CN1007753B

CN1007753B - Radiation-responsive apparatus

Info

Publication number: CN1007753B
Application number: CN 85105211
Authority: CN
Inventors: 梅森姆; 波恩达
Original assignee: Smiths Group PLC
Current assignee: Smiths Group PLC
Priority date: 1985-07-10
Filing date: 1985-07-10
Publication date: 1990-04-25
Also published as: CN85105211A

Abstract

The present invention relates to a radiation induction device. The device is provided with an inner tube, wherein a lens is arranged on the back part of the inner tube, and the junction of the front part and the back part of the inner tube are in a step shape with the front part with a small diameter and with an opening on the front end. An outer tube is sheathed with the outer part of the inner tube and is coaxial with the inner tube, an annular passage is arranged between the inner tube and the outer tube, a small hole smaller than the outer diameter of the front end of the inner tube and larger than the inner diameter of the inner tube is arranged on the front end of the outer tube, a gas inlet connected with the annular passage and positioned on the back part of the front end of the inner tube is arranged on the outer tube, and the area of the gas inlet is greater than a gap formed between the front end of the inner tube and the front end of the outer tube. Gas is led in the passage through the gas inlet and is discharged from a small hole on the front end of the inner tube. Thereby, constant pressure is basically kept on the back part of the inner tube, and the invasion of dirt is reduced.

Description

Radiation-responsive apparatus

The present invention relates to radiation-responsive apparatus, this device comprises an interior pipe of adorning radiation transparent window.

The present invention comparatively highlightedly but be not the radiation pyrometer that has related to uniquely such as being used for gas turbine.

The temperature of gas turbine blades can be measured by enough a kind of radiation pyrometers.It is to observe blade for the aperture that can see through on the motor body that pyrometer is installed.This pyrometer has lens at an end of pipe, when vanes is crossed the visual field of pyrometer, lens will the radiation heat of each blade directly or by the directing radiation device for example the light transmitting fiber optical cable focus on the radiation sensor.Lens are normally made as sapphire with heat proof material, perhaps are contained in the back of heat proof material window, can make it bear the high temperature and the temperature variation of engine like this.

The problem that this pyrometer exists is, carbon ash or other comburants of engine can be accumulated on the lens minute surface, thereby reduced the radiant quantity that sees through, in order to reduce the generation of this problem, proposed various method, for example on minute surface, used catalyzer (BrP GB2121978A) or use purify air (BrP GB1589531).

Purify air if use, then adorn an opening observation tube in pyrometer lens front, pyrometer passes the by-pass pipe of engine, and the front end of observation tube feeds the engine turbine firing chamber.An air intake is arranged on the observation tube, like this, from by-pass pipe or one independently the purified gas that comes out of purification plant enter observation tube and send into the turbine firing chamber from the observation tube front end, at this moment the air pressure of firing chamber is lower.Purifying air flows into through observation tube, has played the effect that reduces the heap of firing chamber dirt on lens.Though this method has reduced amount of contaminants really, also not a kind of method in full force and effect, because the mobile generation eddy current that purifies air can make some dirts bring into from the observation tube front end.

Purpose of the present invention is to provide a kind of pyrometer or similar device, reduces the pollution on lens or other window.

The invention provides the radiation-responsive apparatus of mentioned kind, it is characterized in that:

Pipe has a previous section, and the front end of this part is opening mouth;

Window is contained in the aft section of pipe;

The interior sectional area of aft section is greater than previous section;

This device comprises a gas passage, and its inlet is positioned at the pipe front end, and the gas of sending into air intake opening like this has at least a part to flow forward along passage, and the front end by pipe, thereby is keeping constant compression force in the aft section of pipe.Can reduce dirt like this and enter pipe.

Device preferably has an outer tube, and is coaxial with the previous section of interior pipe, thereby forms an annular gas passage along the outside of interior pipe front end.Outer tube can have a lip of folding inward, form the gap with the front end of interior pipe, gas goes out outer tube by interstitial row, and the inlet of gas can be on outer tube, and its inlet area is greater than the area in gap, the front end of outer tube has an aperture, aperture is less than the external diameter of interior pipe previous section, and greater than the internal diameter of interior pipe previous section, interior pipe is preferably in an interior step between previous section and the aft section, step can tilt, and radiation transparent window is lens preferably.

We demonstrate gas turbine radiation pyrometer of the present invention with reference to accompanying drawing now, wherein:

Fig. 1 is the profile in elevation of pyrometer,

Fig. 2 is the partial schematic diagram of another kind of pyrometer.

With reference to Fig. 1, as can be seen, pyrometer is roughly cylindrical, be contained on the gas turbine 2, its front end 10 sees through aperture and puts in 4 li of engine housings, the head 11 of pyrometer 1 cooperates with annular seating 5 on the turbine chamber wall 6 tightly, and the center in viewed straight-on hole 7 sees through hole 7 and can observe turbo blade 8 again.

Pyrometer 1 has an anti-corrosion alloy steel outer tube 15, covers whole pyrometer, and the rear end of outer tube 15 has flange 16 to form, and flange 16 is connected with similar flange 17 on the inner sleeve 18.Interior pipe 18 is stainless steel materials, and is the same long with outer tube 15 basically, and the front end of close interior pipe 18 has a slight gap 20, is used for the axial thermal expansion between inner and

outer pipes

18 and 15.

The front end 21 of light transmitting fiber optical cable 22 is contained in the rear portion of pyrometer, at the rear portion of mirror pipe 32.Link together with bolt 26 between mirror pipe 32 and inner and outer pipes 18 and 15.Mirror pipe 32 is anti-corrosion alloy steel, and frame sapphire lens 34.The sealing of sapphire lens is installed near the edge of pipe front end.

Interior pipe 18 parts in lens 34 fronts have formed an observation tube 41, and the internal diameter of observation tube 41 rear ends 43 is about 12 millimeters, and big have one tiltedly to take on 44 about the centre of observation tube 41, the one-tenth step, and diameter is 8 millimeters.The aft section diameter of observation tube 41 is bigger, with outer tube 15 wringing fits.The reduced diameter of its front end, thus circular passage 45 of formation between the tube and tube 15 observed.

Outer tube 15 tops are the lips 46 of folding inward, have formed diameter and be 9 millimeters circular hole 47.47 internal diameters greater than observation tube 41 front ends, but less than its external diameter, lip 46 has formed filleted corner 48, and lip and observation tube termination separate 1 millimeter approximately.Six inlets 50 that purify air are evenly distributed in around the outer tube 15, make the rear portion of gas from engine by-pass pipe 9 inflow circular passages 45, and discharge from the front end of observation tube 41.These six the area sums that enter hole 50 of purifying air have substantially exceeded the area in gap, just the minimum clearance place that forms between observation tube 41 and the lip 46.

During running, the radiation heat that pyrometer 1 turbo blade 8 within the vision produces can be focused on the termination 21 of optical cable 22 at last through the aperture 47 on viewport 7 and pyrometer top by lens 34.The field range of pyrometer depends on the size and the shape of the limit optical screen 33 on the optical cable 22 front mirror pipes 32, and radiation heat is delivered to a detecting device (not showing) by optical cable 22, and detecting device provides output signal according to temperature.

Input by-pass pipe 9 purifies air, its pressure substantially exceeds the gaseous tension in the turbine firing chamber, purify air and send into circular passage 45 between observation tube 41 and the outer tube 15 by air intake opening 50, it is mobile to go ahead, changed the flow direction by lip 46 at last, thereby have the front end of a part of gas stream at least, discharge from small-diameter hole 47 through observation tube 41.Gas stream is tending towards gas is extracted out outside the pipe through the front end of observation tube 41, so that causes little pressure drop in the bigger place of diameter, observation tube rear portion.

Gas is discharged pyrometer along viewport 7, and such gas flow makes most of dirt can not enter pyrometer.But because gas flow produces eddy current, the dirt of minute quantity still may enter the hole 47 of viewport 7 and pyrometer termination.Above the illustrated verified dirt that can reduce on the lens 34 of method, though understand wherein cutter reason really not clearly, but think that the partly cause that obtains this result may be because the gas responance post that sufficient gas flow forms causes in observation tube, the frequency of this resonance post depends on the size of pipe, the character of gas responance post is such, the pressure of any point all is constant basically on the resonance post, gas does not have overall mass exchange, thereby can imagine that the gas responance post that observation tube is 41 li has reduced and enters pipe and be accumulated in amount of contaminants on the lens 34.

Lower at gas flow, be not enough to form under the situation of resonance post, can imagine, the eddy current that the gas gas flow produces on observation tube 41 tops only only limits to the thinner part in observation tube front, and in fact pipe previous section and the step between the back thicker part branch become the obstacle of eddy current.

As shown in Figure 2, profile can be various.Layout according to Fig. 2, observation tube 141 is stepped to form narrow perforate 142 at the pipe end place, purified gas is sent into the circular passage 145 between observation tube 141 and the outer tube 146, and outer tube 146 has the contraction of section of a pipe 147 diameters to diminish on observation tube 141 tops, and extends forward along observation tube.

This will appreciate that the present invention is not confined to pyrometer, also can be used to contain other devices of easy contaminated light inlet window.Relevant this problem, the present invention is not limited only to use radiation sensor, also can find purposes on the radiation heat emitter, thereby reduces the pollution to transmission window.

Claims

1, radiation-responsive apparatus comprises an optical cable that is fixed on this device rear end, and the optical cable end is connected on the remote measurement radiation sensor, and above-mentioned radiation-responsive apparatus comprises the interior pipe of a band radiation transparent window, it is characterized in that:

Pipe (18,141) removes an opening part, and remainder is closed;

Window (34) is contained in the aft section (43) of pipe;

The interior sectional area of pipe aft section (43) is greater than previous section, and this aft section and previous section are separated from each other by an inner annular step (44);

Device comprises a gas passage (45), four air intake openings (50) of passage are positioned at the back location (18 of pipe front end, 141), the gas of sending into air intake opening (50) like this has at least a part to flow forward along passage (45), this passage has a surface structure (46), guiding at least a portion gas, and the front end (18 of the pipe of flowing through, 141), thus can keep constant gas pressure basically in the aft section (43) of pipe.

According to the radiation-responsive apparatus of claim 1, it is characterized in that 2, device comprises an outer tube (15,146), coaxial with the previous section (18,141) of interior pipe, thus formed a circular passage (45) in the outside of interior pipe front end.

3, according to the radiation-responsive apparatus of claim 2, it is characterized in that, described surface structure be one at outer tube (15,146) lip of rolling over inward on (46,147) is with the front end (18 of interior pipe, 141) form a gap, gas flows out outer tube (15,146) by this gap.

According to the radiation-responsive apparatus of claim 3, it is characterized in that 4, gas access (50) are positioned on the outer tube (15,146), the area of air intake opening is greater than the area in gap.

5, according to each radiation-responsive apparatus in the claim 2 to 4, it is characterized in that the front end of outer tube (15) has an aperture (47), aperture is less than the external diameter of the previous section (18) of interior pipe.

According to the radiation-responsive apparatus of claim 5, it is characterized in that 6, aperture (47) is greater than the internal diameter of the previous section (18) of interior pipe.

7, according to each radiation-responsive apparatus in the claim 1 to 4, it is characterized in that interior step (44) tilts.

8, according to each radiation-responsive apparatus in the claim 1 to 4, it is characterized in that radiation transparent window is lens (34).