A brake emission test air flow adjustment method, system, medium and equipment

Abstract

The present application discloses a brake emission test air flow adjustment method, system, medium and equipment. The method obtains a test cycle condition of a vehicle brake emission test, determines the test cycle condition of the vehicle brake emission test, operates a test vehicle on an actual road according to the test cycle condition and collects a first brake temperature, and then operates the test vehicle on an actual road on a test bench and collects a second brake temperature. The cooling air flow of the brake emission test bench is adjusted by comparing the characteristic value of the first brake temperature with the characteristic value of the second brake temperature to reduce the difference between the temperature characteristic values ​​of the two, thereby achieving consistency between the brake temperature during the bench test and during actual road operation, thereby improving the authenticity and accuracy of the bench test.

Description

Technical Field

[0001] The present application relates to the technical field of vehicle brake emission testing, and in particular to a brake emission testing air flow adjustment method, system, medium and equipment. Background Art

[0002] As the requirements for ecological and environmental protection continue to increase, while the emission of automobile exhaust particulate matter has been reduced, the emission of non-exhaust particulate matter caused by brake and tire wear has become increasingly prominent. According to analysis, the emission of non-exhaust particulate matter caused by automobile brakes, tire wear, etc. currently accounts for 85% of the total emissions in the transportation sector, and brake wear particulate matter dominates the non-exhaust particulate matter. Studies have shown that particulate matter emitted during the braking process contributes 16% to 55% of urban non-exhaust PM10 emissions and 39% to 63% of urban non-exhaust PM2.5 emissions. Therefore, brake wear particulate matter emissions have become the regulatory direction of the next stage of emission standards at home and abroad.

[0003] The number of heavy-duty vehicles in my country only accounts for about 5% of the total number of vehicles, but the non-exhaust particulate matter emissions of each vehicle are more than three times that of light-duty vehicles, and the average annual mileage is about four times that of light-duty vehicles. Based on this, it is estimated that the total amount of non-exhaust particulate matter emitted by heavy-duty vehicles in my country is about 60% of that of light-duty vehicles. Therefore, it is very necessary to regulate the emission of non-exhaust particulate matter from heavy-duty vehicles, especially brake particulate matter. At present, the main automobile brake emission tests include the pin-disc friction device method, brake dynamometer method, chassis dynamometer method and actual road method, among which the brake dynamometer method is the most accurate test method that can guarantee the particle collection efficiency.

[0004] Studies have shown that there is a critical temperature for brake particulate matter emissions, that is, when the temperature of the brake friction surface exceeds a certain value, the amount of brake particulate matter emissions will increase significantly, so brake temperature is an important factor affecting brake emissions. Therefore, in the brake emission test of heavy-duty vehicles based on brake dynamometers, it is necessary to ensure that the brake temperature is consistent with the brake temperature under the actual road operating conditions of heavy-duty vehicles in order to obtain brake emission data close to the actual road operation of heavy-duty vehicles. Therefore, a method is needed to ensure that the brake temperature in the brake dynamometer method is consistent with the brake temperature in actual road operation. Summary of the invention

[0005] In order to solve the above technical problems, the present application is proposed. The embodiments of the present application provide a method, system, medium and device for adjusting air flow in a brake emission test.

[0006] According to one aspect of the present application, a method for adjusting air flow in a brake emission test is provided, comprising: obtaining a test cycle condition of a vehicle brake emission test; wherein the test cycle condition includes a vehicle speed-time curve during the vehicle brake emission test; using a test vehicle to operate in a test site according to the test cycle condition, and collecting a first brake temperature of the test vehicle brake; wherein the ambient temperature of the test site is 23°C±2°C, the ambient humidity is 50%RH±5%RH, and the average ambient wind speed is not greater than 1.5m / s; based on the first brake temperature of the test vehicle brake, calculating the air flow rate of the test vehicle in the test site The method comprises the steps of: obtaining a first temperature characteristic value of the brake under test when the brake under test is operated on the brake emission test bench; driving the brake under test to operate according to the test cycle condition by using a brake emission test bench, and collecting a second brake temperature of the brake under test; calculating a second temperature characteristic value of the brake under test when the brake under test is operated on the brake emission test bench based on the second brake temperature of the brake under test; adjusting a cooling air flow rate of the brake emission test bench based on the first temperature characteristic value and the second temperature characteristic value to reduce a difference between the first temperature characteristic value and the second temperature characteristic value; wherein the cooling air flow rate of the brake emission test bench is used to adjust the second brake temperature of the brake under test.

[0007] In one embodiment, collecting the first brake temperature of the test vehicle brake includes: installing a first thermocouple on the front axle brake of the test vehicle; using the first thermocouple to collect the brake temperature of the front axle brake of the test vehicle during the operation of the test vehicle brake to obtain the first brake temperature; wherein the collection frequency of the first thermocouple is 250HZ, and the first brake temperature includes the brake temperature of the front axle brake of the test vehicle and the corresponding time.

[0008] In one embodiment, collecting the second braking temperature of the brake to be tested includes: installing a second thermocouple on the brake to be tested; using the second thermocouple to collect the braking temperature of the brake to be tested during the operation of the brake emission test bench to obtain the second braking temperature; wherein the collection frequency of the second thermocouple is 250HZ, and the second braking temperature includes the braking temperature of the brake to be tested and the corresponding time.

[0009] In one embodiment, the first temperature characteristic value of the test vehicle when operating in the test site is calculated based on the first braking temperature of the test vehicle brake, including: calculating a first average temperature, a first braking initial temperature average value, and a first braking end temperature average value of the test vehicle during operation based on the first braking temperature; wherein the first average temperature represents the average value of all temperature values ​​of the test vehicle brake during operation, the first braking initial temperature average value represents the average temperature value of the test vehicle brake when all braking events occur during operation, and the first braking end temperature average value represents the average temperature value of the test vehicle brake when all braking events occur during operation.

[0010] In one embodiment, the second temperature characteristic value of the brake under test operating on the brake emission test bench is calculated based on the second braking temperature of the brake under test, including: calculating a second average temperature, a second braking initial temperature average value, and a second braking end temperature average value of the brake under test during the operation of the brake emission test bench based on the second braking temperature; wherein the second average temperature represents the average value of all temperature values ​​of the brake under test during the operation of the brake under test on the brake emission test bench, the second braking initial temperature average value represents the temperature average value of the brake under test when all braking events occur during the operation of the brake under test on the brake emission test bench, and the second braking end temperature average value represents the temperature average value of the brake under test when all braking events end during the operation of the brake under test on the brake emission test bench.

[0011] In one embodiment, adjusting the cooling air flow of the brake emission test bench based on the first temperature characteristic value and the second temperature characteristic value to reduce the difference between the first temperature characteristic value and the second temperature characteristic value includes: calculating a first difference between the first average temperature and the second average temperature, a second difference between the first braking initial temperature average value and the second braking initial temperature average value, and a third difference between the first braking end temperature average value and the second braking end temperature average value; if the first difference is greater than a first temperature threshold, or the second difference is greater than a second temperature threshold, or the third difference is greater than a third temperature threshold, adjusting the cooling air flow of the brake emission test bench to achieve that the first difference is less than or equal to the first temperature threshold, the second difference is less than or equal to the second temperature threshold, and the third difference is less than or equal to the third temperature threshold.

[0012] In one embodiment, the test cycle condition includes multiple acceleration stages and multiple deceleration stages, the multiple acceleration stages are all uniform acceleration stages, and the multiple deceleration stages are all uniform deceleration stages.

[0013] According to another aspect of the present application, a brake emission test air flow adjustment system is provided, including: a test cycle condition acquisition module, used to obtain a test cycle condition of a vehicle brake emission test; wherein the test cycle condition includes a vehicle speed-time curve during the vehicle brake emission test; a site temperature data acquisition module, used to use a test vehicle to operate in a test site according to the test cycle condition, and collect a first brake temperature of the test vehicle brake; wherein the ambient temperature of the test site is 23°C ± 2°C, the ambient humidity is 50% RH ± 5% RH, and the average ambient wind speed is not greater than 1.5 m / s; a site temperature feature calculation module, used to calculate the test vehicle running in the test site based on the first brake temperature of the test vehicle brake. a test bench temperature data acquisition module, used to use the brake emission test bench to drive the brake to be tested to operate according to the test cycle condition, and to collect the second brake temperature of the brake to be tested; a test bench temperature characteristic calculation module, used to calculate the second temperature characteristic value of the brake to be tested running on the brake emission test bench based on the second brake temperature of the brake to be tested; a cooling air flow adjustment module, used to adjust the cooling air flow of the brake emission test bench based on the first temperature characteristic value and the second temperature characteristic value to reduce the difference between the first temperature characteristic value and the second temperature characteristic value; wherein the cooling air flow of the brake emission test bench is used to adjust the second brake temperature of the brake to be tested.

[0014] According to another aspect of the present application, a computer-readable storage medium is provided, wherein the storage medium stores a computer program, and the computer program is used to execute any of the above-mentioned brake emission test air flow adjustment methods.

[0015] According to another aspect of the present application, an electronic device is provided, comprising: a processor; a memory for storing instructions executable by the processor; the processor is used to execute any of the above-mentioned brake emission test air flow adjustment methods.

[0016] The present application provides an air flow adjustment method, system, medium and equipment for brake emission testing, which obtains a test cycle condition of a vehicle brake emission test; wherein the test cycle condition includes a vehicle speed-time curve during the vehicle brake emission test; a test vehicle is operated in a test site according to the test cycle condition, and a first brake temperature of the test vehicle brake is collected; wherein the ambient temperature of the test site is 23°C±2°C, the ambient humidity is 50%RH±5%RH, and the average ambient wind speed is not greater than 1.5m / s; based on the first brake temperature of the test vehicle brake, a first temperature characteristic value of the test vehicle operating in the test site is calculated; a brake emission test bench is used to drive the brake to be tested to operate in accordance with the test cycle condition, and a second brake temperature of the brake to be tested is collected; based on the second brake temperature of the brake to be tested, a temperature characteristic value of the brake to be tested on the brake emission test bench is calculated a second temperature characteristic value of the test bench when the vehicle is under test; based on the first temperature characteristic value and the second temperature characteristic value, adjusting the cooling air flow of the brake emission test bench to reduce the difference between the first temperature characteristic value and the second temperature characteristic value; wherein the cooling air flow of the brake emission test bench is used to adjust the second brake temperature of the brake to be tested; that is, after determining the test cycle condition of the vehicle brake emission test, the test vehicle is operated on the actual road according to the test cycle condition and the first brake temperature is collected, and then the test vehicle is operated on the actual road on the bench and the second brake temperature is collected, and the cooling air flow of the brake emission test bench is adjusted by comparing the characteristic value of the first brake temperature and the characteristic value of the second brake temperature to reduce the difference between the temperature characteristic values ​​of the two, so as to achieve consistency between the brake temperature during the bench test and the actual road operation, thereby improving the authenticity and accuracy of the bench test. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] By describing the embodiments of the present application in more detail in conjunction with the accompanying drawings, the above and other purposes, features and advantages of the present application will become more apparent. The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the accompanying drawings, the same reference numerals generally represent the same components or steps.

[0018] Figure 1 It is a flow chart of a method for adjusting air flow in a brake emission test provided by an exemplary embodiment of the present application.

[0019] Figure 2 It is a schematic diagram of a test cycle operating condition provided by an exemplary embodiment of the present application.

[0020] Figure 3 It is a structural schematic diagram of a brake emission test air flow adjustment device provided by an exemplary embodiment of the present application.

[0021] Figure 4 It is a structural diagram of an electronic device provided by an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0022] Below, the exemplary embodiments according to the present application will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application, and it should be understood that the present application is not limited to the exemplary embodiments described here.

[0023] Figure 1 FIG. 1 is a flow chart of a method for adjusting air flow in a brake emission test provided by an exemplary embodiment of the present application. Figure 1 As shown, the brake emission test air flow adjustment method includes the following steps:

[0024] Step 110: Obtain the test cycle conditions of the vehicle brake emission test.

[0025] The test cycle condition includes the vehicle speed-time curve during the vehicle brake emission test. The test cycle condition is a curve describing the corresponding relationship between the vehicle speed and time during the operation of the vehicle. The test cycle condition in this application can be a transformation of an existing vehicle brake performance test cycle condition (such as a heavy vehicle brake performance test cycle condition) or an exhaust emission test cycle condition, or a newly constructed cycle condition.

[0026] In one embodiment, the test cycle working condition includes multiple acceleration stages and multiple deceleration stages, wherein the multiple acceleration stages are uniform acceleration stages, and the multiple deceleration stages are uniform deceleration stages. The specific working condition is as follows: Figure 2 As shown, the brake emission test bench can easily achieve precise control of the test cycle conditions.

[0027] Step 120: The test vehicle is operated in a test field according to a test cycle condition, and a first brake temperature of a brake of the test vehicle is collected.

[0028] Among them, the ambient temperature of the test site is 23℃±2℃, the ambient humidity is 50%RH±5%RH, and the average wind speed is not more than 1.5m / s. In this application, the driver drives the test vehicle in a closed test site according to the test cycle conditions to collect the brake temperature of the brake of the test vehicle during operation. Among them, the test vehicle should be in good condition, and the brake of the test vehicle should be replaced with a brand new original brake before the test to maximize its test accuracy. And this application limits the ambient temperature, ambient humidity and average wind speed of the test site to obtain the brake temperature that meets the normal environmental conditions. It should be understood that the environmental conditions in this application can be adjusted according to the test requirements. For example, for vehicles that have been running in the north for a long time and vehicles that have been running in the south for a long time, their environmental conditions can be determined according to the environmental conditions of their long-term operating areas. Preferably, the test site in this application is a closed automobile test site, and the road of the test site should be a clean and dry asphalt concrete or concrete pavement.

[0029] Step 130: Based on the first brake temperature of the test vehicle brake, a first temperature characteristic value of the test vehicle running in the test field is calculated.

[0030] After acquiring the first brake temperature of the test vehicle brake, a first temperature characteristic value of the test vehicle when running in the test field is calculated based on the first brake temperature, and the first temperature characteristic value represents the characteristics of the brake temperature of the test vehicle during operation.

[0031] Step 140: Using the brake emission test bench to drive the brake to be tested to operate according to the test cycle condition, and collecting the second brake temperature of the brake to be tested.

[0032] The present application places the brake to be tested (for example, the front axle, middle axle or rear axle to be tested) on a brake emission test bench, uses the brake emission test bench to drive the brake to be tested to operate according to the test cycle conditions, and collects the second brake temperature of the brake to be tested to obtain the brake temperature of the brake during the bench test. It should be understood that at this time, the cooling air flow of the brake emission test bench has an initial value or an adjusted value.

[0033] Step 150: Based on the second brake temperature of the brake to be tested, a second temperature characteristic value of the brake to be tested running on the brake emission test bench is calculated.

[0034] After acquiring the second brake temperature of the brake to be tested on the test bench, a second temperature characteristic value of the brake to be tested when running on the brake emission test bench is calculated based on the second brake temperature. The second temperature characteristic value characterizes the characteristics of the brake temperature during the operation of the brake to be tested on the brake emission test bench.

[0035] Step 160 : Based on the first temperature characteristic value and the second temperature characteristic value, adjust the cooling air flow of the brake emission test bench to reduce the difference between the first temperature characteristic value and the second temperature characteristic value.

[0036] Among them, the cooling air flow of the brake emission test bench is used to adjust the second brake temperature of the brake to be tested. Since there are many brake temperature values ​​during the test process, if a single-point brake temperature value is used to represent the temperature characteristics of the test vehicle when it is running in the test site, this will not only require a large amount of calculation, but also cause a large deviation due to the large amount of data, thereby affecting the adjustment of the cooling air flow. For example, the appropriate cooling air flow may not be obtained. Therefore, the present application represents the brake temperature with the first temperature characteristic value and the second temperature characteristic value, which can improve the calculation efficiency and ensure the test accuracy.

[0037] The present application provides an air flow adjustment method for a brake emission test, which obtains a test cycle condition for a vehicle brake emission test; wherein the test cycle condition includes a vehicle speed-time curve during the vehicle brake emission test; a test vehicle is operated in a test site according to the test cycle condition, and a first brake temperature of the test vehicle brake is collected; wherein the ambient temperature of the test site is 23°C±2°C, the ambient humidity is 50%RH±5%RH, and the ambient average wind speed is not greater than 1.5m / s; based on the first brake temperature of the test vehicle brake, a first temperature characteristic value of the test vehicle operating in the test site is calculated; a brake emission test bench is used to drive the brake to be tested to operate in accordance with the test cycle condition, and a second brake temperature of the brake to be tested is collected; based on the second brake temperature of the brake to be tested, a first brake temperature of the brake to be tested running on the brake emission test bench is calculated a second temperature characteristic value; based on the first temperature characteristic value and the second temperature characteristic value, adjusting the cooling air flow of the brake emission test bench to reduce the difference between the first temperature characteristic value and the second temperature characteristic value; wherein the cooling air flow of the brake emission test bench is used to adjust the second brake temperature of the brake to be tested; that is, after determining the test cycle condition of the vehicle brake emission test, the test vehicle is operated on the actual road according to the test cycle condition and the first brake temperature is collected, and then the test vehicle is operated on the actual road on the bench and the second brake temperature is collected, and the cooling air flow of the brake emission test bench is adjusted by comparing the characteristic value of the first brake temperature with the characteristic value of the second brake temperature to reduce the difference between the temperature characteristic values ​​of the two, so as to achieve consistency between the brake temperature during the bench test and that during the actual road operation, thereby improving the authenticity and accuracy of the bench test.

[0038] In one embodiment, the specific implementation method of the above step 120 may be: installing a first thermocouple on the front axle brake of the test vehicle; using the first thermocouple to collect the brake temperature of the front axle brake of the test vehicle during the operation of the brake of the test vehicle to obtain a first brake temperature; wherein the collection frequency of the first thermocouple is 250HZ, and the first brake temperature includes the brake temperature of the front axle brake of the test vehicle and the corresponding time.

[0039] This application selects a front axle brake (left front axle brake or right front axle brake) and installs a K-type thermocouple in accordance with the requirements of the UN GTR standard (Laboratory Measurement of Brake Emissions for Light-Duty Vehicles, referred to as the UNGTR standard), and detects and records data information such as time, vehicle speed and brake temperature of the front axle brake at a frequency of 250Hz during the operation of the test vehicle.

[0040] In one embodiment, the specific implementation method of the above step 140 may be: installing a second thermocouple on the brake to be tested; using the second thermocouple to collect the brake temperature of the brake to be tested during the operation of the brake emission test bench to obtain a second brake temperature; wherein the collection frequency of the second thermocouple is 250HZ, and the second brake temperature includes the brake temperature of the brake to be tested and the corresponding time.

[0041] Regardless of whether the brake to be tested is the front axle, middle axle or rear axle, this application selects the front axle brake (left front axle brake or right front axle brake) for testing. A K-type thermocouple is installed on the front axle brake in accordance with the UN GTR standard requirements, and during the bench test, the time, vehicle speed, brake temperature of the front axle brake and other data information are detected and recorded at a frequency of 250Hz.

[0042] In one embodiment, the specific implementation method of the above step 130 may be: based on the first braking temperature, calculate the first average temperature of the test vehicle during the operation process, the first braking initial temperature average value, and the first braking end temperature average value; wherein the first average temperature represents the average value of all temperature values ​​of the test vehicle brake during the operation process, the first braking initial temperature average value represents the temperature average value of the test vehicle brake when all braking events occur during the operation process, and the first braking end temperature average value is the temperature average value of the test vehicle brake when all braking events during the operation process of the test vehicle end.

[0043] After collecting the first brake temperature, the average brake temperature ABT1 (°C) of the front axle brake under the test cycle conditions when the test vehicle is running in the test field, as well as the average initial brake temperature IBT1 (°C) and the average final brake temperature FBT1 (°C) of all braking events in the test cycle conditions are calculated based on the first brake temperature.

[0044] In one embodiment, a specific implementation method of the above step 150 may be: based on the second braking temperature, calculating the second average temperature, the second braking initial temperature average value, and the second braking end temperature average value of the brake to be tested during the operation of the brake emission test bench; wherein the second average temperature represents the average value of all temperature values ​​of the brake to be tested during the operation of the brake to be tested on the brake emission test bench, the second braking initial temperature average value represents the temperature average value of the brake to be tested when all braking events occur during the operation of the brake to be tested on the brake emission test bench, and the second braking end temperature average value is the temperature average value of the brake to be tested when all braking events end during the operation of the brake to be tested on the brake emission test bench.

[0045] After collecting the second brake temperature, the average brake temperature ABT2 (°C) of the front axle brake under the test cycle when running on the test bench, as well as the average brake initial temperature IBT2 (°C) and the average brake end temperature FBT2 (°C) of all braking events in the test cycle are calculated based on the second brake temperature.

[0046] In one embodiment, the specific implementation method of the above step 160 can be: calculating a first difference between the first average temperature and the second average temperature, a second difference between the first braking initial temperature average value and the second braking initial temperature average value, and a third difference between the first braking end temperature average value and the second braking end temperature average value; if the first difference is greater than the first temperature threshold, or the second difference is greater than the second temperature threshold, or the third difference is greater than the third temperature threshold, adjusting the cooling air flow of the brake emission test bench to achieve the first difference being less than or equal to the first temperature threshold, the second difference being less than or equal to the second temperature threshold, and the third difference being less than or equal to the third temperature threshold.

[0047] The present application calculates the first difference between the first average temperature and the second average temperature, the second difference between the first braking initial temperature average value and the second braking initial temperature average value, and the third difference between the first braking end temperature average value and the second braking end temperature average value, and determines whether the first difference, the second difference and the third difference meet the preset conditions. If the first difference is greater than the first temperature threshold, or the second difference is greater than the second temperature threshold, or the third difference is greater than the third temperature threshold, the cooling air flow of the brake emission test bench is adjusted until the first difference is less than or equal to the first temperature threshold, the second difference is less than or equal to the second temperature threshold, and the third difference is less than or equal to the third temperature threshold. Specifically, the first temperature threshold is 10°C, the second temperature threshold is 15°C, and the third temperature threshold is 15°C, that is, the adjustment of the cooling air flow is determined to be completed when the following relationship is met:

[0048] |ABT2 - ABT1| ≤ 10℃,

[0049] |IBT2 - IBT1| ≤ 15℃,

[0050] |FBT2 - FBT1| ≤ 15℃.

[0051] In one embodiment, the airflow conditions of brakes of different axles of the same vehicle model during actual road driving are basically the same. Therefore, in the brake emission test, the cooling air flow of other brakes (such as the middle axle brake, the rear axle brake, etc.) of the same vehicle model except the front axle brake adopts the same cooling air flow as the front axle brake.

[0052] Figure 3 FIG. 1 is a schematic diagram of a brake emission test air flow adjustment device provided by an exemplary embodiment of the present application. Figure 3As shown, the brake emission test air flow adjustment system 30 includes: a test cycle condition acquisition module 31, which is used to obtain the test cycle condition of the vehicle brake emission test; wherein the test cycle condition includes a vehicle speed-time curve during the vehicle brake emission test; a site temperature data acquisition module 32, which is used to use the test vehicle to operate in the test site according to the test cycle condition and collect the first brake temperature of the test vehicle brake; wherein the ambient temperature of the test site is 23°C ± 2°C, the ambient humidity is 50%RH ± 5%RH, and the average ambient wind speed is not more than 1.5m / s; a site temperature feature calculation module 33, which is used to calculate the test vehicle running in the test site based on the first brake temperature of the test vehicle brake. a first temperature characteristic value of the brake emission test bench; a test bench temperature data acquisition module 34, used to use the brake emission test bench to drive the brake to be tested to operate according to the test cycle condition, and collect the second brake temperature of the brake to be tested; a test bench temperature characteristic calculation module 35, used to calculate the second temperature characteristic value of the brake to be tested running on the brake emission test bench based on the second brake temperature of the brake to be tested; a cooling air flow adjustment module 36, used to adjust the cooling air flow of the brake emission test bench based on the first temperature characteristic value and the second temperature characteristic value, so as to reduce the difference between the first temperature characteristic value and the second temperature characteristic value; wherein, the cooling air flow of the brake emission test bench is used to adjust the second brake temperature of the brake to be tested.

[0053] The present application provides an air flow adjustment system for a brake emission test, which obtains a test cycle condition of a vehicle brake emission test through a test cycle condition acquisition module 31; wherein the test cycle condition includes a vehicle speed-time curve during the vehicle brake emission test; a site temperature data acquisition module 32 uses a test vehicle to operate in a test site according to the test cycle condition, and collects a first brake temperature of the test vehicle brake; wherein the ambient temperature of the test site is 23°C±2°C, the ambient humidity is 50%RH±5%RH, and the ambient average wind speed is not greater than 1.5m / s; a site temperature characteristic calculation module 33 calculates a first temperature characteristic value of the test vehicle operating in the test site based on the first brake temperature of the test vehicle brake; a bench temperature data acquisition module 34 uses a brake emission test bench to drive the brake to be tested to operate according to the test cycle condition, and collects a second brake temperature of the brake to be tested; a bench temperature characteristic calculation module 35 calculates a first temperature characteristic value of the brake to be tested based on the second brake temperature of the brake to be tested temperature, calculates a second temperature characteristic value of the brake to be tested running on the brake emission test bench; the cooling air flow adjustment module 36 adjusts the cooling air flow of the brake emission test bench based on the first temperature characteristic value and the second temperature characteristic value to reduce the difference between the first temperature characteristic value and the second temperature characteristic value; wherein the cooling air flow of the brake emission test bench is used to adjust the second brake temperature of the brake to be tested; that is, after determining the test cycle condition of the vehicle brake emission test, the test vehicle is operated on the actual road according to the test cycle condition and the first brake temperature is collected, and then the test vehicle is operated on the actual road on the bench and the second brake temperature is collected, and the cooling air flow of the brake emission test bench is adjusted by comparing the characteristic value of the first brake temperature with the characteristic value of the second brake temperature to reduce the difference between the temperature characteristic values ​​of the two, so as to achieve the consistency of the brake temperature during the bench test with that during the actual road operation, thereby improving the authenticity and accuracy of the bench test.

[0054] In one embodiment, the test cycle condition includes multiple acceleration stages and multiple deceleration stages, the multiple acceleration stages are all uniform acceleration stages, and the multiple deceleration stages are all uniform deceleration stages.

[0055] In one embodiment, the site temperature data acquisition module 32 may be further configured as follows: installing a first thermocouple on the front axle brake of the test vehicle; using the first thermocouple to acquire the brake temperature of the front axle brake of the test vehicle during the operation of the brake of the test vehicle to obtain a first brake temperature; wherein the acquisition frequency of the first thermocouple is 250 Hz, and the first brake temperature includes the brake temperature of the front axle brake of the test vehicle and the corresponding time.

[0056] In one embodiment, the above-mentioned test bench temperature data acquisition module 34 can be further configured as follows: installing a second thermocouple on the brake to be tested; using the second thermocouple to collect the brake temperature of the brake to be tested during the operation of the brake emission test bench to obtain a second brake temperature; wherein the collection frequency of the second thermocouple is 250HZ, and the second brake temperature includes the brake temperature of the brake to be tested and the corresponding time.

[0057] In one embodiment, the site temperature characteristic calculation module 33 may be further configured as follows: based on the first braking temperature, calculating a first average temperature of the test vehicle during operation, a first braking initial temperature average value, and a first braking end temperature average value; wherein the first average temperature represents the average value of all temperature values ​​of the test vehicle brake during operation, the first braking initial temperature average value represents the average temperature value of the test vehicle brake when all braking events occur during operation, and the first braking end temperature average value represents the average temperature value of the test vehicle brake when all braking events end during operation.

[0058] In one embodiment, the above-mentioned test bench temperature characteristic calculation module 35 can be further configured to: based on the second braking temperature, calculate the second average temperature, the second braking initial temperature average value, and the second braking end temperature average value of the brake to be tested during the operation of the brake emission test bench; wherein the second average temperature represents the average value of all temperature values ​​of the brake to be tested during the operation of the brake to be tested on the brake emission test bench, the second braking initial temperature average value represents the temperature average value of the brake to be tested when all braking events occur during the operation of the brake to be tested on the brake emission test bench, and the second braking end temperature average value is the temperature average value of the brake to be tested when all braking events end during the operation of the brake to be tested on the brake emission test bench.

[0059] In one embodiment, the cooling air flow adjustment module 36 can be further configured to: calculate a first difference between the first average temperature and the second average temperature, a second difference between the first braking initial temperature average value and the second braking initial temperature average value, and a third difference between the first braking end temperature average value and the second braking end temperature average value; if the first difference is greater than the first temperature threshold, or the second difference is greater than the second temperature threshold, or the third difference is greater than the third temperature threshold, then adjust the cooling air flow of the brake emission test bench to achieve that the first difference is less than or equal to the first temperature threshold, the second difference is less than or equal to the second temperature threshold, and the third difference is less than or equal to the third temperature threshold.

[0060] Below, reference Figure 4The electronic device according to the embodiment of the present application is described. The electronic device may be any one or both of the first device and the second device, or a stand-alone device independent of them, and the stand-alone device may communicate with the first device and the second device to receive the collected input signal from them.

[0061] Figure 4 A block diagram of an electronic device according to an embodiment of the present application is illustrated.

[0062] like Figure 4 As shown, the electronic device 10 includes one or more processors 11 and a memory 12 .

[0063] The processor 11 may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device 10 to perform desired functions.

[0064] The memory 12 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, a random access memory (RAM) and / or a cache memory (cache), etc. The non-volatile memory may include, for example, a read-only memory (ROM), a hard disk, a flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 11 may run the program instructions to implement the methods of the various embodiments of the present application described above and / or other desired functions. Various contents such as input signals, signal components, noise components, etc. may also be stored in the computer-readable storage medium.

[0065] In one example, the electronic device 10 may further include: an input device 13 and an output device 14 , and these components are interconnected via a bus system and / or other forms of connection mechanisms (not shown).

[0066] When the electronic device is a stand-alone device, the input device 13 may be a communication network connector, which is used to receive the collected input signals from the first device and the second device.

[0067] In addition, the input device 13 may also include, for example, a keyboard, a mouse, etc.

[0068] The output device 14 can output various information to the outside, including the determined distance information, direction information, etc. The output device 14 can include, for example, a display, a speaker, a printer, a communication network and a remote output device connected thereto, and the like.

[0069] Of course, to simplify, Figure 4Only some of the components related to the present application in the electronic device 10 are shown, and components such as a bus, an input / output interface, etc. are omitted. In addition, according to specific application situations, the electronic device 10 may also include any other appropriate components.

[0070] In addition to the above-mentioned methods and devices, an embodiment of the present application may also be a computer program product, which includes computer program instructions, which, when executed by a processor, enable the processor to execute the steps of the method according to various embodiments of the present application described in the above-mentioned "Exemplary Method" section of this specification.

[0071] The computer program product may be written in any combination of one or more programming languages ​​to write program codes for performing the operations of the embodiments of the present application, including object-oriented programming languages, such as Java, C++, etc., and conventional procedural programming languages, such as "C" language or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as an independent software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0072] In addition, an embodiment of the present application may also be a computer-readable storage medium on which computer program instructions are stored. When the computer program instructions are executed by a processor, the processor executes the steps of the method according to various embodiments of the present application described in the above "Exemplary Method" section of this specification.

[0073] The computer readable storage medium can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can include, for example, but is not limited to, a system, device or device of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination of the above. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0074] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0075] The block diagrams of the devices, apparatuses, equipment, and systems involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

[0076] It should also be noted that in the apparatus, device and method of the present application, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present application.

[0077] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0078] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A method for adjusting air flow in a brake emission test, characterized in that: include: Acquire a test cycle condition of a vehicle brake emission test; wherein the test cycle condition includes a vehicle speed-time curve during the vehicle brake emission test; The test vehicle is operated in the test site according to the test cycle conditions, and the first brake temperature of the brake of the test vehicle is collected; wherein the ambient temperature of the test site is 23°C ± 2°C, the ambient humidity is 50% RH ± 5% RH, and the average ambient wind speed is not greater than 1.5 m / s; Based on a first brake temperature of the test vehicle brake, a first temperature characteristic value of the test vehicle running in the test site is calculated; Using a brake emission test bench to drive the brake to be tested to operate according to the test cycle working condition, and collecting a second brake temperature of the brake to be tested; Based on a second brake temperature of the brake to be tested, calculating a second temperature characteristic value of the brake to be tested when running on the brake emission test bench; Based on the first temperature characteristic value and the second temperature characteristic value, the cooling air flow of the brake emission test bench is adjusted to reduce the difference between the first temperature characteristic value and the second temperature characteristic value; wherein the cooling air flow of the brake emission test bench is used to adjust the second brake temperature of the brake to be tested.

2. The brake emission test air flow adjustment method according to claim 1, characterized in that: The collecting the first brake temperature of the test vehicle brake comprises: Installing a first thermocouple on the front axle brake of the test vehicle; The first thermocouple is used to collect the brake temperature of the front axle brake of the test vehicle during the operation of the test vehicle brake to obtain the first brake temperature; wherein the collection frequency of the first thermocouple is 250HZ, and the first brake temperature includes the brake temperature of the front axle brake of the test vehicle and the corresponding time.

3. The brake emission test air flow adjustment method according to claim 1, characterized in that: The collecting the second brake temperature of the brake to be tested comprises: Installing a second thermocouple on the brake to be tested; The second thermocouple is used to collect the brake temperature of the brake to be tested during the operation of the brake emission test bench to obtain the second brake temperature; wherein the collection frequency of the second thermocouple is 250HZ, and the second brake temperature includes the brake temperature of the brake to be tested and the corresponding time.

4. The brake emission test air flow adjustment method according to claim 1, characterized in that: The calculating, based on the first brake temperature of the test vehicle brake, of a first temperature characteristic value of the test vehicle running in the test site comprises: Based on the first braking temperature, a first average temperature, a first braking initial temperature average value, and a first braking end temperature average value of the test vehicle during operation are calculated; wherein, the first average temperature represents the average value of all temperature values ​​of the test vehicle's brakes during operation, the first braking initial temperature average value represents the average temperature value of the test vehicle's brakes when all braking events occur during operation, and the first braking end temperature average value is the average temperature value of the test vehicle's brakes when all braking events during operation are completed.

5. The brake emission test air flow adjustment method according to claim 4, characterized in that: The calculating, based on the second brake temperature of the brake to be tested, a second temperature characteristic value of the brake to be tested when running on the brake emission test bench comprises: Based on the second braking temperature, the second average temperature, the second initial braking temperature average value, and the second end braking temperature average value of the brake to be tested during its operation on the brake emission test bench are calculated; wherein, the second average temperature represents the average value of all temperature values ​​of the brake to be tested during its operation on the brake emission test bench, the second initial braking temperature average value represents the temperature average value of the brake to be tested when all braking events occur during its operation on the brake emission test bench, and the second end braking temperature average value is the temperature average value of the brake to be tested when all braking events end during its operation on the brake emission test bench.

6. The brake emission test air flow adjustment method according to claim 5, characterized in that: The adjusting the cooling air flow of the brake emission test bench based on the first temperature characteristic value and the second temperature characteristic value to reduce the difference between the first temperature characteristic value and the second temperature characteristic value includes: Calculating a first difference between the first average temperature and the second average temperature, a second difference between the first braking initial temperature average value and the second braking initial temperature average value, and a third difference between the first braking end temperature average value and the second braking end temperature average value; If the first difference is greater than a first temperature threshold, or the second difference is greater than a second temperature threshold, or the third difference is greater than a third temperature threshold, the cooling air flow of the brake emission test bench is adjusted to achieve that the first difference is less than or equal to the first temperature threshold, the second difference is less than or equal to the second temperature threshold, and the third difference is less than or equal to the third temperature threshold.

7. The brake emission test air flow adjustment method according to claim 1, characterized in that: The test cycle working condition includes multiple acceleration stages and multiple deceleration stages, multiple acceleration stages are all uniform acceleration stages, and multiple deceleration stages are all uniform deceleration stages.

8. A brake emission test air flow adjustment system, characterized in that: include: A test cycle condition acquisition module is used to acquire a test cycle condition of a vehicle brake emission test; wherein the test cycle condition includes a vehicle speed-time curve during the vehicle brake emission test; A site temperature data acquisition module is used to operate the test vehicle in the test site according to the test cycle working condition and collect the first brake temperature of the test vehicle brake; wherein the ambient temperature of the test site is 23°C ± 2°C, the ambient humidity is 50% RH ± 5% RH, and the average ambient wind speed is not more than 1.5 m / s; A site temperature characteristic calculation module, used for calculating a first temperature characteristic value of the test vehicle running in the test site based on a first brake temperature of the test vehicle brake; A test bench temperature data acquisition module, used to drive the brake to be tested to operate according to the test cycle condition using the brake emission test bench, and to collect a second brake temperature of the brake to be tested; a test bench temperature characteristic calculation module, configured to calculate a second temperature characteristic value of the brake to be tested when the brake to be tested is running on the brake emission test bench based on a second brake temperature of the brake to be tested; A cooling air flow adjustment module is used to adjust the cooling air flow of the brake emission test bench based on the first temperature characteristic value and the second temperature characteristic value to reduce the difference between the first temperature characteristic value and the second temperature characteristic value; wherein the cooling air flow of the brake emission test bench is used to adjust the second brake temperature of the brake to be tested.

9. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and the computer program is used to execute the brake emission test air flow adjustment method described in any one of claims 1-7 above.

10. An electronic device, characterized in that: include: processor; a memory for storing instructions executable by the processor; The processor is used to execute the brake emission test air flow adjustment method described in any one of claims 1-7 above.

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