CN203148872U - Forced-convection heat transfer experimental apparatus outside tube - Google Patents

Abstract

The utility model discloses a forced-convection heat transfer experimental apparatus outside a tube. The forced-convection heat transfer experimental apparatus outside the tube comprises a ventilating tube, a first test tube, an experimental tube, a second test tube, a shrinkage tube, a speed measuring tube, an expansion tube and a centrifugal induced draught fan, wherein the ventilating tube is provided with a horn-shaped inlet; the first test tube is connected with the ventilating tube; the experimental tube is connected with the first test tube; the second test tube is connected with the experimental tube; the shrinkage tube is connected with the second test tube; the speed measuring tube is connected with the shrinkage tube; the expansion tube is connected with the speed measuring tube; the centrifugal induced draught fan is connected with the expansion tube; a lattice structure is arranged in the ventilating tube; a steady-flow filter screen is arranged between the ventilating tube and the first test tube; an inlet temperature measuring meter is arranged in the first test tube; a heating tube is arranged on the experimental tube; an outlet temperature measuring meter is arranged on the second test tube; an air taking tube is arranged in the speed measuring tube; and the air taking tube is connected with an external micro pressure meter. The forced-convection heat transfer experimental apparatus outside the tube is simple in structure, low in manufacturing and maintaining costs, good in experimental airflow stability, good in turbulence level, capable of effectively improving the test precision, and convenient for well understanding experimental principles.

Description

Experimental device for forced convection heat transfer outside the tube

technical field

The utility model belongs to the field of convective heat transfer experiments outside the tube, in particular to an experimental device for forced convective heat transfer outside the tube.

Background technique

There are some deficiencies in the existing experimental equipment for convective heat transfer outside the tube, such as large functional limitations, generally only 1 to 2 experimental tasks can be completed, and the experimental airflow stability is poor, and the degree of turbulence is also large. The ground area is also larger, and the structure is also more complicated, and it is inconvenient to maintain and manage, and the practicability is poor. .

Contents of the invention

The purpose of this utility model is to provide an experimental device for forced convection heat transfer outside the tube with simple structure, good stability of experimental airflow and good turbulence.

The technical solution to realize the purpose of this utility model is: a forced convection heat exchange experiment device outside the tube, comprising a vent pipe with a trumpet-shaped inlet, a first test tube connected to the output end of the vent pipe, and the first test tube connected to the first test tube. A test tube connected to the output end of the test tube, a second test tube connected to the output end of the test tube, a shrink tube connected to the output end of the second test tube, and a shrink tube connected to the output end of the shrink tube The velocity measuring tube, the expansion tube connected to the output end of the velocity measuring tube, the centrifugal induced draft fan connected to the output end of the expansion tube, a grid structure is arranged in the ventilation tube, and the ventilation tube and the first A steady flow filter is provided between the test tubes, an inlet temperature gauge is provided in the first test tube, a heating tube is provided on the test tube, and an outlet temperature gauge is provided on the second test tube , an air-taking pipe is arranged in the speed-measuring tube, and the air-taking pipe is connected with an external micromanometer.

It also includes a heating pipe control driving device, a control computer connected with the heating pipe control driving device, and the heating pipe control driving device is connected with the heating pipe.

The lower end of the centrifugal induced draft fan is provided with an air volume regulating gate.

The micromanometer is an inclined micromanometer.

Its working principle is briefly described as follows: Driven by the centrifugal fan, the experimental airflow enters from the horn-shaped inlet, and the experimental airflow passes through the ventilation pipe, the first test pipe, the experimental pipe, the second test pipe, the shrinkage pipe, the speed measurement and the expansion pipe in turn. The air duct adopts a trumpet-shaped inlet setting, so that the experimental air can enter smoothly, which reduces the air resistance and air turbulence to a certain extent. There is a grid warp structure in the ventilation pipe, which can break up the experimental air flow to reduce the incoming flow. The degree of turbulence provides the basis for the uniformity of the experimental airflow in the next step, and then passes through the steady flow filter. Since the steady flow filter is a regular sieve-like structure, its aperture is much smaller than the grid diameter, which can further disperse the airflow and break the airflow. The turbulence of the experimental airflow is uniform, and an inlet temperature measuring instrument is placed in the first test tube to measure the temperature of the experimental airflow before the heat exchange occurs. A heat pipe is installed on the test pipe to make the experimental airflow convect with the heat pipe. Heat exchange, after the heat exchange, the temperature of the experimental airflow rises and enters the second test tube. The temperature at this time is detected by the outlet temperature gauge, and then the experimental airflow enters the shrink tube, so that the experimental airflow can be depressurized and accelerated, and enters the speed measuring tube. The flow rate of the experimental airflow is detected by the air pipe and the micromanometer, and then enters the expansion pipe to realize the pressurization and deceleration of the experimental airflow. Since the outlet of the expansion pipe is connected to the centrifugal induced draft fan, the air flow is adjusted by the air volume after passing through the induced draft fan. The gate is discharged into the atmosphere; the inclined micromanometer is connected with the air pipe, and its function is to display the velocity value measured by the speed measuring tube; the heating pipe control drive device is connected with the heat pipe, and the temperature value of the heat pipe is realized by the thermocouple arranged on the surface of the heat pipe. Measurement, heat pipe heating power control and other functions; the control computer is connected with the heat pipe control drive device, and the computer is used for the collection and processing of experimental data.

The utility model has positive effects: The utility model has a simple structure, low manufacturing and maintenance costs, easy disassembly and integrated assembly of various components, good stability of the experimental airflow and good turbulence, and effectively improves the accuracy of the test , to facilitate a better understanding of the experimental principle.

Description of drawings

In order to make the content of the utility model easier to understand clearly, the utility model will be further described in detail according to specific embodiments below in conjunction with the accompanying drawings, wherein:

Fig. 1 is the structural representation of the utility model.

Detailed ways

(Example 1)

Fig. 1 shows a specific embodiment of the utility model, wherein Fig. 1 is a structural schematic diagram of the utility model.

See Fig. 1, a kind of forced convection heat transfer experiment device outside the tube, comprising a ventilation pipe 2 with a trumpet-shaped inlet 1, a first test tube 3 connected to the output end of the ventilation pipe 2, and the first test tube 3 connected to the output end of the ventilation pipe 2. The experimental tube 4 connected to the output end of the tube 3, the second test tube 5 connected to the output end of the experimental tube 4, the shrink tube 6 connected to the output end of the second test tube 5, and the shrink tube 6 The velocity measuring tube 7 connected to the output end, the expansion tube 8 connected to the output end of the velocity measuring tube 7, the centrifugal induced draft fan 9 connected to the output end of the expansion tube 8, and a grid is arranged in the ventilation pipe 2 Structure 10, a steady flow filter screen 11 is provided between the ventilation pipe 2 and the first test pipe 3, an inlet temperature measuring gauge 12 is provided in the first test pipe 3, and an inlet temperature measuring gauge 12 is provided in the test pipe 4. A heating pipe 13 is arranged on the top, an outlet temperature measuring gauge 14 is arranged on the second test pipe 5, an air-taking pipe 15 is arranged in the speed-measuring pipe 7, and the air-taking pipe 15 and the external micromanometer 16 connected.

It also includes a heating pipe control driving device 17 , a control computer 18 connected with the heating pipe control driving device 17 , and the heating pipe control driving device 17 is connected with the heating pipe 13 .

An air volume regulating gate 19 is provided at the lower end of the centrifugal induced draft fan 9 .

The micromanometer 16 is an inclined micromanometer.

Its working principle is briefly described as follows: Driven by the centrifugal fan, the experimental airflow enters from the horn-shaped inlet, and the experimental airflow passes through the ventilation pipe, the first test pipe, the experimental pipe, the second test pipe, the shrinkage pipe, the speed measurement and the expansion pipe in turn. The air duct adopts a trumpet-shaped inlet setting, so that the experimental air can enter smoothly, which reduces the air resistance and air turbulence to a certain extent. There is a grid warp structure in the ventilation pipe, which can break up the experimental air flow to reduce the incoming flow. The degree of turbulence provides the basis for the uniformity of the experimental airflow in the next step, and then passes through the steady flow filter. Since the steady flow filter is a regular sieve-like structure, its aperture is much smaller than the grid diameter, which can further disperse the airflow and break the airflow. The turbulence of the experimental airflow is uniform, and an inlet temperature measuring instrument is placed in the first test tube to measure the temperature of the experimental airflow before the heat exchange occurs. A heat pipe is installed on the test pipe to make the experimental airflow convect with the heat pipe. Heat exchange, after the heat exchange, the temperature of the experimental airflow rises and enters the second test tube. The temperature at this time is detected by the outlet temperature gauge, and then the experimental airflow enters the shrink tube, so that the experimental airflow can be depressurized and accelerated, and enters the speed measuring tube. The flow rate of the experimental airflow is detected by the air pipe and the micromanometer, and then enters the expansion pipe to realize the pressurization and deceleration of the experimental airflow. Since the outlet of the expansion pipe is connected to the centrifugal induced draft fan, the air flow is adjusted by the air volume after passing through the induced draft fan. The gate is discharged into the atmosphere; the inclined micromanometer is connected with the air pipe, and its function is to display the velocity value measured by the speed measuring tube; the heating pipe control drive device is connected with the heat pipe, and the temperature value of the heat pipe is realized by the thermocouple arranged on the surface of the heat pipe. Measurement, heat pipe heating power control and other functions; the control computer is connected with the heat pipe control drive device, and the computer is used for the collection and processing of experimental data.

Apparently, the above-mentioned embodiments of the present utility model are only examples for clearly illustrating the present utility model, rather than limiting the implementation manner of the present utility model. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. It is not necessary and impossible to exhaustively list all the implementation manners here. And these obvious changes or changes derived from the essential spirit of the present utility model still belong to the protection scope of the present utility model.

Claims (4)

1. A forced convection heat transfer experimental device outside a tube, comprising a vent pipe with a trumpet-shaped inlet, a first test tube connected to the output end of the vent pipe, and a first test tube connected to the output end of the first test tube. Experimental tube, a second test tube connected to the output end of the experimental tube, a shrink tube connected to the output end of the second test tube, a speed measuring tube connected to the output end of the shrink tube, and the speed measuring tube The expansion pipe connected to the output end, and the centrifugal induced draft fan connected to the output end of the expansion pipe are characterized in that: a grid structure is provided in the ventilation pipe, and a grid structure is arranged between the ventilation pipe and the first test pipe. A steady flow filter screen is provided, an inlet temperature measuring gauge is arranged in the first test tube, a heating tube is arranged on the experiment tube, an outlet temperature measuring gauge is arranged on the second test tube, An air-taking pipe is arranged inside the velocity-measuring pipe, and the air-taking pipe is connected with an external micromanometer. 2. The experimental device for forced convection heat exchange outside the tube according to claim 1, characterized in that: it also includes a heating tube control drive device, a control computer connected with the heating tube control drive device, and the heating tube control drive The device is connected with the heat pipe. 3. The experimental device for forced convection heat exchange outside the tube according to claim 2, characterized in that: an air volume regulating gate is provided at the lower end of the centrifugal induced draft fan. 4. The external forced convection heat transfer experimental device according to claim 3, characterized in that: the micromanometer is an inclined micromanometer.

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