Test method for ice accretion and freezing rain by using high-low temperature test box

Abstract

The invention belongs to the technical field of ice prevention and removal, and relates to a test method for ice accretion and freezing rain by using a high-low temperature test chamber, which comprises the following steps of: constructing a high-low temperature test environment, and describing a test device for ice accretion and freezing rain test by using the high-low temperature test chamber, a principle of the test device and reachable technical indexes; performing a relation test on the water spraying pressure of the water spraying equipment and the icing thickness in a high-low temperature test box; icing tests at different temperatures are carried out in a high and low temperature test box, and different temperature and icing thickness relation tests are set in the high and low temperature test box. The high-low temperature test box simulates subzero temperature, and water spraying equipment is placed in the high-low temperature test box to simulate an icing and freezing rain environment. By setting the temperature of the high and low temperature test box, the number of the nozzles and the water spraying method, the tested product can reach the required icing thickness.

Description

Technical Field

[0001] The invention relates to environmental testing technology, and in particular to a testing method for ice accumulation and freezing rain using a high and low temperature testing chamber. Background Art

[0002] Aircraft anti-icing and de-icing technology is crucial to flight safety. For products exposed to ice accumulation and freezing rain environments, the reliability and functional performance of the products are likely to be damaged. The study of ice accumulation and freezing rain tests using high and low temperature test chambers is to develop a basic ice accumulation and freezing rain test environment at a relatively low economic cost to evaluate the products in advance and improve the reliability of the products. In order to verify the performance indicators of the product in an ice accumulation and freezing rain environment, a test method for ice accumulation and freezing rain using a high and low temperature test chamber was designed. By exploring the effects of the nozzle pressure and number of nozzles of the water spray equipment on the ice thickness of the tested product under different temperature conditions, a complete set of test methods is provided for the ice accumulation and freezing rain tests of new products in high and low temperature test chambers in the future, and a reference basis for the setting of test parameters is provided. Summary of the invention

[0003] The purpose of this invention is to provide a complete set of test methods for the ice accumulation and freezing rain test of new products in high and low temperature test chambers and provide a reference for the setting of test parameters. The effects of nozzle pressure, number of nozzles and water spraying mode of water spraying equipment on the ice thickness of the tested products under different temperature conditions are explored, and a test method for ice accumulation and freezing rain using high and low temperature test chambers is designed.

[0004] The technical solution of the present invention is:

[0005] A method for testing ice accumulation and freezing rain using a high and low temperature test chamber is provided, comprising the following steps:

[0006] Step 1: Build the test environment

[0007] The water storage tank 3, the spray device, and the spray rack support structure 4 are arranged in the high and low temperature test box; the spray device includes a connecting pipe 7, a nozzle 6 and a spray solenoid valve 11; the spray water supply system 1 and the spray air supply system 2 are arranged outside the test box; the connecting pipe 7 passes through the high and low temperature test box to connect the spray device with the water supply system, and a water supply solenoid valve 9 is arranged at the water outlet of the water supply system; the connecting pipe 7 also connects the spray device with the air supply system 2, and an air supply solenoid valve 10 is arranged at the air outlet of the air supply system; the test piece 5 can be tested in the high and low temperature test box; the water storage tank 3 is used to collect water, the spray device is used to form a spray with water supply and air supply, and the spray rack support structure 4 is used to install the test piece; the spray device has a solenoid valve 11 and a nozzle 6; the water storage tank 3 has a drain valve 8 and a drain pipe, and the drain pipe is connected to the outside of the high and low temperature test box;

[0008] Step 2: Clean the test piece and fix it on the spray rack support structure. Place a copper rod with a diameter of Φ25 mm and a height of 60 cm next to the test piece.

[0009] Step 3, open the spray solenoid valve 11, open the air supply solenoid valve 10, and operate the air supply system 2 to supply air to the spray device for purge;

[0010] Step 4: Set the temperature of the high and low temperature test chamber. When the temperature drops to the preset temperature, start timing and maintain this temperature condition for 1 hour.

[0011] Step 5: Close the air supply solenoid valve 10, open the water supply solenoid valve 9, operate the water supply system 1 to supply water to the spray device, and the nozzle 6 evenly sprays the pre-cooled water for 1 hour, so that the water penetrates into the gaps or openings of the test piece, so that the test piece 5 is frozen;

[0012] Step 6: Adjust the temperature in the test chamber to the preset temperature. When the temperature in the test chamber is stable, continue to spray water until the ice accumulated on the surface of the test piece reaches the preset thickness.

[0013] Step 7: Turn off the water supply system 1, close the water supply solenoid valve 9, open the air supply solenoid valve 10, operate the air supply system 2, and perform purging to prevent the nozzle 6 and the pipeline 7 from freezing;

[0014] Step 8, maintain the test temperature of the high and low temperature test chamber to harden the ice;

[0015] Step 9, open the high and low temperature test chamber and measure the ice thickness of the copper rod with a vernier caliper;

[0016] Step 10: Close the high and low temperature test chamber, continue to spray water to increase the thickness of the ice layer on the surface of the test piece, or set the test temperature of the high and low temperature test chamber to 50℃~60℃, and dry the test chamber for 3h;

[0017] Step 11, setting different test temperatures in the high and low temperature test box, changing the number of nozzles or changing the nozzle pressure, repeating the methods of steps 3 to 10, and respectively obtaining the ice accumulation thickness of the measured copper rod.

[0018] Furthermore, the water spraying rate of the water spraying system is 25 mm / h.

[0019] Furthermore, the diameter of the water droplets of the sprayed water is between 1.0 mm and 1.5 mm, and more preferably, 1.1 mm, 1.2 mm, and 1.3 mm are all preferred options.

[0020] Test requirements:

[0021] 1) The high and low temperature test chamber has a low temperature condition below -10°C, which can be adjusted and maintained stable, with a temperature fluctuation of ±1°C;

[0022] 2) The water spraying system has a water spraying rate of 25 mm / h and can ensure uniform spraying on each surface of the specimen;

[0023] 3) The diameter of the water droplets is within the range of 1.0mm to 1.5mm;

[0024] 4) Ability to spray water continuously for more than 1 hour and work at low temperature continuously for more than 4 hours;

[0025] 5) It can drain water effectively.

[0026] The advantages and beneficial effects of the present invention are: the test method of the present invention is comprehensive and includes various working conditions, the test cost is low, the operability is strong, and corresponding data support can be provided for the research and development and improvement of products. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the present invention.

[0028] Among them: spray water supply system 1, spray air supply system 2, water storage tank 3, spray rack support structure 4, test piece 5, nozzle 6, connecting pipe 7, drain valve 8, water supply solenoid valve 9, air supply solenoid valve 10, spray solenoid valve 11. DETAILED DESCRIPTION

[0029] The disclosed examples will be more fully described with reference to the accompanying drawings, in which some (but not all) of the disclosed examples are shown. In fact, many different examples may be described and these examples should not be construed as limited to the examples set forth herein. Instead, these examples are described so that this disclosure will be thorough and complete and will fully convey the scope of the disclosure to those skilled in the art.

[0030] A method for testing ice accumulation and freezing rain using a high and low temperature test chamber is provided, comprising the following steps:

[0031] Step 1: Build the test environment

[0032] The water storage tank 3, the spray device, and the spray rack support structure 4 are arranged in the high and low temperature test box; the spray device includes a connecting pipe 7, a nozzle 6 and a spray solenoid valve 11; the spray water supply system 1 and the spray air supply system 2 are arranged outside the test box; the connecting pipe 7 passes through the high and low temperature test box to connect the spray device with the water supply system, and a water supply solenoid valve 9 is arranged at the water outlet of the water supply system; the connecting pipe 7 also connects the spray device with the air supply system 2, and an air supply solenoid valve 10 is arranged at the air outlet of the air supply system; the test piece 5 can be tested in the high and low temperature test box; the water storage tank 3 is used to collect water, the spray device is used to form a spray with water supply and air supply, and the spray rack support structure 4 is used to install the test piece; the spray device has a solenoid valve 11 and a nozzle 6; the water storage tank 3 has a drain valve 8 and a drain pipe, and the drain pipe is connected to the outside of the high and low temperature test box;

[0033] Step 2: Clean the test piece and fix it on the spray rack support structure. Place a copper rod with a diameter of Φ25 mm and a height of 60 cm next to the test piece.

[0034] Step 3, open the spray solenoid valve 11, open the air supply solenoid valve 10, and operate the air supply system 2 to supply air to the spray device for purge;

[0035] Step 4: Set the temperature of the high and low temperature test chamber. When the temperature drops to the preset temperature, start timing and maintain this temperature condition for 1 hour.

[0036] Step 5: Close the air supply solenoid valve 10, open the water supply solenoid valve 9, operate the water supply system 1 to supply water to the spray device, and the nozzle 6 evenly sprays the pre-cooled water for 1 hour, so that the water penetrates into the gaps or openings of the test piece, so that the test piece 5 is frozen;

[0037] Step 6: Adjust the temperature in the test chamber to the preset temperature. When the temperature in the test chamber is stable, continue to spray water until the ice accumulated on the surface of the test piece reaches the preset thickness.

[0038] Step 7: Turn off the water supply system 1, close the water supply solenoid valve 9, open the air supply solenoid valve 10, operate the air supply system 2, and perform purging to prevent the nozzle 6 and the pipeline 7 from freezing;

[0039] Step 8, maintain the test temperature of the high and low temperature test chamber to harden the ice;

[0040] Step 9, open the high and low temperature test chamber and measure the ice thickness of the copper rod with a vernier caliper;

[0041] Step 10: Close the high and low temperature test chamber, continue to spray water to increase the thickness of the ice layer on the surface of the test piece, or set the test temperature of the high and low temperature test chamber to 50℃~60℃, and dry the test chamber for 3h;

[0042] Step 11, setting different test temperatures in the high and low temperature test box, changing the number of nozzles or changing the nozzle pressure, repeating the methods of steps 3 to 10, and respectively obtaining the ice accumulation thickness of the measured copper rod.

[0043] The water spraying rate of the water spraying system is 25mm / h.

[0044] The diameter of the water droplets sprayed is between 1.0mm and 1.5mm.

[0045] The description of different advantageous arrangements has been presented for purposes of illustration and description, but the description is not intended to be exclusive or limited to examples of the disclosed form. Many modifications and variations will be apparent to those of ordinary skill in the art. Additionally, different advantageous examples may describe different advantages over other advantageous examples. The selected example or examples are chosen and described in order to best illustrate the principles of the examples, the practical application, and to enable those of ordinary skill in the art to understand the disclosure with various examples with various modifications suitable for the particular use contemplated.

Claims

1. A method for testing ice accumulation and freezing rain using a high and low temperature test chamber, characterized in that: The steps include: Step 1: Build the test environment A water storage tank (3), a spray device, and a spray rack support structure (4) are arranged in a high and low temperature test chamber; the spray device comprises a connecting pipe (7), a nozzle (6), and a spray solenoid valve (11); a spray water supply system (1) and a spray air supply system (2) are arranged outside the test chamber; the connecting pipe (7) passes through the high and low temperature test chamber to connect the spray device with the water supply system, and a water supply solenoid valve (9) is arranged at the water outlet of the water supply system; the connecting pipe (7) also connects the spray device with the air supply system (2), and an air supply solenoid valve (10) is arranged at the air outlet of the air supply system; a test piece (5) can be placed in the high and low temperature test chamber; the water storage tank (3) is used to collect water, the spray device is used to form a spray with water supply and air supply, and the spray rack support structure (4) is used to install the test piece; the spray device has a solenoid valve (11) and a nozzle (6); the water storage tank (3) has a drain valve (8) and a drain pipe, and the drain pipe is connected to the outside of the high and low temperature test chamber; Step 2: Clean the test piece and fix it on the spray rack support structure, and place a copper rod next to the test piece; Step 3, open the spray solenoid valve (11), open the air supply solenoid valve (10), and operate the air supply system (2) to supply air to the spray device for purge; Step 4: Set the temperature of the high and low temperature test chamber. When the temperature drops to the preset temperature, start timing and maintain this temperature condition for 1 hour. Step 5: Close the air supply solenoid valve (10), open the water supply solenoid valve (9), operate the water supply system (1) to supply water to the spray device, and spray the pre-cooled water evenly with the nozzle (6) for 1 hour, so that the water penetrates into the gaps or openings of the test piece, so that the test piece (5) is frozen; Step 6: Adjust the temperature in the test chamber to the preset temperature. When the temperature in the test chamber is stable, continue to spray water until the ice accumulated on the surface of the test piece reaches the preset thickness. Step 7: Turn off the water supply system 1, close the water supply solenoid valve (9), open the air supply solenoid valve (10), operate the air supply system (2), and perform purging to prevent the nozzle (6) and the connecting pipe (7) from freezing; Step 8, maintain the test temperature of the high and low temperature test chamber to harden the ice; Step 9, open the high and low temperature test chamber and measure the ice thickness of the copper rod with a vernier caliper; Step 10: Close the high and low temperature test chamber, continue to spray water to increase the thickness of the ice layer on the surface of the test piece, or set the test temperature of the high and low temperature test chamber to 50℃~60℃, and dry the test chamber for 3h; Step 11, setting different test temperatures in the high and low temperature test box, changing the number of nozzles or changing the nozzle pressure, repeating the methods of steps 3 to 10, and respectively obtaining the ice accumulation thickness of the measured copper rod.

2. A transducer excitation circuit for ultrasonic ice detection according to claim 1, characterized in that: The copper rod has a diameter of Φ25 mm.

3. The transducer excitation circuit for ultrasonic ice detection according to claim 1, characterized in that: The length of the copper rod is 60 cm.

4. The transducer excitation circuit for ultrasonic ice detection according to claim 1, characterized in that: The water spraying rate of the water spraying system is 25mm / h.

5. The transducer excitation circuit for ultrasonic ice detection according to claim 1, characterized in that: The diameter of the water droplets sprayed is between 1.0mm and 1.5mm.

6. A transducer excitation circuit for ultrasonic ice detection according to claim 1, characterized in that: The diameter of the water droplets sprayed is 1.1 mm.

7. A transducer excitation circuit for ultrasonic ice detection according to claim 1, characterized in that: The diameter of the water droplets sprayed is 1.2mm.

8. The transducer excitation circuit for ultrasonic ice detection according to claim 1, characterized in that: The diameter of the water droplets sprayed is 1.3mm.

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