An electrically heated plate-shaped fuel simulation body with parallel rectangular channels and a processing method thereof

Abstract

The present invention discloses an electrically heated plate-shaped fuel simulation body of parallel rectangular channels and a processing method thereof, and relates to the field of reactor thermal hydraulic experiment technology. The electrically heated plate-shaped fuel simulation body of parallel rectangular channels comprises a parallel rectangular channel body structure, an inlet end portion connection structure and an outlet end portion connection structure arranged at the inlet and outlet of the parallel rectangular channel body structure. The two closed rectangular channels are processed into an integral form by high-precision laser welding using stainless steel plates, which simplifies the traditional parallel rectangular channel structure; each component effectively solves the technical problems of square-to-circle connection of dissimilar materials, axial expansion under heating, and electrode heating; and a ceramic plate with a narrow slit is used as a thermocouple lead-out channel to achieve the measurement of wall temperature.

Description

Technical Field

[0001] The invention belongs to the technical field of reactor thermal hydraulic experiments, and in particular relates to an electrically heated plate-shaped fuel simulation body test piece with parallel rectangular channels, and a processing method of the simulation body test piece. Background Art

[0002] In response to the needs of reactor miniaturization, high efficiency and high fuel consumption, plate fuel is widely used in advanced research reactors, shipborne reactors and new nuclear power systems due to its compact structure, large heat transfer area and high local heat flux density. The inter-plate spacing of the core using plate fuel is usually very small, and the core coolant flow channel is a narrow rectangular channel. Compared with conventional channels, rectangular channels have better heat transfer performance and have outstanding advantages in enhancing heat transfer and increasing critical heat flux density. However, due to the complexity of its structure, the design and processing of simulation test pieces is a major difficulty.

[0003] In addition, the channels of core coolant are usually closed channels, which are not connected to each other, and parallel channels are formed between different fuel plates. Since the plate spacing is very small, the change of channel gap caused by processing or abnormal working conditions will seriously affect the flow distribution between fuel plates. In extreme cases, it will lead to excessive local heat flux density and the risk of burning fuel plates. Therefore, studying the flow boiling heat transfer characteristics of rectangular channels between plate-shaped fuels and the flow distribution between parallel channels is of great significance for the prediction and design of core thermal hydraulic characteristics.

[0004] In the structural design of the plate-shaped fuel simulation body test piece, it is necessary to overcome key issues such as high temperature and high pressure, sealing and insulation, thermal expansion of the simulation body, and wall temperature measurement. For parallel channels, its structure should be simplified as much as possible while taking into account reliability. In the existing rectangular channel test piece structural design, most of them use bolts to clamp heavy stainless steel plates for pressure, and use ceramics for insulation. The heating method is usually single-sided or opposite-sided heat conduction, which makes its structure complex and the heating efficiency is low. More importantly, this structure cannot effectively realize parallel channels that are closed to each other. Summary of the invention

[0005] In order to solve the difficulties existing in the above-mentioned experimental research, the purpose of the present invention is to provide an electrically heated plate-shaped fuel simulation body test piece with parallel rectangular channels, and to provide a method for processing the same.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] An electrically heated plate-shaped fuel simulation body of parallel rectangular channels, comprising a parallel rectangular channel body structure, an inlet end portion connection structure and an outlet end portion connection structure arranged at the inlet and outlet of the parallel rectangular channel body structure;

[0008] The parallel rectangular channel body structure 7 is an integrated welded structure, consisting of a stainless steel inner plate 13, a stainless steel outer plate 14 and a stainless steel side plate 15, and the stainless steel inner plate 13 is filled with a ceramic plate 16 with a narrow slit; the parallel rectangular channel body structure 7 is formed by laser welding, and the two internal channels surrounded by the stainless steel inner plate 13, the stainless steel outer plate 14 and the stainless steel side plate 15 constitute a parallel rectangular channel; in order to facilitate welding with the inlet end part connection structure and the outlet end part connection structure, the length of the stainless steel outer plate 14 is slightly shorter than the stainless steel inner plate 13 and the stainless steel side plate 15, so that a cavity is left at each end;

[0009] The inlet end connection structure includes an inlet end electrode 1, a braided copper wire 2, a copper transition piece 3, a stainless steel transition piece 4 and an inlet end filling piece 5; wherein one side of the inlet end electrode 1 has a hole, so that one end of the braided copper wire 2 is inserted into the hole and clamped, and a step is left on one side of the hole to prevent the inlet end electrode 1 from slipping; one side of the copper transition piece 3 is processed into a circle, and a circular hole is opened inside, so that the other end of the braided copper wire 2 is inserted into the circular hole and clamped, and the other side of the copper transition piece 3 is processed into a rectangle, and a rectangular hole is opened inside, so that the stainless steel transition piece 4 is inserted into the rectangular hole and welded with silver solder; the material of the stainless steel transition piece 4 is stainless steel, one side is processed into a rectangle, and it matches the rectangular hole of the copper transition piece 3, and a step is processed on the other side of the stainless steel transition piece 4, and the step is placed in the "I"-shaped structure composed of the stainless steel plate inner plate 13 and the stainless steel side plate 15 to ensure that the connection is straight, and then fixed by welding; the cavity near the fluid inlet 6 of the parallel rectangular channel body structure 7 is filled with the inlet end filling piece 5;

[0010] The outlet end connection structure includes an outlet end filling piece 9, a stainless steel connecting piece 10 and an outlet end electrode 11; the stainless steel connecting piece 10 and the outlet end electrode 11 are an integral structure, which is formed by turning, milling and wire cutting processing technology. In the integral structure, one end of the electrode is circular, and one end of the connecting piece is in a "cross" shape. The connection between the two is a step to prevent the outlet end electrode from slipping; a step identical to the stainless steel transition piece 4 is processed at one end of the connecting piece, and the step is placed in the "I"-shaped structure composed of the stainless steel inner plate 13 and the stainless steel side plate 15 to ensure that the connection is straight, and then fixed by welding; the cavity at the fluid outlet 8 of the parallel rectangular channel body structure 7 is filled with the outlet end filling piece 9.

[0011] A thermocouple lead-out hole 18 is provided at the center of the stainless steel connector 10. The thermocouple lead-out hole 18 is a long slot-shaped square hole for leading out a thermocouple wire 12 for measuring the wall temperature. Two round holes are provided on each side of the long slot-shaped square hole, and the deep part of the round holes is opened to form two circulation loops, constituting a cooling water inlet channel 19 and a cooling water outlet channel 20. Cooling water is introduced for cooling during heating to prevent the thermocouple wire 12 from burning due to excessive temperature.

[0012] The internal structure of the outlet electrode 11 is consistent with the internal structure of the stainless steel connecting piece 10 , and is also composed of a thermocouple lead-out hole 18 , a cooling water inlet channel 19 and a cooling water outlet channel 20 .

[0013] The inlet electrode 1 is made of copper rod, and the copper transition piece 3 is made of copper.

[0014] The braided copper wire 2 is made of dense multi-strand soft copper wire, and the length is not less than one tenth of the length of the parallel rectangular channel body structure 7.

[0015] The method for processing the electrically heated plate-shaped fuel simulation body with parallel rectangular channels comprises the following steps:

[0016] Step 1: Determine the length, width and gap size of the parallel rectangular channel, estimate the heat flux density of heating in advance, determine the thickness of the stainless steel plate according to impedance matching, prepare the stainless steel inner plate 13, the stainless steel outer plate 14, the stainless steel side plate 15 and the ceramic plate 16 with a narrow slit, and prepare the aluminum plate for limiting the gap size; wherein the stainless steel inner plate 13 and the stainless steel side plate 15 are of the same length, the stainless steel outer plate 14 is slightly shorter, and a fluid inlet 6 and a fluid outlet 8 consisting of circular small holes are opened on both sides of the stainless steel outer plate 14; the length of the aluminum plate is longer than the length of the stainless steel inner plate 13, and the width is smaller than the width of the parallel rectangular channel, so as to facilitate removal after welding;

[0017] Step 2: Determine the measurement position of the wall temperature of the parallel rectangular channel body structure 7, wherein the lateral position is determined according to the gap 17 on the ceramic plate 16 with a narrow gap, and 5 to 10 axial positions are selected, and are divided into equal intervals according to the total length of the parallel rectangular channel body structure 7; spot weld the thermocouple wire on the inner side of the two stainless steel inner plates 13, attach the ceramic plate 16 with a narrow gap in the middle, clamp it with a clamp, and lead the thermocouple wire 12 from the outlet side along the gap 17 of the ceramic plate; since the thermocouple wire is led out close to the heated wall, in order to prevent the surface insulation layer from burning, a glass fiber sleeve is selected to protect the thermocouple wire;

[0018] Step 3: Weld the stainless steel side plate 15 to the structure in step 2 to form an "I"-shaped structure, wherein laser welding is selected as the welding method to ensure welding strength while preventing the stainless steel plate from deforming, thereby minimizing the impact on the parallel rectangular channel;

[0019] Step 4: Use an aluminum plate with the same size as the narrow gap as a filler, attach a stainless steel outer plate 14 to both sides of the "I"-shaped structure, and weld them by laser welding. Since the stainless steel outer plate 14 is slightly shorter, a cavity will be left on both sides. After welding, take out the filler aluminum plate;

[0020] Step 5: Place the step of the stainless steel transition piece 4 on one side of the structure in step 4, use laser welding, then place the inlet end filler 5 in the cavity, and use laser welding to connect the gap; then connect the copper transition piece 3, the braided copper wire 2 and the inlet end electrode 1 in sequence; silver welding is used between the stainless steel transition piece 4 and the copper transition piece 3; the copper transition piece 3 and the braided copper wire 2 are pressed tightly by a physical method; the braided copper wire 2 and the inlet end electrode 1 are also pressed tightly by a physical method;

[0021] Step 6: Lead the thermocouple wire 12 out from the long slot-shaped square hole of the stainless steel connector 10 and the outlet electrode 11, and make the step of the stainless steel connector 10 overlap the other side of the structure in step 4, use laser welding, and then place the outlet filler 9 in the cavity, and use laser welding to connect the gap.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] 1. Using stainless steel plates and high-precision laser welding, two closed rectangular channels are processed into an integrated structure, which simplifies the traditional parallel rectangular channel structure and is easy to adjust for different sizes.

[0024] 2. The thermocouple wire for measuring the wall temperature is placed inside the two channels and led out from the gap of the ceramic plate and the square hole of the electrode in sequence. At the same time, the ceramic plate can also play a role in bearing pressure. This structure realizes the method of measuring the wall temperature inside the rectangular channel.

[0025] 3. The water-cooled electrode structure ensures that the internal thermocouple wire will not burn out at high temperatures, and also reduces the difficulty of sealing and insulating the external structure; the braided copper wire can effectively absorb the axial thermal expansion of the simulated body when heated; the copper transition piece effectively connects the stainless steel and copper materials together. The above components ensure the reliability of the connection under the simulated body heating conditions.

[0026] The invention provides an electrically heated plate-shaped fuel simulation body with parallel rectangular channels and a processing method of the simulation body, which is of great significance for studying the thermal hydraulic characteristics of the cooling medium in the plate-shaped fuel core. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for the implementation description.

[0028] Figure 1 A schematic diagram of the structure provided for an example of the present invention.

[0029] Figure 2 for Figure 1 AA cross-sectional view, that is, a schematic cross-sectional view of parallel rectangular channels.

[0030] Figure 3 for Figure 1 BB cross-sectional view, i.e., the end face schematic diagram of the stainless steel transition piece.

[0031] Figure 4 for Figure 1 The CC cross-sectional view is a schematic cross-sectional view of a stainless steel connector.

[0032] Figure 5 Schematic diagram of the structure of the ceramic plate. DETAILED DESCRIPTION

[0033] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the present invention.

[0034] like Figure 1 and Figure 2 As shown, the present invention provides an electrically heated plate-shaped fuel simulation body of parallel rectangular channels, which consists of three parts: a parallel rectangular channel body structure, an inlet end portion connection structure and an outlet end portion connection structure arranged at the inlet and outlet of the parallel rectangular channel body structure; wherein the parallel rectangular channel body structure 7 is an integrated welded structure, which consists of a stainless steel inner plate 13, a stainless steel outer plate 14 and a stainless steel side plate 15, and a ceramic plate 16 with a narrow gap is used for filling in the middle. In order to ensure that all stainless steel plates do not deform during the welding process, laser welding is used as the welding process; the two internal channels surrounded by the stainless steel inner plate 13, the stainless steel outer plate 14 and the stainless steel side plate 15 constitute the parallel rectangular channels; in order to facilitate welding with the inlet end portion connection structure and the outlet end portion connection structure, the length of the stainless steel outer plate 14 is slightly shorter than that of the stainless steel inner plate 13 and the stainless steel side plate 15, so that a cavity is left at each end.

[0035] The inlet end connection structure includes an inlet end electrode 1, a braided copper wire 2, a copper transition piece 3, a stainless steel transition piece 4 and an inlet end filling piece 5; wherein a hole is opened on one side of the inlet end electrode 1, so that one end of the braided copper wire 2 is inserted into it and clamped, the diameter of the hole side is 1-2mm larger than the middle part, and a step is left on the hole side to prevent the inlet end electrode from slipping; the copper transition piece 3 is made of red copper, one side is processed into a circle, and a round hole is opened inside, so that the other end of the braided copper wire 2 is inserted into it and clamped, and the other side of the copper transition piece 3 is processed into a rectangle, and a rectangular hole is opened inside, so that the stainless steel transition piece 4 is inserted into it and welded using silver soldering; the stainless steel transition piece 4 is made of stainless steel, one side is processed into a rectangle, and cooperates with the rectangular hole of the copper transition piece 3, and a step is processed on the other side of the stainless steel transition piece 4, and the step is placed in the "I"-shaped structure composed of the stainless steel plate inner plate 13 and the stainless steel side plate 15 to ensure that its connection is straight, and then fixed by welding; the cavity near the fluid inlet 6 of the parallel rectangular channel body structure 7 is filled with the inlet end filling piece 5.

[0036] The outlet end connection structure includes an outlet end filling piece 9, a stainless steel connecting piece 10 and an outlet end electrode 11; the stainless steel connecting piece 10 and the outlet end electrode 11 are an integral structure, which is formed by turning, milling and wire cutting processing technology. In the integral structure, one end of the electrode is circular, and one end of the connecting piece is in a "cross" shape. The connection between the two is a step to prevent the outlet end electrode from slipping; a step identical to the stainless steel transition piece 4 is processed at one end of the connecting piece, and the step is placed in the "I"-shaped structure composed of the stainless steel inner plate 13 and the stainless steel side plate 15 to ensure that the connection is straight, and then fixed by welding; the cavity at the fluid outlet 8 of the parallel rectangular channel body structure 7 is filled with the outlet end filling piece 9.

[0037] Furthermore, the inlet electrode 1 is made of copper rod, and the material of the copper transition piece 3 is copper.

[0038] The braided copper wire 2 is made of dense multi-strand soft copper wire, and the length is not less than one tenth of the length of the parallel rectangular channel body structure 7.

[0039] Figure 3 A schematic diagram of the stainless steel transition piece 4 is shown, that is, the specific structure of the step placed on the parallel rectangular channel body structure 7.

[0040] Figure 4The cross-sectional schematic diagram of the stainless steel connector 10 is shown. A thermocouple lead-out hole 18 is opened in the center of the stainless steel connector 10. The thermocouple lead-out hole 18 is a long slot-shaped square hole for leading out the thermocouple wire 12 for measuring the wall temperature. Two round holes are opened on each side of the long slot-shaped square hole, and the depth of the round holes is opened to form two circulation loops, constituting a cooling water inlet channel 19 and a cooling water outlet channel 20. Cooling water is introduced for cooling during heating to prevent the thermocouple wire 12 from burning due to excessive temperature.

[0041] Furthermore, the internal structure of the outlet electrode 11 is consistent with the internal structure of the stainless steel connector 10 , and is also composed of a thermocouple lead-out hole 18 , a cooling water inlet channel 19 and a cooling water outlet channel 20 .

[0042] Figure 5 It is a schematic diagram of the structure of a ceramic plate 16 with narrow slits.

[0043] Furthermore, in conjunction with the above-mentioned drawings, the processing steps and methods of the electrically heated plate-shaped fuel simulation body with parallel rectangular channels of the present invention are described in detail:

[0044] Step 1: Determine the length, width and gap size of the parallel rectangular channel, estimate the heat flux density of heating in advance, determine the thickness of the stainless steel plate according to impedance matching, prepare the stainless steel inner plate 13, the stainless steel outer plate 14, the stainless steel side plate 15 and the ceramic plate 16 with a narrow slit, and prepare the aluminum plate for limiting the gap size; wherein the stainless steel inner plate 13 and the stainless steel side plate 15 are of the same length, the stainless steel outer plate 14 is slightly shorter, and a fluid inlet 6 and a fluid outlet 8 consisting of circular small holes are opened on both sides of the stainless steel outer plate 14; the length of the aluminum plate is longer than the length of the stainless steel inner plate 13, and the width is smaller than the width of the parallel rectangular channel, so as to facilitate removal after welding;

[0045] Step 2: Determine the measurement position of the wall temperature of the parallel rectangular channel body structure 7, wherein the lateral position is determined according to the gap 17 on the ceramic plate 16 with a narrow gap, and the axial position is selected from 5 to 10, and is divided into equal intervals according to the total length of the parallel rectangular channel body structure 7; spot weld the thermocouple wire on the inner side of the two stainless steel inner plates 13, attach the ceramic plate 16 with a narrow gap in the middle, clamp the three with a clamp, and lead the thermocouple wire 12 from the outlet side along the gap 17 of the ceramic plate; since the thermocouple wire is led out close to the heated wall, in order to prevent the surface insulation layer from burning, a glass fiber sleeve is selected to protect the thermocouple wire;

[0046] Step 3: Weld the stainless steel side plate 15 to the structure in step 2 to form an "I"-shaped structure, wherein laser welding is selected as the welding method, so that the stainless steel plate does not deform while ensuring the welding strength, thereby minimizing the impact on the parallel rectangular channel;

[0047] Step 4: Use an aluminum plate with the same size as the narrow gap as a filler, attach a stainless steel outer plate 14 to both sides of the "I"-shaped structure, and weld them by laser welding. Since the stainless steel outer plate 14 is slightly shorter, a cavity will be left on both sides. After welding, take out the filler aluminum plate;

[0048] Step 5: Place the step of the stainless steel transition piece 4 on one side of the structure in step 4, use laser welding, then place the inlet end filler 5 in the cavity, and use laser welding to connect the gap; then connect the copper transition piece 3, the braided copper wire 2 and the inlet end electrode 1 in sequence; silver welding is used between the stainless steel transition piece 4 and the copper transition piece 3; the copper transition piece 3 and the braided copper wire 2 are pressed tightly by a physical method; the braided copper wire 2 and the inlet end electrode 1 are also pressed tightly by a physical method;

[0049] Step 6: Lead the thermocouple wire 12 out from the long slot-shaped square hole of the stainless steel connector 10 and the outlet electrode 11, and make the step of the stainless steel connector 10 overlap the other side of the structure in step 4, use laser welding, and then place the outlet filler 9 in the cavity, and use laser welding to connect the gap.

[0050] The above is an electrically heated plate-shaped fuel simulation body with parallel rectangular channels and a processing method thereof provided by an embodiment of the present invention.

[0051] The embodiment of the present invention uses a stainless steel plate and processes two closed rectangular channels into an integrated structure through high-precision laser welding, which simplifies the traditional parallel rectangular channel structure and provides a method for measuring the inner wall temperature of the parallel rectangular channel. The present invention has broad application prospects in the field of reactor thermal hydraulic experimental technology and is of great significance for studying the flow heat exchange between core plate-shaped fuels and the flow instability of parallel channels.

[0052] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. An electrically heated plate-shaped fuel simulation body with parallel rectangular channels, characterized in that: It includes a parallel rectangular channel body structure, an inlet end portion connection structure and an outlet end portion connection structure arranged at the inlet and outlet of the parallel rectangular channel body structure; The parallel rectangular channel body structure (7) is an integrated welded structure, consisting of a stainless steel inner plate (13), a stainless steel outer plate (14) and a stainless steel side plate (15), and the stainless steel inner plate (13) is filled with a ceramic plate (16) with a narrow slit; the parallel rectangular channel body structure (7) is formed by laser welding, and the two internal channels surrounded by the stainless steel inner plate (13), the stainless steel outer plate (14) and the stainless steel side plate (15) constitute the parallel rectangular channel; in order to facilitate welding with the inlet end connection structure and the outlet end connection structure, the length of the stainless steel outer plate (14) is slightly shorter than that of the stainless steel inner plate (13) and the stainless steel side plate (15), so that a cavity is left at each end; The inlet end connection structure comprises an inlet end electrode (1), a braided copper wire (2), a copper transition piece (3), a stainless steel transition piece (4) and an inlet end filling piece (5); wherein one side of the inlet end electrode (1) is provided with a hole, so that one end of the braided copper wire (2) is inserted into the hole and clamped, and a step is left on one side of the hole to prevent the inlet end electrode (1) from slipping off; one side of the copper transition piece (3) is processed into a circle, and a circular hole is opened inside, so that the other end of the braided copper wire (2) is inserted into the circular hole and clamped, and the other side of the copper transition piece (3) is processed into a rectangle, and the inner hole is opened. A rectangular hole is provided, so that a stainless steel transition piece (4) is inserted into the rectangular hole and welded using silver soldering; the material of the stainless steel transition piece (4) is stainless steel, one side of which is processed into a rectangle to match the rectangular hole of the copper transition piece (3); a step is processed on the other side of the stainless steel transition piece (4), and the step is placed in an "I"-shaped structure composed of a stainless steel plate inner plate (13) and a stainless steel side plate (15) to ensure that the connection is straight, and then fixed by welding; the cavity near the fluid inlet (6) of the parallel rectangular channel body structure (7) is filled with an inlet end filling piece (5); The outlet end connection structure comprises an outlet end filling piece (9), a stainless steel connecting piece (10) and an outlet end electrode (11); the stainless steel connecting piece (10) and the outlet end electrode (11) are an integral structure formed by turning, milling and wire cutting processing technology; one end of the electrode in the integral structure is circular, and one end of the connecting piece is in a "cross" shape; the connection between the two is a step to prevent the outlet end electrode from slipping; a step identical to the stainless steel transition piece (4) is processed at one end of the connecting piece, and the step is placed in an "I"-shaped structure composed of a stainless steel inner plate (13) and a stainless steel side plate (15) to ensure that the connection is straight, and then fixed by welding; the cavity at the fluid outlet (8) of the parallel rectangular channel body structure (7) is filled with the outlet end filling piece (9).

2. The electrically heated plate-shaped fuel simulation body with parallel rectangular channels according to claim 1, characterized in that: A thermocouple lead-out hole (18) is provided at the center of the stainless steel connector (10). The thermocouple lead-out hole (18) is a square hole in the shape of an elongated groove and is used to lead out a thermocouple wire (12) for measuring the wall temperature. Two circular holes are provided on each side of the square hole in the shape of an elongated groove, and the depth of the circular holes is opened to form two circulation loops, constituting a cooling water inlet channel (19) and a cooling water outlet channel (20). When heating, cooling water is introduced for cooling to prevent the thermocouple wire (12) from being burned due to excessive temperature.

3. The electrically heated plate-shaped fuel simulation body with parallel rectangular channels according to claim 1, characterized in that: The internal structure of the outlet electrode (11) is consistent with the internal structure of the stainless steel connector (10), and is also composed of a thermocouple lead-out hole (18), a cooling water inlet channel (19) and a cooling water outlet channel (20).

4. The electrically heated plate-shaped fuel simulation body with parallel rectangular channels according to claim 1, characterized in that: The inlet end electrode (1) is made of a copper rod, and the material of the copper transition piece (3) is copper.

5. The electrically heated plate-shaped fuel simulation body with parallel rectangular channels according to claim 1, characterized in that: The braided copper wire (2) is made of dense multi-strand soft copper wire, and its length is not less than one tenth of the length of the parallel rectangular channel body structure (7).

6. The method for processing the electrically heated plate-shaped fuel simulation body with parallel rectangular channels according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step 1: Determine the length, width and gap size of the parallel rectangular channel, estimate the heat flux density of heating in advance, determine the thickness of the stainless steel plate according to impedance matching, prepare a stainless steel inner plate (13), a stainless steel outer plate (14), a stainless steel side plate (15) and a ceramic plate (16) with a narrow slit, and prepare an aluminum plate for limiting the gap size; wherein the stainless steel inner plate (13) and the stainless steel side plate (15) are of the same length, the stainless steel outer plate (14) is slightly shorter, and a fluid inlet (6) and a fluid outlet (8) consisting of circular small holes are opened on both sides of the stainless steel outer plate (14); the length of the aluminum plate is longer than the length of the stainless steel inner plate (13), and the width is smaller than the width of the parallel rectangular channel, so as to facilitate removal after welding; Step 2: Determine the measurement position of the wall temperature of the parallel rectangular channel body structure (7), wherein the lateral position is determined according to the gap (17) on the ceramic plate (16) with a narrow gap, and 5 to 10 axial positions are selected and divided into equal intervals according to the total length of the parallel rectangular channel body structure (7); spot weld the thermocouple wire on the inner side of two stainless steel inner plates (13), attach the ceramic plate (16) with a narrow gap in the middle, clamp it with a clamp, and lead the thermocouple wire (12) from the outlet side along the gap (17) of the ceramic plate; since the thermocouple wire is led out close to the heated wall, in order to prevent the surface insulation layer from burning, a glass fiber sleeve is selected to protect the thermocouple wire; Step 3: Weld the stainless steel side plate (15) to the structure in step 2 to form an "I"-shaped structure, wherein laser welding is selected as the welding method to ensure welding strength while preventing the stainless steel plate from deforming, thereby minimizing the impact on the parallel rectangular channels; Step 4: Use an aluminum plate with the same size as the narrow gap as a filler, attach stainless steel outer plates (14) to both sides of the "I"-shaped structure, and weld them by laser welding. Since the stainless steel outer plates (14) are slightly shorter, a cavity will be left on both sides; After welding is completed, the filler aluminum plate is removed; Step 5: Place the step of the stainless steel transition piece (4) on one side of the structure in step 4, use laser welding, then place the inlet end filler (5) in the cavity, and use laser welding to connect the gap; then connect the copper transition piece (3), the braided copper wire (2) and the inlet end electrode (1) in sequence; wherein silver welding is used between the stainless steel transition piece (4) and the copper transition piece (3); the copper transition piece (3) and the braided copper wire (2) are pressed tightly by a physical method; the braided copper wire (2) and the inlet end electrode (1) are also pressed tightly by a physical method; Step 6: Lead the thermocouple wire (12) out from the long slot-shaped square hole of the stainless steel connector (10) and the outlet electrode (11), and make the step of the stainless steel connector (10) overlap the other side of the structure in step 4, use laser welding, and then place the outlet filler (9) in the cavity, and use laser welding to connect the gap.

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