CN114526552B - A hypersonic flow field heating device and heating method - Google Patents

Abstract

The invention relates to a hypersonic flow field heating device and heating method, comprising a pressure-bearing pipeline, the two ends of the pressure-bearing pipeline are respectively fixedly equipped with a first flange and a second flange, and the sealing surface of the first flange is provided with an electric heater The mounting seat, the sealing surface of the second flange is equipped with a special-shaped octagonal gasket, and the inner flow pipe is provided inside the pressure-bearing pipe. One end of the inner flow pipe is fixedly connected with the electric heating mounting seat, and the other end of the inner flow pipe goes deep into the The inside of the pressure-bearing pipe is assembled with a special-shaped octagonal pad. An electric heating tube is installed outside the inner runner tube. The electric heating tube is fixedly installed on the electric heating mounting seat. This device adopts the combined structure of the electric heating mounting seat, the inner runner tube and the special-shaped octagonal pad to ensure the heating efficiency and at the same time realize the flow form that does not affect the internal flow field of the heating pipeline. Electric heating installed.

Description

A hypersonic flow field heating device and heating method

technical field

The invention relates to the technical field of pipeline heating, in particular to a hypersonic flow field heating device and a heating method.

Background technique

The pipeline heater uses electricity as the energy source, uses efficient and durable electric heating elements as the heating element, converts the electrical energy into heat energy, and then transfers the heat to the medium to be heated through the medium transmission method, and can quickly heat the heating medium to the predetermined required temperature , The heating temperature is adjustable and controllable, and the heating temperature is always kept within the range of the safe rating. Commonly used pipeline electric heaters include two types, one is to heat the outside of the pipeline, and the heat is introduced into the medium in the pipeline by the pipe wall, and the other is to install a heating device inside the pipeline, but both methods exist With some questions:

1. The external heating of the pipeline is adopted, although it does not affect the flow of the medium inside the pipeline, but its heating efficiency is low, the energy consumption is high, and it cannot meet the occasions with high requirements;

2. The heating device is installed in the pipe, and the heating device is directly inserted into the pipe to cause certain disturbances to the flow of the medium inside the pipe, which affects the stability of the flow field.

Therefore, for occasions requiring heating that require relatively high heating efficiency and flow field stability (such as a supersonic flow field), it is necessary to provide a new pipeline heater.

Contents of the invention

In view of the disadvantages of low heating efficiency of the external pipeline heater, complex structure of the internal pipeline heater, inconvenient installation, and influence on the flow field of the medium inside the pipeline in the above-mentioned existing production technology, the applicant provides a hypersonic flow with reasonable structure The field heating device adopts internal heating and improves the internal heat transfer structure, inlet and outlet structure and installation method of the heating device to achieve efficient heat transfer, stabilize the flow field of the heating medium, and facilitate installation.

The technical scheme adopted in the present invention is as follows:

A hypersonic flow field heating device, comprising a pressure-bearing pipeline, the outside of the pressure-bearing pipeline is provided with an insulation layer, the two ends of the pressure-bearing pipeline are respectively fixedly equipped with a first flange and a second flange, and the first flange The sealing surface of the second flange is provided with an electric heating mounting seat, the sealing surface of the second flange is equipped with a special-shaped octagonal pad, and the inside of the pressure-bearing pipeline is provided with an inner runner tube, and one end of the inner runner tube is connected to the electric heating installation The seat is fixedly connected, the other end of the inner runner pipe goes deep into the pressure-bearing pipe and is fitted with a special-shaped octagonal pad, and an electric heating tube is installed outside the inner runner tube, and the electric heating tube is fixedly installed on the On the seat, one end of the electric heating tube passes through the outer circumferential surface of the electric heating mounting seat, and a temperature measuring core is fixedly installed on the outside of the inner runner tube, and the temperature measuring core is fixed on the electric heating mounting seat at the same time. One end of the temperature measuring core passes through the outer peripheral surface of the electric heating installation seat, and the outer circumference of the electric heating tube and the temperature measuring core is covered with an inner heat insulation layer concentric with the pressure-bearing pipeline.

Its further technical scheme is:

The structure of the electric heating mounting seat is as follows: it includes a ring-shaped electric heating mounting seat body, a boss is formed on one side of the electric heating mounting seat body, the outer diameter of the boss is smaller than the outer circumference diameter of the electric heating mounting seat body, and the outer side of the boss A mating sealing surface is formed on the main body of the electric heating mounting seat, and a tapered through hole expanding toward the end surface of the boss is opened inside the boss, and the other side of the electric heating mounting seat body forms a mounting sealing surface, and the mounting sealing surface and the The sealing surface of the first flange cooperates, and an annular counterbore is opened on the installation sealing surface, the annular counterbore is concentric with the tapered through hole, and a plurality of inner flow channels are opened on the bottom surface of the annular counterbore The installation holes of the inner runner pipe are threaded blind holes, and the installation holes of the inner runner pipe are evenly distributed along the circle concentric with the annular counterbore. The heating tube piercing hole and the temperature measuring core piercing hole, the electric heating pipe piercing hole is installed with the electric heating pipe piercing pipe, the temperature measuring core piercing hole is equipped with the temperature measuring core piercing pipe, so An electric heating tube is installed in the hole for the electric heating tube and the tube for the electric heating tube, and a temperature measuring core is installed in the hole for the temperature measuring core and the tube for the temperature measuring core.

The structure of the special-shaped octagonal pad is: comprising a ring-shaped special-shaped octagonal pad body, the central hole of the special-shaped octagonal pad body is a tapered through hole, and the two end faces of the special-shaped octagonal pad body form an octagonal sealing surface. The peripheral surface of the special-shaped octagonal pad body is provided with a safety valve installation hole and a pressure relief hole, a safety valve installation pipe is installed on the safety valve installation hole, and a pressure relief valve installation pipe is installed on the pressure relief hole.

The octagonal sealing surface is an annular raised structure.

The inside of the inner runner pipe is a cylindrical through hole, the outer structure of the inner runner pipe includes a tapered pipe section formed at one end of the inner runner pipe, the outer wall of the tapered pipe section is inclined to the other end of the inner runner pipe, The other end of the inner runner pipe forms an annular mounting boss outside, and the part connected to the mounting boss is a mounting section, and a groove section is arranged between the mounting section and the tapered pipe section, and the grooved section The outer diameter is less than or equal to the minimum outer diameter of the installation section and the tapered pipe section.

The end face of the mounting boss is provided with a plurality of bolt holes, and the bolt holes are evenly distributed along the circumference concentric with the inner runner pipe, and the outer end face of the mounting boss is provided with a plurality of first U-shaped notches, so The first U-shaped notch passes through the outer wall of the installation section, and an electric heating tube installation groove is formed on the outer wall of the installation section, and a plurality of second U-shaped notches are opened on the outer end surface of the installation boss. The shaped notch passes through the pipe wall of the installation section, and forms a temperature measuring core installation groove on the outer wall of the installation section.

The first flange is connected to the electric heating mounting seat through a gasket.

The pads are octagonal pads.

Compensation electric heating tubes and thermocouples are fixedly installed on the outer peripheral surfaces of the first flange and the second flange.

A heating method for a hypersonic flow field heating device, comprising the following steps:

The first step, design:

By designing the structure of the hypersonic flow field heating device to match the required heating pipeline, such as the length and thickness of the pressure-bearing pipeline, and the corresponding first flange, second flange, electric heating mounting seat, special-shaped octagonal pad, heating pipe and inner runner tubes;

The second step, manufacturing:

Manufacture related components of hypersonic flow field heating device according to design standards and drawings;

The third step is to assemble the hypersonic flow field heating device:

Install the electric heating tube and temperature measuring core on the corresponding position of the electric heating mounting base;

Then pass the electric heating tube and the temperature measuring core through the first U-shaped notch and the second U-shaped notch on the inner runner tube, and fit the bolt hole with the inner runner tube installation hole on the installation boss through bolts Install, and then install the electric heating tube and the temperature measuring core on the electric heating tube installation groove and the temperature measuring core installation groove;

Put the inner heat insulation layer on the outside of the electric heating tube and the temperature measuring core, and at the same time set the gasket to install the gasket on the installation sealing surface of the electric heating mounting seat;

Then insert the above-installed components into the pressure-bearing pipeline;

The center hole of the special-shaped octagonal gasket body is matched with the tapered pipe section of the inner runner pipe, and the octagonal sealing surface is sealed and connected with the sealing surface of the second flange;

The fourth step, install in the experimental pipeline:

Connect the mating sealing surface of the electric heating mounting seat of the hypersonic flow field heating device to the first mating flange of the required heating pipeline through a gasket, and at the same time, the boss is deeply matched with the inner hole of the first mating flange, and then bolts are used to Fastening the first flange and the first mating flange;

Then connect the special-shaped octagonal gasket to the second matching flange through the octagonal sealing surface, and fasten the second flange to the second matching flange through bolts;

The fifth step, connect the external line:

Connect the external lines of the electric heating tube and the temperature measuring tube, connect the external lines of the compensation electric heating tube and the thermocouple, install the safety valve on the safety valve installation pipe, install the pressure relief valve and pressure detection on the pressure relief valve installation pipe device, connecting the above-mentioned circuit and detection device with the control system;

The sixth step, parameter setting:

Turn on the hypersonic flow field heating device and control system power supply, and set the heating parameters and temperature and pressure control parameters;

The seventh step, heating and heat preservation:

Start the heating function of the hypersonic flow field heating device. The heating process is divided into two stages for heating. In the first stage, the electric heating tube outputs full power, and the temperature of the pressure-bearing pipeline medium quickly rises to the set temperature. In the second stage, the output power of the electric heating tube Gradually reduce the heat preservation of the entire system. After a period of heat preservation, the surface temperature of the medium in the pipeline and the inner flow channel will gradually converge, and the uniformity of the medium temperature in the pressure-bearing pipeline will gradually meet the technical index requirements. At this time, follow-up can be carried out. Test operation.

The beneficial effects of the present invention are as follows:

The invention has a compact and reasonable structure, and is easy to operate. By optimizing the structure of the internal pipeline heater, the combined structure of the electric heating mounting seat, the inner flow channel tube and the special-shaped octagonal pad is adopted to ensure the heating efficiency and at the same time realize that the internal flow field of the heating pipeline is not affected. The flow form provides an easy-to-install electric heating device for the high-precision requirements of the flow field.

Simultaneously, the present invention also has the following advantages:

(1) Adopt the internal heating structure, set the inner runner tube in the pressure pipeline, and install the electric heating tube on the outer wall of the inner runner tube, the electric heating tube is covered with an inner heat insulation layer, and transfer heat through the inner runner tube The form heats the medium inside the pressure-bearing pipeline, and the medium flows through the inside of the inner runner tube without affecting the shape of the flow field. At the same time, the inner heat insulation layer can reduce the temperature of the pressure-bearing pipeline and reduce heat loss.

(2) The structure in which the electric heating tube and the temperature measuring core are led out from the circumferential surface of the electric heating mounting seat is adopted. The design is ingenious, and the installation of the electric heating tube can be realized in a very small space. At the same time, the boss structure is assembled with the first matching flange And the design of the tapered through hole reduces the gap at the connection and can realize the minimum interference to the fluid flow field at the outlet of the device.

(3) The special-shaped octagonal pad structure is adopted, which avoids the problem of a large gap between the second flange and the second matching flange due to the conventional installation, and at the same time, the center hole and the tapered pipe section of the inner flow pipe are matched with the structure of the sleeve , when the inner runner tube is heated and expanded, it can not slide in the center hole, so as to ensure the straightness of the inner runner tube itself and the coaxiality with the pressure-bearing pipe, thereby ensuring that the shape of the fluid flow field is not affected.

(4) The flange at the inlet and outlet adopts the form of compensatory heating to further reduce the influence of temperature changes on the flow form of the flow field by reducing the temperature difference.

Description of drawings

Fig. 1 is a structural schematic diagram of the present invention (including matching flange 1 and matching flange 2).

Fig. 2 is an exploded view of the first flange side (including the first mating flange) of the present invention.

Fig. 3 is an exploded view of the second flange side of the present invention (including the second mating flange).

Fig. 4 is a front view of the present invention (including matching flange 1 and matching flange 2).

FIG. 5 is a cross-sectional view along line A-A of FIG. 4 .

Fig. 6 is a perspective view of the electrothermal installation seat of the present invention.

Fig. 7 is a front view of the electric heating mounting seat of the present invention.

Fig. 8 is a B-B sectional view of Fig. 7 .

Fig. 9 is an axonometric view of the special-shaped octagonal pad of the present invention.

Fig. 10 is a front view of the special-shaped octagonal pad of the present invention.

FIG. 11 is a C-C sectional view of FIG. 10 .

Fig. 12 is an isometric view of the inner channel pipe of the present invention.

Fig. 13 is a front view of the inner runner tube of the present invention.

Fig. 14 is an axial sectional view of the inner runner tube of the present invention.

Fig. 15 is a side view of the inner runner tube of the present invention.

Among them: 1. Pressure pipe; 2. First flange; 3. Second flange; 4. Electric heating mounting seat; 5. Special-shaped octagonal pad; 6. Inner flow pipe; 7. Electric heating pipe; Warm core; 9. Inner insulation layer; 10. Gasket; 11. Compensation electric heating tube; 12. Thermocouple; 13. First matching flange; 14. Second matching flange;

401. Electric heating mounting seat body; 402. Boss; 403. Matching sealing surface; 404. Installation sealing surface; 405. Electric heating tube piercing hole; 406. Temperature measuring core piercing hole; 407. Inner flow pipe installation hole ; 408, the electric heating tube goes out of the tube; 409, the temperature measuring core goes out of the tube;

501, special-shaped octagonal pad body; 502, central hole; 503, octagonal sealing surface; 504, safety valve installation hole; 505, pressure relief hole; 506, safety valve installation pipe; 507, pressure relief valve installation pipe;

601, tapered pipe section; 602, installation boss; 603, installation section; 604, groove section; 605, bolt hole; 606, first U-shaped notch; 607, electric heating tube installation groove; 608, second U-shaped notch ; 609, temperature measuring core installation groove.

Detailed ways

The specific implementation manner of the present invention will be described below in conjunction with the accompanying drawings.

As shown in Figure 1, the hypersonic flow field heating device of this embodiment includes a pressure-bearing pipeline 1, an insulation layer is provided outside the pressure-bearing pipeline 1, and a first flange 2 and a second flange 2 are fixedly installed at both ends of the pressure-bearing pipeline 1, respectively. Two flanges 3, the sealing surface of the first flange 2 is provided with an electric heating mounting seat 4, the sealing surface of the second flange 3 is installed with a special-shaped octagonal gasket 5, and the pressure-bearing pipeline 1 is provided with an inner flow pipe 6, One end of the inner runner tube 6 is fixedly connected with the electric heating mounting seat 4, and the other end of the inner runner tube 6 penetrates into the pressure-bearing pipeline 1 and fits with the special-shaped octagonal pad 5, and an electric heating tube is installed outside the inner runner tube 6 7. The electric heating tube 7 is fixedly installed on the electric heating mounting base 4, and one end of the electric heating tube 7 passes through the outer circumferential surface of the electric heating mounting base 4, and a temperature measuring core 8 is fixedly installed on the outside of the inner runner tube 6, and the temperature measuring core 8 is fixed on the electric heating mounting base 4 at the same time, one end of the temperature measuring core 8 passes through the outer peripheral surface of the electric heating mounting base 4, and the outer circumference of the electric heating tube 7 and the temperature measuring core 8 is covered with an inner heat insulation concentric with the pressure pipe 1 Layer 9. The inner runner tube 6 is set in the pressure pipeline, and the electric heating tube 7 is installed on the outer wall of the inner runner tube 6, and the inner medium of the pressure pipeline is heated through the heat transfer form of the inner runner tube 6, and the medium flows through the inner The inside of the runner tube 6 does not affect the shape of the flow field. At the same time, the inner heat insulation layer 9 outside the electric heating tube 7 can reduce the temperature of the pressure-bearing pipeline 1 and reduce heat loss. The overall design structure can be disassembled.

As shown in Figures 6-8, the structure of the electric heating mounting seat 4 is as follows: it includes a ring-shaped electric heating mounting seat body 401, and a boss 402 is formed on one side of the electric heating mounting seat body 401, and the outer diameter of the boss 402 is smaller than that of the electric heating mounting seat body 401. Circumferential diameter, on the outer side of the boss 402, the electric heating mounting seat body 401 forms a matching sealing surface 403, and the inside of the boss 402 has a tapered through hole that expands toward the end face of the boss 402, and the other side of the electric heating mounting seat body 401 forms a mounting The sealing surface 404, the installation sealing surface 404 cooperates with the sealing surface of the first flange 2, the installation sealing surface 404 is provided with an annular counterbore, the annular counterbore is concentric with the tapered through hole, and the bottom surface of the annular counterbore is provided with a plurality of Inner runner pipe installation holes 407, the inner runner pipe installation holes 407 are threaded blind holes, the inner runner pipe installation holes 407 are evenly distributed along a circle concentric with the annular counterbore, and the circumferential surface of the annular counterbore is provided with a plurality of electric holes. Heating tube piercing hole 405 and temperature measuring core piercing hole 406, electric heating pipe piercing hole 405 is installed with electric heating pipe piercing pipe 408, temperature measuring core piercing hole 406 is equipped with temperature measuring core piercing pipe 409 , the electric heating tube piercing hole 405 and the electric heating tube piercing tube 408 are equipped with an electric heating tube 7, and the temperature measuring core piercing hole 406 and the temperature measuring core piercing tube 409 are equipped with a temperature measuring core 8. The structure in which the electric heating tube 7 and the temperature measuring core 8 are led out from the circumferential surface of the electric heating mounting seat 4 is ingeniously designed to realize the installation of the electric heating tube 7 in a very small space. At the same time, the matching between the boss 402 and the first matching flange 13 The design of the device and the tapered through hole reduces the gap at the connection, and can realize the minimum interference to the fluid flow field at the outlet of the device.

As shown in Figure 9-Figure 11, the structure of special-shaped octagonal pad 5 is: comprise annular special-shaped octagonal pad body 501, the central hole 502 of special-shaped octagonal pad body 501 is a tapered through hole, two end faces of special-shaped octagonal pad body 501 An octagonal sealing surface 503 is formed at the place, and a safety valve installation hole 504 and a pressure relief hole 505 are opened on the peripheral surface of the special-shaped octagonal pad body 501. A safety valve installation pipe 506 is installed on the safety valve installation hole 504, and a safety valve installation pipe 506 is installed on the pressure relief hole 505 Pressure relief valve mounting tube 507. The structure of the special-shaped octagonal pad 5 is used to replace the conventional flange sealing gasket, which avoids the problem of a large gap between the second flange 3 and the second matching flange 14 due to the conventional installation. The safety valve installation hole 504 and the pressure relief hole 505 are set at the inlet of the medium, which have the least impact on the test flow field.

The octagonal sealing surface 503 is an annular convex structure.

As shown in Figures 12-15, the inside of the inner runner pipe 6 is a cylindrical through hole, and the outer structure of the inner runner pipe 6 includes a tapered pipe section 601 formed at one end of the inner runner pipe 6, and the outer wall of the tapered pipe section 601 faces The other end of the inner runner pipe 6 is inclined, and the other end of the inner runner pipe 6 forms an annular mounting boss 602 outside, and the part connected to the mounting boss 602 is the installation section 603, and a groove is arranged between the installation section 603 and the tapered pipe section 601 Section 604 , the outer diameter of the grooved section 604 is less than or equal to the minimum outer diameter of the installation section 603 and the tapered pipe section 601 . The center hole 502 of the special-shaped octagonal pad 5 is matched with the tapered pipe section 601 of the inner runner pipe 6 and has a certain matching gap structure, so that when the inner runner pipe 6 is heated and expanded, it can slide in the center hole 502, releasing the axial and The radial thermal displacement ensures the straightness of the inner runner pipe 6 and the coaxiality with the pressure-bearing pipe 1, thereby ensuring that the shape of the fluid flow field is not affected.

As shown in Figure 13 and Figure 5, the end surface of the mounting boss 602 is provided with a plurality of bolt holes 605, the bolt holes 605 are evenly distributed along the circumference concentric with the inner runner pipe 6, and the outer end surface of the mounting boss 602 is provided with multiple bolt holes. A first U-shaped notch 606, the first U-shaped notch 606 passes through the outer wall of the installation section 603, and forms an electric heating tube installation groove 607 on the outer wall of the installation section 603, and a plurality of first U-shaped notches 602 are provided on the outer end surface of the installation boss 602 Two U-shaped notches 608 , the second U-shaped notch 608 passes through the pipe wall of the installation section 603 , and forms a temperature measuring core installation groove 609 on the outer wall of the installation section 603 . There are multiple electric heating tube installation slots 607 and temperature measurement core installation slots 609 on the installation section 603, which are used to locate the electric heating tube and temperature measurement elements, and can be divided into upper half pipe heating and temperature measurement and lower half pipe heating and temperature measurement , to ensure scientific and reasonable heating and temperature control.

The first flange 2 is connected with the electric heating mounting base 4 through the gasket 10 .

Pad 10 is an octagonal pad.

Compensation electric heating tubes 11 and thermocouples 12 are fixedly installed on the outer peripheral surfaces of the first flange 2 and the second flange 3 . The flange at the inlet and outlet adopts the form of compensatory heating to further reduce the influence of temperature changes on the flow form of the flow field by reducing the temperature difference.

Embodiment one:

The heating method of the hypersonic flow field heating device of this embodiment includes the following steps:

The first step, design:

By designing the structure of the hypersonic flow field heating device to match the required heating pipeline, such as the length and thickness of the pressure-bearing pipeline 1, and the corresponding first flange 2, second flange 3, electric heating mounting seat 4, and special-shaped octagonal Pad 5, heating pipe 7 and inner runner pipe 6;

The second step, manufacturing:

Manufacture related components of hypersonic flow field heating device according to design standards and drawings;

The third step is to assemble the hypersonic flow field heating device:

Install the electric heating tube 7 and the temperature measuring core 8 on the corresponding position of the electric heating mounting base 4;

Then the electric heating tube 7 and the temperature measuring core 8 are passed through the first U-shaped notch 606 and the second U-shaped notch 608 on the inner flow channel tube 6, and the bolt hole 605 is connected with the inner flow on the installation boss 602. The pipe installation hole 407 is fitted with bolts, and then the electric heating tube 7 and the temperature measurement core 8 are installed on the electric heating tube installation groove 607 and the temperature measurement core installation groove 609;

Put the inner heat insulation layer 9 on the outside of the electric heating tube 7 and the temperature measuring core 8, and at the same time install the gasket 10 on the installation sealing surface 404 of the electric heating mounting seat 4;

Then insert the above-installed components into the pressure-bearing pipeline 1;

The central hole 502 of the special-shaped octagonal gasket body 501 is fitted together with the tapered pipe section 601 of the inner runner pipe 6, and the octagonal sealing surface 503 is sealed and connected with the sealing surface of the second flange 3;

The fourth step, install in the experimental pipeline:

Connect the mating sealing surface 403 of the electrothermal mounting seat 4 of the hypersonic flow field heating device to the first mating flange 13 of the required heating pipeline through the gasket 10, and at the same time, the boss 402 goes deep into the inner hole of the mating first mating flange 13 , then use bolts to fasten the first flange 2 and the first matching flange 13;

Then the special-shaped octagonal gasket 5 is connected to the second matching flange 14 through the octagonal sealing surface 503, and the second flange 3 and the second matching flange 14 are fastened by bolts;

The fifth step, connect the external line:

Connect the external lines of the electric heating tube 7 and the temperature measuring tube 8, connect the external lines of the compensation electric heating tube 11 and the thermocouple 12, install the safety valve on the safety valve installation pipe 506, and install the pressure relief valve on the pressure relief valve installation pipe 507. Pressure relief valve and pressure detection device, connecting the above-mentioned lines and detection device with the control system;

The sixth step, parameter setting:

Turn on the hypersonic flow field heating device and control system power supply, and set the heating parameters and temperature and pressure control parameters;

The seventh step, heating and heat preservation:

Start the heating function of the hypersonic flow field heating device. The heating process is divided into two stages for heating. In the first stage, the electric heating tube 7 outputs full power, and the medium temperature of the pressure-bearing pipeline 1 rises rapidly to the set temperature. In the second stage, the electric heating tube 7 The output power is gradually reduced, and the entire system is kept warm. After a period of heat preservation, the surface temperature of the medium in the pipeline and the inner flow channel gradually converge, and the uniformity of the medium temperature in the pressure-bearing pipeline 1 also gradually meets the technical index requirements. Subsequent test operations can be carried out.

Embodiment two:

The heating method of the hypersonic flow field heating device of this embodiment includes the following steps:

The first step, design:

Design conditions: the compressed air is heated to 900K, and the design pressure is 3.5MPa;

Pressure pipeline 1 specification: length 8 meters, specification φ280x14mm, material is S30408 stainless steel;

The electric heating mounting seat 4 and the special-shaped octagonal pad 5 are made of 06Cr19Ni10III stainless steel forgings, and the gap between them and other assembly connection surfaces is less than 0.1mm;

The sealing surface 503 of the special-shaped octagonal gasket 5 refers to the design of metal ring gaskets for steel pipe flanges in HG/T20633-2009;

The electric heating tube material of the electric heater is made of S30408, and the specifications after shrinkage are φ12mm. The internal heating material of the electric heating element is made of high-quality high-temperature resistant and high-resistance alloy wire Ni80Cr20. This material can withstand high temperatures above 900°C as a heating material;

The output power of the first flange and the first matching flange area is 5kW, the output power of the second flange and the second matching flange area is 5kW, the output power of the upper half heating area of the pipeline is 15kW, and the output power of the lower half heating area of the pipeline is 15kW;

The second step, manufacturing:

Manufacture related components of hypersonic flow field heating device according to design standards and drawings;

The third step is to assemble the hypersonic flow field heating device:

Install the electric heating tube 7 and the temperature measuring core 8 on the corresponding position of the electric heating mounting base 4;

Then the electric heating tube 7 and the temperature measuring core 8 are passed through the first U-shaped notch 606 and the second U-shaped notch 608 on the inner flow channel tube 6, and the bolt hole 605 is connected with the inner flow on the installation boss 602. The pipe installation hole 407 is fitted with bolts, and then the electric heating tube 7 and the temperature measurement core 8 are installed on the electric heating tube installation groove 607 and the temperature measurement core installation groove 609;

Put the inner heat insulation layer 9 on the outside of the electric heating tube 7 and the temperature measuring core 8, and at the same time install the gasket 10 on the installation sealing surface 404 of the electric heating mounting seat 4;

Then insert the above-installed components into the pressure-bearing pipeline 1;

The central hole 502 of the special-shaped octagonal gasket body 501 is fitted together with the tapered pipe section 601 of the inner runner pipe 6, and the octagonal sealing surface 503 is sealed and connected with the sealing surface of the second flange 3;

After assembly, the second flange of the device is the air inlet (sliding end), and the first flange is the air outlet (fixed end);

The fourth step, install in the experimental pipeline:

Connect the mating sealing surface 403 of the electrothermal mounting seat 4 of the hypersonic flow field heating device to the first mating flange 13 of the required heating pipeline through the gasket 10, and at the same time, the boss 402 goes deep into the inner hole of the mating first mating flange 13 , then use bolts to fasten the first flange 2 and the first matching flange 13;

Then the special-shaped octagonal gasket 5 is connected to the second matching flange 14 through the octagonal sealing surface 503, and the second flange 3 and the second matching flange 14 are fastened by bolts;

The fifth step, connect the external line:

Connect the external lines of the electric heating tube 7 and the temperature measuring tube 8, connect the external lines of the compensation electric heating tube 11 and the thermocouple 12, install the safety valve on the safety valve installation pipe 506, and install the pressure relief valve on the pressure relief valve installation pipe 507. Pressure relief valve and pressure detection device, connect the above-mentioned lines and detection devices with the control system, use "PLC + power regulator + smart instrument" to control, arrange 8 temperature detection devices on the surface of the 8-meter straight pipeline for temperature monitoring, and realize the temperature Monitoring function, 8 temperature curves are displayed in real time through the touch screen, and 8 temperature history record functions (temperature, time) are displayed and recorded through the touch screen, which can be used for inspection and reference;

The sixth step, parameter setting:

Turn on the hypersonic flow field heating device and control system power supply, and set the heating parameters and temperature and pressure control parameters;

The seventh step, heating and heat preservation:

Start the heating function of the hypersonic flow field heating device. The heating process is divided into two stages for heating. In the first stage, the electric heating tube 7 outputs full power, and the medium temperature of the pressure-bearing pipeline 1 rises rapidly to the set temperature. In the second stage, the electric heating tube 7 The output power is gradually reduced, and the entire system is kept warm. After a period of heat preservation, the surface temperature of the medium in the pipeline and the inner flow channel gradually converge, and the uniformity of the medium temperature in the pressure-bearing pipeline 1 also gradually meets the technical index requirements. Subsequent test operations can be carried out.

By optimizing the structure of the internal pipeline heater, the hypersonic flow field heating device adopts the combination structure of the electric heating mounting seat, the inner runner tube and the special-shaped octagonal pad, and realizes the flow form that does not affect the internal flow field of the heating pipeline while ensuring the heating efficiency , to provide an easy-to-install electric heating device under the condition of high-precision requirements of the flow field, through the heating and temperature measurement of the upper half pipeline and the heating and temperature measurement of the lower half pipeline, to ensure scientific and reasonable heating and temperature control, and provide a Conditions for a stable flow field.

The above description is an explanation of the present invention, not a limitation of the invention. For the limited scope of the present invention, please refer to the claims. Within the protection scope of the present invention, any form of modification can be made.

Claims (8)

1. The hypersonic flow field heating device comprises a pressure-bearing pipeline (1), wherein an insulating layer is arranged outside the pressure-bearing pipeline (1), and the hypersonic flow field heating device is characterized in that: the electric heating device comprises a pressure-bearing pipeline (1), wherein a first flange (2) and a second flange (3) are fixedly arranged at two ends of the pressure-bearing pipeline (1), an electric heating installation seat (4) is arranged at the sealing surface of the first flange (2), a special-shaped octagonal pad (5) is arranged at the sealing surface of the second flange (3), an inner runner pipe (6) is arranged inside the pressure-bearing pipeline (1), one end of the inner runner pipe (6) is fixedly connected with the electric heating installation seat (4), the other end of the inner runner pipe (6) penetrates into the pressure-bearing pipeline (1) and is assembled with the special-shaped octagonal pad (5), an electric heating pipe (7) is arranged outside the inner runner pipe (6), one end of the electric heating pipe (7) is fixedly arranged on the electric heating installation seat (4), one end of the electric heating pipe (7) penetrates out from the outer circumferential surface of the electric heating installation seat (4), a temperature measuring core (8) is fixedly arranged outside the inner runner pipe (6), one end of the temperature measuring core (8) is fixedly arranged on the electric heating installation seat (4), and the outer circumferential surface of the electric heating pipe (8) is concentric with the outer circumferential surface (9) of the electric heating pipe (1); the special-shaped octagonal pad (5) has the structure that: the special-shaped octagonal cushion comprises an annular special-shaped octagonal cushion body (501), wherein a central hole (502) of the special-shaped octagonal cushion body (501) is a conical through hole, two end faces of the special-shaped octagonal cushion body (501) are provided with octagonal sealing faces (503), the circumferential surface of the special-shaped octagonal cushion body (501) is provided with a safety valve mounting hole (504) and a pressure relief hole (505), the safety valve mounting hole (504) is provided with a safety valve mounting pipe (506), and the pressure relief hole (505) is provided with a pressure relief valve mounting pipe (507);

the octagonal sealing surface (503) is of an annular convex structure.

2. The hypersonic flow field heating apparatus as set forth in claim 1, wherein: the structure of the electric heating installation seat (4) is as follows: including annular electric heat mount pad body (401), electric heat mount pad body (401) one side forms boss (402), boss (402) external diameter is less than electric heat mount pad body (401) external circumference diameter, form on the outside electric heat mount pad body (401) body of boss (402) and mate sealed face (403), boss (402) are inside to open there is the toper through-hole that enlarges to boss (402) terminal surface, electric heat mount pad body (401) opposite side forms mounting seal face (404), mounting seal face (404) cooperates with the sealing face of first flange (2), it has annular counter bore to open on mounting seal face (404), annular counter bore with the toper through-hole is concentric, it has a plurality of interior runner pipe mounting holes (407) to open on the bottom surface of annular counter bore, interior runner pipe mounting holes (407) are threaded blind hole, open on the periphery with annular counter bore has a plurality of electric heating pipe outgoing holes (405) and temperature measurement core outgoing hole (406), it has electric heating pipe outgoing holes (408) to have on the electric heating pipe outgoing holes (408), temperature measuring core (8) is installed in temperature measuring core through hole (406) and temperature measuring core through pipe (409).

3. The hypersonic flow field heating apparatus as set forth in claim 1, wherein: the inside of interior runner pipe (6) is cylindrical through-hole, the exterior structure of interior runner pipe (6) includes taper pipe section (601) that one end of interior runner pipe (6) formed, taper pipe section (601) outer wall is to interior runner pipe (6) other end slope, interior runner pipe (6) other end outside forms annular installation boss (602), is installation section (603) with installation boss (602) junction, installation section (603) with be provided with recess section (604) between taper pipe section (601), the external diameter of fluted section (604) is less than or equal to the minimum external diameter of installation section (603) and taper pipe section (601).

4. A hypersonic flow field heating apparatus as set forth in claim 3, wherein: the end face of installation boss (602) is opened there are a plurality of bolt holes (605), bolt holes (605) are along concentric circumference equipartition with interior runner pipe (6), it has a plurality of first U-shaped openings (606) to open on the outer terminal surface of installation boss (602), outer wall that first U-shaped opening (606) passed installation section (603) to form electric heating pipe mounting groove (607) at the outer wall of installation section (603), it has a plurality of second U-shaped openings (608) to open on the outer terminal surface of installation boss (602), second U-shaped opening (608) pass the pipe wall of installation section (603) to form temperature measurement core mounting groove (609) at the outer wall of installation section (603).

5. The hypersonic flow field heating apparatus as set forth in claim 1, wherein: the first flange (2) is connected with the electric heating installation seat (4) through a gasket (10).

6. The hypersonic flow field heating apparatus as set forth in claim 5, wherein: the gasket (10) is an octagonal gasket.

7. The hypersonic flow field heating apparatus as set forth in claim 1, wherein: the outer circumferential surfaces of the first flange (2) and the second flange (3) are fixedly provided with a compensating electric heating pipe (11) and a thermocouple (12).

8. A heating method of a hypersonic flow field heating apparatus as set forth in any one of claims 1 to 7, characterized in that:

the method comprises the following operation steps:

step one, designing:

by designing a structure of matching the hypersonic flow field heating device with a required heating pipeline, such as the length and the thickness of a pressure-bearing pipeline (1), and corresponding first flanges (2), second flanges (3), electric heating installation seats (4), special-shaped octagonal gaskets (5), heating pipes (7) and inner runner pipes (6);

second step, manufacturing:

processing and manufacturing related parts of the hypersonic flow field heating device according to design standards and drawings;

thirdly, assembling a hypersonic flow field heating device:

the electric heating pipe (7) and the temperature measuring core (8) are arranged at the corresponding position of the electric heating installation seat (4);

then, the electric heating pipe (7) and the temperature measuring core (8) penetrate through a first U-shaped opening (606) and a second U-shaped opening (608) which are arranged on the inner runner pipe (6), the bolt holes (605) are matched with inner runner pipe mounting holes (407) which are arranged on the mounting boss (602) through bolts, and then the electric heating pipe (7) and the temperature measuring core (8) are mounted on an electric heating pipe mounting groove (607) and a temperature measuring core mounting groove (609);

the inner heat insulation layer (9) is sleeved outside the electric heating pipe (7) and the temperature measuring core (8), and meanwhile, the gasket (10) is sleeved on the gasket (10) at the mounting sealing surface (404) of the electric heating mounting seat (4);

then the above-mentioned installed components are inserted into the interior of pressure-bearing pipeline (1);

the central hole (502) of the special-shaped octagonal cushion body (501) is matched and sleeved with the taper pipe section (601) of the inner runner pipe (6), and the octagonal sealing surface (503) is in sealing connection with the sealing surface of the second flange (3);

fourth step, install in experimental pipeline:

the paired sealing surfaces (403) of the electric heating installation seat (4) of the hypersonic flow field heating device are connected with the first paired flanges (13) of the heating pipeline to be heated through gaskets (10), meanwhile, the bosses (402) are deeply paired into inner holes of the first paired flanges (13), and then the first flanges (2) and the first paired flanges (13) are fastened by bolts;

then the special-shaped octagonal gasket (5) is connected with the second mating flange (14) through an octagonal sealing surface (503), and the second flange (3) is fastened with the second mating flange (14) through bolts;

fifth step, connecting external circuit:

an external circuit connecting the electric heating pipe (7) and the temperature measuring pipe (8) is connected, an external circuit connecting the compensation electric heating pipe (11) and the thermocouple (12) is connected, a safety valve is arranged on a safety valve installation pipe (506), a pressure release valve and a pressure detection device are arranged on a pressure release valve installation pipe (507), and the circuit and the detection device are connected with a control system;

sixth, parameter setting:

switching on a hypersonic flow field heating device and a control system power supply, and setting a shape-in heating parameter and a temperature and pressure control parameter;

seventh, heating and preserving heat:

starting the heating function of the hypersonic flow field heating device, wherein the heating process is divided into two stages for heating, the medium temperature of the pressure-bearing pipeline (1) is rapidly increased to the set temperature by the full-power output of the electric heating pipe (7) in the first stage, the output power of the electric heating pipe (7) in the second stage is gradually reduced, the whole system is insulated, after a period of insulation, the medium in the pipeline and the surface temperature of the inner runner gradually trend to be the same, the uniformity of the medium temperature in the pressure-bearing pipeline (1) also gradually reaches the technical index requirement, and the subsequent test operation can be performed at the moment.