Method and device for testing internal stress of ice sample under variable temperature environment

Abstract

The utility model provides a kind of ice sample internal stress testing device under variable temperature environment, including fan, the bottom air outlet of fan is equipped with variable temperature cylinder, and variable temperature mechanism is installed in variable temperature cylinder, the end of variable temperature cylinder is fixed with connecting flange, and variable temperature cylinder is connected with flow guide cylinder by connecting flange, and multiple groups of overflow nozzle are penetrated in flow guide cylinder.The ice sample internal stress testing device under variable temperature environment changes the defect that traditional temperature control system is only for the heating of control console internal electrical components, without sample targeted uniform heating structure, can evenly deliver the heat generated by heating wire to the whole sea ice sample through airflow, so that the heat source heat is no longer limited to the electric control cabin area, can effectively adapt to the temperature regulation requirement of ice sample test, avoid the problem of missing dedicated sample temperature control structure in low-temperature environment, and provide stable temperature environment basis for ice sample stress test.

Description

Technical Field

[0001] This invention relates to the field of ice sample internal stress testing devices, specifically an ice sample internal stress testing device under variable temperature conditions. Background Technology

[0002] In recent years, with the development of oil and gas resources and marine transportation in cold regions, the mechanical properties of sea ice have attracted increasing attention. Accurate analysis of the interaction between sea ice and structures is of great significance for the design and safe operation of ice-covered structures.

[0003] Regarding patents for testing equipment for the mechanical properties of sea ice, a search revealed a patent with publication number CN201810723200.8 that discloses a low-temperature resistant portable sea ice tensile and compressive testing machine system. The system includes a pressure sensor 1, a displacement sensor, a pressure head 2, a servo motor 3, and a sea ice sample 5, used to load the sea ice sample. Specifically, the servo motor controls the lifting and lowering of the pressure head to form an axial tensile and compressive load on the sea ice sample. The loading space of the test bench is designed according to the sea ice sample, which greatly reduces the overall weight and volume of the equipment, making it convenient for on-site transportation and movement in ice-covered areas.

[0004] While the aforementioned device can incorporate a temperature control system at the core electrical components, and the temperature sensors within this system can acquire the internal temperature of the control console, automatically activating heat supply to the system when the internal temperature falls below a preset value, ensuring that the internal electrical components operate within the required temperature range unaffected by the low-temperature environment, in actual use, the heat medium generated by the heat source in the temperature control system cannot be evenly distributed on the ice block where stress needs to be tested. The equipment only controls the temperature of the electrical components in the control console, and the heat source only acts on the electrical control compartment, lacking a targeted temperature equalization structure to distribute heat across the entire sea ice sample. The heat medium only makes local contact with the ice block, resulting in significant temperature differences between the sample surface, core, and clamping ends. The mechanical properties of sea ice—tensile strength, compressive strength, elastic modulus, and fracture toughness—are highly sensitive to temperature. Even small temperature differences can lead to variations in mechanical parameters across different areas of the same sample. Temperature interference can also cause tensile and compressive load and stress data to deviate from the intrinsic mechanical properties of sea ice as measured by pressure sensors and deformation curves recorded by displacement sensors, rendering the repeatability and comparability of the test results invalid. Summary of the Invention

[0005] The purpose of this invention is to provide a device for testing the internal stress of ice samples under varying temperature conditions, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, a method for testing the internal stress of ice samples under variable temperature conditions is provided. The method is characterized by: by setting a variable temperature cylinder (2) with a variable temperature mechanism (6) at the bottom air outlet of the fan (1), and combining it with a flow guide cylinder (4) and a heat distribution structure with multiple overflow nozzles (5), the traditional temperature control system has changed the defect of only heating the electrical components inside the control console and lacking a sample-specific uniform temperature heat distribution structure. The heat generated by the heating wire (63) can be evenly transported to the entire area of ​​the sea ice sample through the airflow, so that the heat source is no longer limited to the area of ​​the electrical control chamber. This method can effectively adapt to the temperature control requirements of ice sample testing, avoid the problem of the lack of a dedicated sample temperature control structure under low temperature conditions on site, and provide a stable temperature environment for ice sample stress testing. The specific testing process includes: heating the temperature-changing cylinder to complete the temperature-changing treatment of the airflow, and making the heated airflow uniformly generated and split into jets; that is, after the power supply of the equipment is turned on, the heating wire (63) is powered by the wire (65) to make it heat up, and at the same time the fan (1) is started to output a stable airflow. After the airflow completes the temperature change inside the temperature-changing cylinder (2), it is collected through the guide tube (4) and uniformly sprayed out through multiple sets of overflow nozzles (5) to uniformly control the temperature of the ice sample throughout the entire range. With the help of the testing equipment, the internal stress, deformation, load and other data of the ice sample under the temperature change environment are collected and the mechanical properties are tested.

[0007] The method for testing the internal stress of an ice sample under variable temperature conditions, wherein the variable temperature cylinder is heated: when the equipment is running, the fan (1) starts to generate airflow, and the airflow enters the interior of the variable temperature cylinder (2) arranged concentrically with it from the bottom air outlet. The interior of the variable temperature cylinder (2) is connected to the assembly seat (62) through the dovetail-shaped assembly groove (64) to achieve precise positioning and installation of the alignment frame (61). The annular concentric alignment frame (61) can stably fix the vortex-shaped heating wire (63). The heating wire (63) is powered through the wire (65) so that the heating wire (63) is energized and heated to heat the airflow flowing through the variable temperature cylinder (2).

[0008] The method for testing the internal stress of an ice sample under variable temperature conditions involves the following steps: After heating and temperature adjustment, the airflow flows along the variable temperature cylinder (2) and is guided into the interior of the guide cylinder (4) via the connecting flange (3) at the end. The air inlets of multiple overflow nozzles (5) arranged inside the guide cylinder (4) are connected to the airflow area in the middle of the guide cylinder (4), which can evenly distribute the converged heated airflow. The multiple overflow nozzles (5) arranged at equal intervals vertically spray the distributed warm airflow onto the surface of the ice sample below, allowing the heat generated by the heating wire (63) to cover the ice sample throughout the entire area through the airflow. This replaces the traditional temperature control system's working mode of only controlling the temperature of the electrical components of the control console and only heating the electrical control cabin. This method specifically heats the entire area of ​​the sea ice sample, improves the problem of the heat medium only contacting the ice block locally, reduces the temperature difference between the surface, core, and clamping ends of the ice sample, and reduces the interference of temperature difference on the mechanical performance test data of the ice sample.

[0009] The method for testing internal stress of ice samples under variable temperature conditions, wherein the heating airflow is uniformly generated and split into multiple jets: the heating wire (63) with a vortex structure works in conjunction with multiple sets of overflow nozzles (5) arranged at equal intervals to achieve uniform generation and splitting of the heating airflow, effectively improving the situation where the heat medium only partially contacts the ice sample, reducing the temperature difference between the surface, core and clamping ends of the ice sample, avoiding the difference in mechanical parameters such as tensile strength, compressive strength, elastic modulus and fracture toughness in different areas of the same ice sample caused by small temperature differences, reducing the interference of temperature factors on tensile and compressive loads and stress acquisition data, reducing the deviation of the load curve of the pressure sensor and the deformation curve of the displacement sensor, effectively improving the repeatability and comparability of the test results of the mechanical properties of the ice sample, and ensuring that the test data can conform to the intrinsic mechanical properties of sea ice; First, the assembly groove (64) on the inner wall of the temperature-changing cylinder (2) and the assembly seat (62) on the outer side of the alignment frame (61) are used to complete the assembly and fixation of the temperature-changing mechanism (6). Then, the temperature-changing cylinder (2) and the guide cylinder (4) are firmly connected through the connecting flange (3) to set up and fix the overall structure above the ice sample to be tested.

[0010] The method described uses an ice sample internal stress testing device under variable temperature conditions, which includes a fan (1), a variable temperature cylinder (2) installed at the bottom air outlet of the fan (1), a variable temperature mechanism (6) installed inside the variable temperature cylinder (2), a connecting flange (3) fixed at the end of the variable temperature cylinder (2), and a guide cylinder (4) connected to the variable temperature cylinder (2) through the connecting flange (3). Multiple overflow nozzles (5) are installed inside the guide cylinder (4). The temperature-changing mechanism (6) includes a positioning frame (61) installed inside the temperature-changing cylinder (2), and an electric heating wire (63) is fixed inside the positioning frame (61), with a wire (65) connected to the end of the electric heating wire (63).

[0011] The aforementioned device for testing internal stress of ice samples under variable temperature conditions includes a fan (1) and a variable temperature cylinder (2) arranged in concentric circles, with the air outlet of the fan (1) facing the heating wire (63), and the heating wire (63) and the guide cylinder (4) arranged in opposite directions; the alignment frame (61) is annular, and the alignment frame (61) is concentric within the variable temperature cylinder (2), with the heating wire (63) inside the alignment frame (61) arranged in a spiral structure.

[0012] The aforementioned device for testing the internal stress of an ice sample under variable temperature conditions includes a plurality of assembly seats (62) fixed on the outer circumference of the alignment frame (61), a plurality of assembly slots (64) being opened on the inner wall of the variable temperature cylinder (2), and the sizes of the assembly slots (64) and the assembly seats (62) being compatible, with the assembly seats (62) being inserted into the assembly slots (64); both the assembly slots (64) and the assembly seats (62) are dovetail-shaped structures, and the variable temperature mechanism (6) is positioned and installed in the variable temperature cylinder (2) through the assembly slots (64) and the assembly seats (62).

[0013] The aforementioned device for testing the internal stress of an ice sample under variable temperature conditions includes multiple sets of overflow nozzles (5) equidistantly arranged at the bottom of a guide tube (4), with the air inlet of the overflow nozzles (5) located in the middle of the guide tube (4); the bottom of the multiple sets of overflow nozzles (5) faces the ice sample, and the airflow in the guide tube (4) is diverted through the multiple sets of overflow nozzles (5) and uniformly heated by the heating wire (63). Beneficial effects

[0014] 1. This solution, by installing a temperature-changing cylinder with a temperature-changing mechanism at the bottom air outlet of the fan, combined with a flow guide tube and multiple overflow nozzles to form a heat distribution structure, overcomes the shortcomings of traditional temperature control systems that only heat the electrical components inside the control console and lack a targeted uniform temperature distribution structure for the sample. It can evenly distribute the heat generated by the heating wire to the entire sea ice sample area through airflow, so that the heat source is no longer limited to the electrical control chamber area. It can effectively adapt to the temperature control requirements of ice sample testing, avoid the problem of the lack of a dedicated sample temperature control structure in low-temperature environments, and provide a stable temperature environment for ice sample stress testing.

[0015] 2. This scheme utilizes a vortex-structured heating wire in conjunction with multiple equidistant overflow nozzles to achieve uniform generation and diversion of the heating airflow. This effectively improves the situation where the heat medium only partially contacts the ice sample, reduces the temperature difference between the surface, core, and clamping ends of the ice sample, and avoids differences in tensile and compressive strength, elastic modulus, fracture toughness, and other mechanical parameters caused by small temperature differences in different areas of the same ice sample. It also reduces the interference of temperature factors on tensile and compressive load and stress acquisition data, reduces the deviation of pressure sensor load curves and displacement sensor deformation curves, and effectively improves the repeatability and comparability of ice sample mechanical property test results, ensuring that the test data closely matches the intrinsic mechanical properties of sea ice. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 2 ; Figure 3 For the explosion of this invention Figure 1 ; Figure 4 For the explosion of this invention Figure 2 ; Figure 5 This is a schematic diagram of the guide tube and its connection structure of the present invention; Figure 6 This is a schematic diagram of the overflow nozzle and its connection structure of the present invention; Figure 7 This is a cross-sectional view of the alignment frame and its connection structure of the present invention.

[0017] The following are the labels in the diagram: 1. Fan; 2. Temperature-changing cylinder; 3. Connecting flange; 4. Flow guide cylinder; 5. Overflow nozzle; 6. Temperature-changing mechanism; 61. Alignment frame; 62. Assembly base; 63. Heating wire; 64. Assembly slot; 65. Wire. Detailed Implementation

[0018] The present invention provides a device for testing the internal stress of an ice sample under variable temperature conditions. The device includes a fan 1, a variable temperature cylinder 2 installed at the bottom air outlet of the fan 1, a variable temperature mechanism 6 installed inside the variable temperature cylinder 2, a connecting flange 3 fixed at the end of the variable temperature cylinder 2, and a guide cylinder 4 connected to the variable temperature cylinder 2 through the connecting flange 3. Multiple overflow nozzles 5 are installed through the guide cylinder 4. The temperature-changing mechanism 6 includes an alignment frame 61 installed inside the temperature-changing cylinder 2, and an electric heating wire 63 is fixed inside the alignment frame 61, with a wire 65 connected to the end of the electric heating wire 63.

[0019] In a preferred embodiment, the fan 1 and the temperature-changing cylinder 2 are in a concentric circle structure, and the air outlet of the fan 1 is directly facing the heating wire 63, and the heating wire 63 and the guide cylinder 4 are distributed relative to each other.

[0020] The alignment frame 61 has a ring structure and is concentric within the temperature-changing cylinder 2. The heating wire 63 inside the alignment frame 61 has a spiral structure.

[0021] Multiple sets of mounting seats 62 are fixed on the outer circumference of the alignment frame 61, and multiple sets of mounting slots 64 are opened on the inner wall of the temperature-changing cylinder 2. The dimensions of the mounting slots 64 and the mounting seats 62 are matched, and the mounting seats 62 are inserted into the mounting slots 64.

[0022] Both the assembly slot 64 and the assembly base 62 have a dovetail-shaped structure, and the temperature-changing mechanism 6 is positioned and installed inside the temperature-changing cylinder 2 through the assembly slot 64 and the assembly base 62.

[0023] Multiple overflow nozzles 5 are equidistantly arranged at the bottom of the guide tube 4, and the air inlet of the overflow nozzle 5 is located in the middle of the guide tube 4.

[0024] The bottom of multiple overflow nozzles 5 is directly facing the ice sample, and the airflow in the guide tube 4 is split through multiple overflow nozzles 5, while being uniformly heated by the heating wire 63.

[0025] By installing a temperature-changing cylinder 2 with a temperature-changing mechanism 6 at the bottom air outlet of the fan 1, along with a flow guide cylinder 4 and multiple overflow nozzles 5 to form a heat distribution structure, the shortcomings of traditional temperature control systems that only heat the electrical components inside the control console and lack a targeted uniform temperature distribution structure for the sample are overcome. The heat generated by the heating wire 63 can be evenly distributed to the entire sea ice sample area through airflow, so that the heat source is no longer limited to the electrical control chamber area. This effectively adapts to the temperature control requirements of ice sample testing, avoids the problem of the lack of a dedicated sample temperature control structure in low-temperature environments, and provides a stable temperature environment for ice sample stress testing.

[0026] When the equipment is running, the fan 1 starts to generate airflow. The airflow enters the temperature-changing cylinder 2, which is arranged concentrically with it, from the bottom air outlet. The interior of the temperature-changing cylinder 2 is connected to the mounting base 62 through the dovetail-shaped assembly groove 64, so as to achieve precise positioning and installation of the alignment frame 61. The annular concentric alignment frame 61 can stably fix the spiral heating wire 63. The heating wire 63 is powered through the wire 65, so that the heating wire 63 is energized and heated, thus heating the airflow flowing through the temperature-changing cylinder 2.

[0027] After the airflow undergoes temperature change treatment, the heated and regulated airflow flows along the temperature-changing cylinder 2 and is guided into the guide cylinder 4 through the connecting flange 3 at the end. The air inlets of multiple sets of overflow nozzles 5 arranged inside the guide cylinder 4 are connected to the airflow area in the middle of the guide cylinder 4, which can evenly distribute the converged heated airflow. The multiple sets of equally spaced overflow nozzles 5 vertically spray the distributed warm airflow onto the surface of the ice sample below, so that the heat generated by the heating wire 63 can cover the ice sample throughout the airflow area. This replaces the working mode of the traditional temperature control system that only controls the temperature of the electrical components of the control console and only heats the electrical control chamber.

[0028] This method specifically targets the entire surface of the sea ice sample for heat distribution, improving the problem of the heat medium only partially contacting the ice block, reducing the temperature difference between the surface, core, and clamping ends of the ice sample, and minimizing the interference of temperature difference on the mechanical property test data of the ice sample.

[0029] By cooperating with the vortex-structured heating wire 63 and multiple equidistant overflow nozzles 5, uniform generation and diversion of the heating airflow are achieved. This effectively improves the situation where the heat medium only partially contacts the ice sample, reduces the temperature difference between the surface, core, and clamping ends of the ice sample, avoids differences in mechanical parameters such as tensile strength, compressive strength, elastic modulus, and fracture toughness in different areas of the same ice sample caused by small temperature differences, reduces the interference of temperature factors on tensile and compressive load and stress acquisition data, reduces the deviation of pressure sensor load curves and displacement sensor deformation curves, effectively improves the repeatability and comparability of ice sample mechanical property test results, and ensures that the test data can conform to the intrinsic mechanical properties of sea ice.

[0030] When using the device, the temperature-changing mechanism 6 is first assembled and fixed by the assembly groove 64 on the inner wall of the temperature-changing cylinder 2 and the assembly seat 62 on the outer side of the alignment frame 61. Then, the temperature-changing cylinder 2 and the guide cylinder 4 are firmly connected by the connecting flange 3, and the overall structure is erected and fixed above the ice sample to be tested. During the test, the power supply of the device is turned on, and the heating wire 63 is powered by the wire 65 to make it heat up. At the same time, the fan 1 is started to output a stable airflow. After the airflow is heated and changed in temperature inside the temperature-changing cylinder 2, it is collected by the guide cylinder 4 and sprayed out evenly through multiple sets of overflow nozzles 5 to perform uniform temperature control of the ice sample throughout the entire range. With the help of the testing equipment, the internal stress, deformation, load and other data of the ice sample under the temperature change environment are collected and the mechanical properties are tested.

Claims

1. A method for testing the internal stress of an ice sample under varying temperature conditions, characterized in that: By installing a temperature-changing cylinder (2) with a temperature-changing mechanism (6) at the bottom air outlet of the fan (1), and combining it with a flow guide cylinder (4) and multiple overflow nozzles (5) to form a heat distribution structure, the traditional temperature control system has changed the defect of only heating the electrical components inside the control console and lacking a sample-specific uniform temperature distribution structure. The heat generated by the heating wire (63) can be evenly transported to the entire area of ​​the sea ice sample through the airflow, so that the heat source is no longer limited to the area of ​​the electrical control chamber. It can effectively adapt to the temperature control requirements of ice sample testing, avoid the problem of lack of a dedicated sample temperature control structure in the low temperature environment on site, and provide a stable temperature environment for ice sample stress testing. The specific testing process includes: heating the temperature-changing cylinder to complete the temperature-changing treatment of the airflow, and making the heated airflow uniformly generated and split into jets; that is, after the power supply of the equipment is turned on, the heating wire (63) is powered by the wire (65) to make it heat up, and at the same time the fan (1) is started to output a stable airflow. After the airflow completes the temperature change inside the temperature-changing cylinder (2), it is collected through the guide tube (4) and uniformly sprayed out through multiple sets of overflow nozzles (5) to uniformly control the temperature of the ice sample throughout the entire range. With the help of the testing equipment, the internal stress, deformation, load and other data of the ice sample under the temperature change environment are collected and the mechanical properties are tested.

2. The method for testing the internal stress of an ice sample under varying temperature conditions according to claim 1, characterized in that: The heating of the variable temperature cylinder is as follows: When the equipment is running, the fan (1) starts to generate airflow. The airflow enters the variable temperature cylinder (2) arranged concentrically with it from the bottom air outlet. The variable temperature cylinder (2) is connected to the assembly base (62) through the dovetail-shaped assembly groove (64) to achieve precise positioning and installation of the alignment frame (61). The annular concentric alignment frame (61) can stably fix the vortex-shaped heating wire (63). The heating wire (63) is powered by the wire (65) so that the heating wire (63) is energized and heated to heat the airflow flowing through the variable temperature cylinder (2).

3. A method for testing the internal stress of an ice sample under varying temperature conditions according to claim 1 or 2, characterized in that: The temperature change treatment of the completed airflow: After being heated and regulated, the airflow flows along the temperature change cylinder (2) and is guided into the interior of the guide cylinder (4) through the connecting flange (3) at the end. The air inlets of multiple sets of overflow nozzles (5) arranged inside the guide cylinder (4) are connected to the airflow area in the middle of the guide cylinder (4), which can evenly divide the converged heated airflow. Multiple sets of equally spaced overflow nozzles (5) vertically spray the divided warm airflow onto the surface of the ice sample below, so that the heat generated by the heating wire (63) can cover the ice sample in the entire area through the airflow. This replaces the working mode of the traditional temperature control system that only controls the temperature of the electrical components of the control console and only heats the electrical control cabin. It specifically heats the entire area of ​​the sea ice sample, improves the problem that the heat medium only contacts the ice block locally, reduces the temperature difference between the surface, core and clamping ends of the ice sample, and reduces the interference of temperature difference on the mechanical performance test data of the ice sample.

4. A method for testing the internal stress of an ice sample under varying temperature conditions according to claim 1, 2, or 3, characterized in that: The heating airflow is generated and sprayed evenly: The heating wire (63) with a vortex structure works in conjunction with multiple overflow nozzles (5) arranged at equal intervals to achieve the uniform generation and spraying of the heating airflow. This effectively improves the situation where the heat medium only contacts the ice sample locally, reduces the temperature difference between the surface, core and clamping ends of the ice sample, avoids the difference in mechanical parameters such as tensile strength, compressive strength, elastic modulus and fracture toughness in different areas of the same ice sample caused by small temperature differences, reduces the interference of temperature factors on tensile and compressive loads and stress acquisition data, reduces the deviation of the load curve of the pressure sensor and the deformation curve of the displacement sensor, effectively improves the repeatability and comparability of the test results of the mechanical properties of the ice sample, and ensures that the test data can fit the intrinsic mechanical properties of sea ice. First, the assembly groove (64) on the inner wall of the temperature-changing cylinder (2) and the assembly seat (62) on the outer side of the alignment frame (61) are used to complete the assembly and fixation of the temperature-changing mechanism (6). Then, the temperature-changing cylinder (2) and the guide cylinder (4) are firmly connected through the connecting flange (3) to set up and fix the overall structure above the ice sample to be tested.

5. A device for testing the internal stress of an ice sample under varying temperature conditions using the method described in any one of claims 1-4, characterized in that: Includes a fan (1), a temperature-changing cylinder (2) is installed at the bottom air outlet of the fan (1), and a temperature-changing mechanism (6) is installed inside the temperature-changing cylinder (2). A connecting flange (3) is fixed at the end of the temperature-changing cylinder (2), and a guide cylinder (4) is connected to the temperature-changing cylinder (2) through the connecting flange (3). Multiple overflow nozzles (5) are installed inside the guide cylinder (4). The temperature-changing mechanism (6) includes a positioning frame (61) installed inside the temperature-changing cylinder (2), and an electric heating wire (63) is fixed inside the positioning frame (61), with a wire (65) connected to the end of the electric heating wire (63).

6. The device for testing the internal stress of an ice sample under varying temperature conditions according to claim 5, characterized in that: The fan (1) and the temperature-changing cylinder (2) are in a concentric circle structure, and the air outlet of the fan (1) is directly opposite the heating wire (63), and the heating wire (63) and the guide cylinder (4) are distributed opposite to each other; the alignment frame (61) is in a ring structure, and the alignment frame (61) is in a concentric circle structure inside the temperature-changing cylinder (2), and the heating wire (63) inside the alignment frame (61) is in a vortex structure.

7. A device for testing the internal stress of an ice sample under varying temperature conditions according to claim 5 or 6, characterized in that: Multiple sets of mounting seats (62) are fixed on the outer circumference of the alignment frame (61), and multiple sets of mounting slots (64) are opened on the inner wall of the temperature-changing cylinder (2). The sizes of the mounting slots (64) and the mounting seats (62) are compatible, and the mounting seats (62) are inserted into the mounting slots (64). The mounting slots (64) and the mounting seats (62) are both dovetail-shaped structures, and the temperature-changing mechanism (6) is positioned and installed in the temperature-changing cylinder (2) through the mounting slots (64) and the mounting seats (62).

8. A device for testing the internal stress of an ice sample under varying temperature conditions according to claim 5, 6, or 7, characterized in that: Multiple sets of overflow nozzles (5) are equidistantly arranged at the bottom of the guide tube (4), and the air inlet of the overflow nozzles (5) is located in the middle of the guide tube (4); the bottom of the multiple sets of overflow nozzles (5) faces the ice sample, and the airflow in the guide tube (4) is diverted through the multiple sets of overflow nozzles (5) and uniformly heated by the heating wire (63).

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