Method for testing ice blockage prevention performance of automobile exhaust silencing system

Abstract

The invention discloses a method for testing ice blockage prevention performance of an automobile exhaust silencing system. The method comprises the following steps: installing a plurality of measurers in an exhaust silencing system to be tested; the exhaust silencing system to be tested is connected with an engine and is arranged at a low temperature; the engine is shut down after running for a first time period, and the reading of each measurer is read after standing for a second time period; comparing the reading of each measurer recorded this time with the reading of each measurer recorded last time, and repeating the last step if the reading of at least one measurer is changed and the operation frequency of the test working condition does not exceed 140; if the readings are not changed or the operation frequency of the test working condition is greater than 140, calculating the ratio of the read of each measurer recorded this time to the height of the exhaust pipeline or the noise reduction cavity at the installation position of the measurer, and when the ratio is less than 0.6, judging that the ice blockage risk is relatively low; when the ratio is larger than or equal to 0.6, it is judged that the ice blockage risk is high. The test method is low in test cost, simple and efficient to operate and reliable in result.

Description

Technical Field

[0001] The present application relates to the technical field of detecting automobile exhaust muffler systems, and in particular, to a method for testing the anti-icing performance of automobile exhaust muffler systems. Background Art

[0002] In winter in cold northern regions, there is a phenomenon that water vapor generated by the combustion of the car engine condenses into the muffler in the exhaust muffler system and accumulates ice, which may cause the exhaust muffler system to be blocked by ice and form an ice blockage problem. At this time, the engine will not be able to start due to the blockage of the exhaust muffler system pipes, and even the user's forced ignition will cause the exhaust muffler system pipes to burst. Although the incidence of ice blockage is not high, it will directly cause the vehicle to fail to start, which has a great impact on the user experience. Therefore, the risk of ice blockage needs to be considered in the development of the exhaust muffler system and ice blockage should be avoided as much as possible. Because the pipes and cavities inside the muffler are numerous and complex, it is not easy to observe, and the icing process is affected by various factors such as driving style, external environment, and ground slope when parking. Therefore, it is not easy to analyze and judge the risk of ice blockage, and it is difficult to reproduce the fault. There is a lack of sufficiently effective ice blockage risk verification methods.

[0003] In the prior art, there are two main testing methods for the anti-icing performance of the exhaust muffler system: one is to infer the ice blocking risk by verifying the ability of the vehicle exhaust muffler system to discharge condensed water. Because the icing process is omitted, the ice blocking risk of the muffler cannot be directly and intuitively reflected. Although the cause of ice blocking is due to the untimely discharge of condensed water, the condensed water discharge ability is not equal to the anti-icing ability. For example, if the condensed water drainage hole of the muffler is not properly located, although the condensed water can be discharged at room temperature, it may not work in cold conditions. The other is to judge the ice blocking risk of the exhaust muffler system by driving the whole vehicle in a cold environment or idling. It is impossible to know the ice condition inside the muffler during the test. The ice blocking risk can only be judged based on the final ice condition. The judgment index is qualitative and there is a possibility of misjudgment. In addition, the above two test methods cannot effectively analyze and reproduce the process of ice blocking from scratch in a specific muffler, and the gradual accumulation of ice and water, and have little guiding effect on the optimization of the exhaust scheme with ice blocking failure. Summary of the invention

[0004] In order to solve at least one aspect of the above problems, the present invention provides a method for testing the anti-icing performance of an automobile exhaust muffler system, comprising the following steps:

[0005] Step 1: Install a measuring device at each bend of the exhaust pipe and each chamber of the muffler package in the exhaust muffler system to be tested to measure the height of the ice surface;

[0006] Step 2: Connect the exhaust muffler system to be tested modified in step 1 to the engine, and place the connected exhaust muffler system to be tested and the engine at a test temperature of -30~-15℃;

[0007] Step 3: Start the engine. If the engine cannot start, the test ends and the ice blockage risk is determined to be high. If the engine can start, proceed to the next step.

[0008] Step 4: After the engine is operated for a first period of time under the test condition, the engine is turned off, and after being left to stand for a second period of time, the reading of each measuring instrument in step 1 is read and recorded;

[0009] Step 5: If the test condition is run 1 times, repeat step 3; if the test condition is run more than 1 times, compare the readings of each measuring instrument recorded this time and last time. If at least one measuring instrument reading has changed and the test condition is run no more than 140 times, repeat step 3; if none of the readings have changed or the test condition is run more than 140 times, calculate the ratio of the reading of each measuring instrument recorded this time to the height of the exhaust pipe or silencer chamber where the measuring instrument is installed. When the ratio is less than 0.6, end the test and determine that the risk of ice blockage is low; when the ratio is greater than or equal to 0.6, end the test and determine that the risk of ice blockage is high.

[0010] Through the above technical scheme, the exhaust muffler system to be tested is simply modified and connected to the engine only, without the need for vehicle testing. The engine is used to simulate the operating conditions in a low-temperature environment, and the icing condition inside the exhaust muffler system is intuitively and quantitatively observed through a measuring instrument, which is conducive to finding the structural risk points that actually cause ice blockage problems in the exhaust muffler system with ice blockage risks. The judgment criteria are relatively clear, and the operation is simple, stable, and controllable. The test results have good control over the key variables of ice blockage, which helps to reduce the interference of the vehicle condition and the external environment on the ice blockage phenomenon, thereby improving the reliability of the test results. The test method of the present application has the advantages of low test cost, simple and efficient operation, and reliable results.

[0011] Taking into account the test duration and freezing speed, preferably, the test temperature is -30~-25°C.

[0012] Taking into account the test efficiency, ice accumulation speed and driving habits, preferably, the test conditions are: after the engine is started, the speed is increased to a maximum steady-state speed of 1000~2000rpm with a transient torque of 36~44Nm, and then the rotation is maintained at a steady-state torque of 9~11Nm.

[0013] Since the first time period is too long or too short, the main effect is to slow down the ice accumulation, that is, the efficiency of the experiment, and it may prolong the experiment time. Preferably, the first time period is 10 to 30 minutes.

[0014] Taking into account the test efficiency and the icing effect, preferably, the second time period is 2 to 4 hours.

[0015] Preferably, the measuring device is a liquid level sensor, and each liquid level sensor is installed on the side wall of each bend in the exhaust pipe of the exhaust muffler system to be tested or on the side wall of each chamber of the muffler package; a display is arranged outside the exhaust muffler system to be tested, and the display is communicatively connected with each liquid level sensor for recording the reading of each liquid level sensor.

[0016] Preferably, the measuring device is a ruler, each ruler is vertically arranged and fixedly connected to the bottom wall of each bend in the exhaust pipe of the exhaust muffler system to be tested or the bottom wall of each chamber of the muffler package; an observation port is opened on the top wall of each bend in the exhaust pipe of the exhaust muffler system to be tested or the top wall of each chamber of the muffler package, and a hole cover is provided on the observation port; when reading, an endoscope is used to read and take pictures.

[0017] Preferably, the observation port is fixedly connected to a connecting tube in communication therewith, and a thread is provided on the outer wall of the connecting tube; a thread is provided on the inner wall of the hole cover, and the hole cover is threadedly connected to the connecting tube, which helps to seal.

[0018] Preferably, the distance between the observation port and the scale is 3 to 5 cm, which facilitates observation.

[0019] The present invention provides a method for testing the anti-icing performance of an automobile exhaust muffler system, which has the following beneficial effects:

[0020] (1) This test method can intuitively and quantitatively observe the icing condition inside the exhaust muffler system by installing measuring instruments at each bend in the exhaust pipe and each chamber of the muffler package in the exhaust muffler system to be tested, which is helpful to find the structural risk points that actually cause ice blockage problems in the exhaust muffler system with ice blockage risks.

[0021] (2) The judgment criteria of this test method are relatively clear, and the operation is simple, stable, and controllable. The test results have good control over the key variables of ice blockage, which helps to reduce the interference of the vehicle condition and external environment on the ice blockage phenomenon, and can draw more reliable conclusions and guiding opinions on the risk of muffler ice blockage.

[0022] (3) In this test method, the modification process is simple and low-cost. There is no need to conduct a full vehicle test. It only needs to be connected to the engine, and the engine can be used to simulate the operating conditions and effectively reproduce the ice blockage failure in the exhaust muffler system to be tested, so that a large amount of effective data can be collected in a short time, which helps to improve test efficiency and reduce costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to better understand the above and other purposes, features, advantages and functions of the present invention, reference may be made to the embodiments shown in the accompanying drawings. The same reference numerals in the accompanying drawings refer to the same components. It should be understood by those skilled in the art that the accompanying drawings are intended to schematically illustrate the preferred embodiments of the present invention and have no limiting effect on the scope of the present invention, and the components in the drawings are not drawn to scale.

[0024] Figure 1 A schematic diagram showing a method for testing the anti-icing performance of an automobile exhaust muffler system according to an embodiment of the present invention;

[0025] Figure 2 A schematic diagram showing the modification position of a method for testing the anti-icing performance of an automobile exhaust muffler system according to an embodiment of the present invention;

[0026] Figure 3 A schematic diagram showing the modification of a method for testing the anti-icing performance of an automobile exhaust muffler system according to an embodiment of the present invention;

[0027] Figure 4 A schematic diagram showing a modification from another angle of a method for testing the anti-icing performance of an automobile exhaust muffler system according to an embodiment of the present invention;

[0028] Figure 5 A schematic diagram of a test condition of a method for testing the anti-icing performance of an automobile exhaust muffler system according to an embodiment of the present invention is shown.

[0029] Description of reference numerals:

[0030] 1. Shell; 2. Hole cover; 3. Connecting tube; 4. Scale. DETAILED DESCRIPTION

[0031] The following is a description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, including various details of the embodiments of the present disclosure to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0032] As used herein, the term "including" and its variations mean open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "based at least in part on". The terms "an example embodiment" and "an embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0033] In order to at least partially solve the above problems and one or more of other potential problems, an embodiment of the present disclosure provides a method for testing the anti-icing performance of an automobile exhaust muffler system, comprising the following steps:

[0034] Step 1: Install a measuring device at each bend of the exhaust pipe and each chamber of the muffler package in the exhaust muffler system to be tested to measure the height of the ice surface;

[0035] Step 2: Connect the exhaust muffler system to be tested modified in step 1 to the engine, and place the connected exhaust muffler system to be tested and the engine at a test temperature of -30~-15℃;

[0036] Step 3: Start the engine. If the engine cannot start, the test ends and the ice blockage risk is determined to be high. If the engine can start, proceed to the next step.

[0037] Step 4: After the engine is operated for a first period of time under the test condition, the engine is turned off, and after being left to stand for a second period of time, the reading of each measuring instrument in step 1 is read and recorded;

[0038] Step 5: If the test condition is run 1 times, repeat step 3; if the test condition is run more than 1 times, compare the readings of each measuring instrument recorded this time and last time. If at least one measuring instrument reading has changed and the test condition is run no more than 140 times, repeat step 3; if none of the readings have changed or the test condition is run more than 140 times, calculate the ratio of the reading of each measuring instrument recorded this time to the height of the exhaust pipe or silencer chamber where the measuring instrument is installed. When the ratio is less than 0.6, end the test and determine that the risk of ice blockage is low; when the ratio is greater than or equal to 0.6, end the test and determine that the risk of ice blockage is high.

[0039] Specifically, Figure 1 As shown, the following steps are included: Step 1: Install a measuring device at each bend of the exhaust pipe and each chamber of the muffler package in the exhaust muffler system to be tested, such as Figure 2 Shown as h1-h9, it is used to measure the height of the ice surface.

[0040] In some embodiments, the measuring device is a liquid level sensor, each of which is installed on the side wall of each bend in the exhaust pipe of the exhaust muffler system to be tested or on the side wall of each chamber of the muffler package; a display is arranged outside the exhaust muffler system to be tested, and the display is communicatively connected with each liquid level sensor for recording the reading of each liquid level sensor.

[0041] In other embodiments, Figure 3 and Figure 4As shown, the measuring device is a scale 4, each scale 4 is vertically arranged and fixedly connected to the bottom wall of the shell 1 at each bend of the exhaust pipe in the exhaust muffler system to be tested or the bottom wall of the shell 1 at each chamber of the muffler package; an observation port is provided on the top wall of the shell 1 at each bend of the exhaust pipe in the exhaust muffler system to be tested or the top wall of the shell 1 at each chamber of the muffler package, and the distance between the observation port and the scale 4 is preferably 3~5cm, and a hole cover 2 is provided on the observation port; when reading, an endoscope is used to read and take pictures. Preferably, a connecting tube 3 connected to it is fixedly connected to the observation port, and a thread is provided on the outer wall of the connecting tube 3; a thread is provided on the inner wall of the hole cover 2, and the hole cover 2 is threadedly connected to the connecting tube 3.

[0042] Step 2: Connect the exhaust muffler system to be tested modified in step 1 to the engine, and place the connected exhaust muffler system to be tested and the engine outdoors or in an environmental chamber at a test temperature of -30 to -15°C. Preferably, the test temperature is -30 to -25°C.

[0043] Step 3: Start the engine. If the engine cannot be started, the test is terminated and the risk of ice blockage is determined to be high. If the engine can be started, proceed to the next step. Considering the test efficiency and user habits, preferably, no preheating is required each time the engine is started.

[0044] Step 4: After the engine is operated for a first period of time under the test condition, the engine is turned off, and after being left to stand for a second period of time, the reading of each measuring device in step 1 is read and recorded; preferably, Figure 5 As shown, the test conditions are: after the engine is started, the speed is increased to a maximum steady-state speed of 1000-2000rpm with a transient torque of 36-44Nm, and then the rotation is maintained at a steady-state torque of 9-11Nm. The first time period is 10-30min, and the second time period is 2-4h. In this embodiment, after the engine is started, the speed is increased to a maximum steady-state speed of 1800rpm with a transient torque of 40Nm, and then the rotation is maintained at a steady-state torque of 10Nm for 20min, and then the engine is turned off and left to stand for 2h. The readings of each measuring instrument after this test are read and recorded.

[0045] Step 5: If the test condition is run 1 times, repeat step 3; if the test condition is run more than 1 times, compare the readings of each measuring instrument recorded this time and last time. If at least one measuring instrument reading has changed and the test condition is run no more than 140 times, repeat step 3; if none of the readings have changed or the test condition is run more than 140 times, calculate the ratio of the reading of each measuring instrument recorded this time to the height of the exhaust pipe or silencer chamber where the measuring instrument is installed. When the ratio is less than 0.6, end the test and determine that the risk of ice blockage is low; when the ratio is greater than or equal to 0.6, end the test and determine that the risk of ice blockage is high.

[0046] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the present invention.

Claims

1. A method for testing the anti-icing performance of an automobile exhaust muffler system, characterized in that: The following steps are involved: Step 1: Install a measuring device at each bend of the exhaust pipe and each chamber of the muffler package in the exhaust muffler system to be tested to measure the height of the ice surface; Step 2: Connect the exhaust muffler system to be tested modified in step 1 to the engine, and place the connected exhaust muffler system to be tested and the engine at a test temperature of -30~-15℃; Step 3: Start the engine. If the engine cannot start, the test is terminated and the ice blockage risk is determined to be high. If it can be started, proceed to the next step; Step 4: After the engine is operated for a first period of time under the test condition, the engine is turned off, and after being left to stand for a second period of time, the reading of each measuring instrument in step 1 is read and recorded; Step 5: If the test condition is run 1 times, repeat step 3; if the test condition is run more than 1 times, compare the readings of each measuring instrument recorded this time and last time. If at least one measuring instrument reading has changed and the test condition is run no more than 140 times, repeat step 3; if none of the readings have changed or the test condition is run more than 140 times, calculate the ratio of the reading of each measuring instrument recorded this time to the height of the exhaust pipe or silencer chamber where the measuring instrument is installed. When the ratio is less than 0.6, end the test and determine that the risk of ice blockage is low; when the ratio is greater than or equal to 0.6, end the test and determine that the risk of ice blockage is high.

2. The method for testing the anti-icing performance of an automobile exhaust muffler system according to claim 1, characterized in that: The test temperature is -30~-25℃.

3. The method for testing the anti-icing performance of an automobile exhaust muffler system according to claim 1, characterized in that: The test condition is: after the engine is started, the speed is increased to a maximum steady-state speed of 1000-2000 rpm with a transient torque of 36-44 Nm, and then the rotation is maintained at a steady-state torque of 9-11 Nm.

4. The method for testing the anti-icing performance of an automobile exhaust muffler system according to claim 1, characterized in that: The first time period is 10 to 30 minutes.

5. The method for testing the anti-icing performance of an automobile exhaust muffler system according to claim 1, characterized in that: The second time period is 2 to 4 hours.

6. The method for testing the anti-icing performance of an automobile exhaust muffler system according to claim 1, characterized in that: The measuring device is a liquid level sensor, each of which is installed on the side wall of each bend of the exhaust pipe in the exhaust muffler system to be tested or on the side wall of each chamber of the muffler package; a display is arranged outside the exhaust muffler system to be tested, and the display is communicatively connected with each liquid level sensor to record the reading of each liquid level sensor.

7. The method for testing the anti-icing performance of an automobile exhaust muffler system according to claim 1, characterized in that: The measuring device is a scale (4), each scale (4) is vertically arranged and fixedly connected to the bottom wall of the shell (1) at each bend of the exhaust pipe in the exhaust muffler system to be tested or the bottom wall of the shell (1) at each chamber of the muffler package; an observation port is opened on the top wall of the shell (1) at each bend of the exhaust pipe in the exhaust muffler system to be tested or the top wall of the shell (1) at each chamber of the muffler package, and a hole cover (2) is arranged on the observation port; when reading, an endoscope is used to read and take pictures.

8. The method for testing the anti-icing performance of an automobile exhaust muffler system according to claim 7, characterized in that: The observation port is fixedly connected to a connecting tube (3) which is in communication therewith, and the outer wall of the connecting tube (3) is provided with a thread; the inner wall of the hole cover (2) is provided with a thread, and the hole cover (2) is threadedly connected to the connecting tube (3).

9. The method for testing the anti-icing performance of an automobile exhaust muffler system according to claim 7, characterized in that: The distance between the observation port and the scale (4) is 3 to 5 cm.

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