measurement results.

As can be seen from the table, the temperature measured by the conventional product was 970 ° C, which was about 300 ° C different from the theoretical value (1270 ° C). This is because the inner surface temperature of the combustor and the inner wall temperature of the desuperheater were lower than the gas temperature.Therefore, in the transfer of radiant heat between the temperature-sensitive part and these inner walls, the radiant heat from the temperature-sensitive part to the inner wall was greater. As a result, it is estimated that the temperature of the temperature sensing part dropped. On the other hand, the temperature measured by the device of the present invention is 1200 ° C, which is extremely close to the theoretical value (1270 ° C), and the probe according to the present invention can almost completely radiate heat from the surroundings. It turns out that they can be eliminated.

[Effect of device]

As described above, the gas temperature measuring probe according to the present invention is arranged such that a pair of gutter-shaped outer wall plates having an arc-shaped cross section are arranged to face each other with a temperature measuring element therebetween, and the gas flow has an inlet on the upstream side and an outlet on the downstream side. And the temperature measuring element is arranged in the middle of the gas flow path so as to be completely invisible from the surroundings. Therefore, the gas freely flows into the gas flow path and the gas temperature is transmitted to the temperature sensing part of the temperature measuring element, but since the temperature measuring element is completely shielded against the radiant heat, the radiant heat is radiated to the temperature measuring element. Does not act, the response is excellent, and the gas temperature can be measured with high accuracy.

In particular, in the probe according to claim 1, a shield plate inclined toward the downstream is provided at the upstream end of one outer wall plate with a gap provided between the shield plate and the other outer wall plate whose free end faces. , The other outer wall plate is provided with a shielding plate inclined from the downstream rear end thereof to the upstream end so as to reduce the air resistance to the gas flow, so that it can withstand wind pressure and has a temperature measuring element. The flow of gas around can be smooth.

Furthermore, when a fin is attached to the temperature sensing part of the temperature measuring element,
Improving the responsiveness of the temperature sensitive part and improving the mechanical strength of the temperature sensitive part are achieved at the same time.

Further, as described in claim 4, a pair of gutter-shaped outer wall plates having an arc-shaped cross section are arranged so as to be opposed to each other in the radial direction so as to form a smooth substantially S-shaped gas passage between the outer wall members. In addition, if the cross-sectional area of the gas flow path in the part where the temperature sensing element of the temperature sensing element is located is set smaller than the cross-sectional area of the gas flow path inlet, the air resistance to the gas flow becomes smaller and Therefore, it is possible to completely prevent the occurrence of turbulence in the flow and to make the gas flow smoother. Further, since the gas flow velocity around the temperature measuring element is increased, the responsiveness of the temperature sensing portion is also improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view showing the overall structure of an embodiment of a gas temperature measuring probe according to the present invention, FIG. 2 is an exploded explanatory view of the essential parts of the same embodiment, and FIG. A longitudinal sectional view of the main part of the example, FIG. 3B is a sectional view taken along the line AA in FIG. 3B, FIG. 3C is a sectional view taken along the line BB in FIG. 3B, and FIG. FIG. 5 is a cross-sectional explanatory view showing a modified example in which fins are attached to the temperature measuring element in the embodiment, FIG. 5 is another embodiment, FIG. 6 is an explanatory view showing the gas flow in the outer package, and FIG. An explanatory diagram showing a usage example and FIG. 8 are conventional examples. A: Probe, 1: Support member, 2: Temperature measuring element, 3: Exterior body,
4a, 4b: outer wall plate, 5: inlet, 6: outlet, 7a, 7b: shielding plate, 8: support plate, 9: temperature sensing part, 10: bottom plate, 11: fins, 14a, 14b: gutter-shaped outer wall plate, 15: combustor, 16: desuperheater, 17: connecting part, 18: gas flow path.

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-62-846 (JP, A)

Claims (4)

[Scope of utility model registration request] 1. A pair of gutter-shaped outer wall plates each having an arcuate cross section are arranged so as to face each other with a temperature measuring element interposed therebetween to form an inlet on the upstream side of the gas flow and an outlet on the downstream side. A shield plate inclined toward the downstream side is provided at the upstream end with a gap between the shield plate and the other outer wall plate facing the free end, and the other outer wall plate is upstream from the downstream rear end. A shield plate inclined toward the temperature sensor is arranged in parallel with the shield plate so as to be invisible from the surroundings and a space surrounded by an outer wall plate. A gas temperature measuring probe having a continuous gas flow passage formed therein from the inlet to the outlet. 2. An inlet cross-sectional area of the gas flow path formed by the shield plate is set to be larger than the cross-sectional area of the portion of the temperature sensing element where the temperature sensing portion is located and smaller than or equal to the outlet cross-sectional area. The probe for gas temperature measurement according to claim 1, wherein the probe is registered as a utility model. 3. A probe for gas temperature measurement according to claim 1 or 2, wherein fins are attached in the vicinity of the temperature sensing portion of the temperature measuring element. 4. A substantially S-shaped gas having a pair of trough-shaped outer wall plates each having an arcuate cross-section, which are opposed to each other in a state of being radially displaced from each other, having an inlet on the upstream side of the gas flow and an outlet on the downstream side. A flow path is formed between the outer wall members, and a temperature measuring element is provided at a position sandwiched between the inner surface of the outer edge member of one outer wall member and the inner surface of the outer edge member of the other outer wall member, which is a substantially intermediate position of the gas flow path. Positioning the temperature measuring element invisible from the surroundings, and measuring the gas temperature by setting the cross sectional area of the gas flow path at the portion where the temperature sensing part of the temperature measuring element is located smaller than the inlet cross section of the gas flow path. Probe.