Comprehensive test system and method for clothing radiation and convection heat dissipation mechanism research

Abstract

The invention discloses a comprehensive test system and method for clothing radiation and convection heat dissipation mechanism research, and belongs to the technical field of clothing thermal performance tests.The comprehensive test system comprises a thermal dummy model, an environment control module, a data acquisition module and a signal processing module, and the thermal dummy model simulates human physiological characteristics according to requirements to adjust the body surface temperature; the partitioned thermal control units are used for independently controlling the temperature of a trunk and four limbs; the environment control module comprises a wind tunnel system and a temperature and humidity bin. The data acquisition module is composed of an infrared thermal imager array and a thermopile sensor group embedded into the surface of the dummy; the signal processing module is integrated with a multi-channel data synchronizer and an intelligent algorithm unit, the time synchronization precision of the multi-channel data synchronizer is smaller than or equal to 1ms, and the multi-channel data synchronizer is used for dynamically separating the radiation heat dissipation amount Qrad and the convection heat dissipation amount Qconv. According to the invention, multi-parameter synchronous measurement is adopted, information acquisition mechanisms such as infrared, thermopile and micro differential pressure sensors are integrated, and accurate separation of radiation and convection heat dissipation is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of thermal performance testing of clothing, and in particular to a comprehensive testing system and method for studying the radiation and convection heat dissipation mechanisms of clothing, which is suitable for evaluating the thermal comfort of clothing in extreme environments. Background Art

[0002] In the study of thermal comfort of clothing, the human body loses heat through three pathways: thermal radiation, thermal convection, and thermal conduction, of which radiation and convection are the main forms of heat dissipation. Traditional testing methods have the following shortcomings: (1) Single parameter test mode: Existing equipment (such as heated manikins) focuses on overall thermal resistance measurement, does not quantify the radiation / convection ratio, cannot separate radiation and convection heat dissipation, and is difficult to accurately analyze the heat dissipation mechanism; (2) Environmental simulation has limitations: The upper limit of the wind speed in traditional wind tunnels is 10m / s (see Journal of Textile Research, 2020, 41(5):1-7), which cannot simulate strong winds of 15m / s. In addition, the control accuracy of environmental variables such as wind speed, temperature and humidity is insufficient, and it is impossible to simulate actual wearing scenarios (such as strong winds and low temperatures); (3) Data integration capabilities are poor, data synchronization and systematization are insufficient, and the dynamic analysis of heat dissipation mechanisms under multi-parameter coupling has not been solved. Summary of the Invention

[0003] Technical problems solved: In response to the technical problems existing in the prior art, the present invention provides a comprehensive testing system and method for studying the radiation and convection heat dissipation mechanism of clothing. It adopts an environment-heat source-data ternary collaborative system, and the wind tunnel and the temperature and humidity chamber are linked to realize the simulation of the extreme environment of -50℃ / 15m / s strong wind; the local temperature difference of the partitioned thermal control unit is ≤0.5℃, which supports the heat dissipation analysis of key parts such as cuffs and collars; and the multi-source data fusion algorithm is adopted to improve the analysis capability of the test device.

[0004] Technical solution: The present invention provides a comprehensive testing system for studying the radiation and convection heat dissipation mechanism of clothing, comprising: A heated manikin model that simulates human physiological characteristics and adjusts its surface temperature based on demand, and includes zoned thermal control units for independent temperature control of the torso and limbs; An environmental control module, comprising a wind tunnel system and a temperature and humidity chamber; A data acquisition module, which is composed of an infrared thermal imager array and a thermopile sensor group embedded in the surface of the dummy; Signal processing module, the signal processing module integrates a multi-channel data synchronizer and an intelligent algorithm unit, the time synchronization accuracy of the multi-channel data synchronizer is ≤1ms, and is used to dynamically separate the radiated heat Q rad and convection heat dissipation Q conv .

[0005] Preferably, the intelligent algorithm unit is based on formula Q total =Q rad +Q conv , dynamically separates the radiation and convection heat dissipation and performs the following calculations: Radiative heat dissipation: Q rad =εσ(T 4 surface -T 4 ambient ); Initial convection heat dissipation: Q conv1 =h c •A•(T surface -T air ); Infrared verification of convection heat dissipation: Q conv2 =H / [A•(T surface -T air )]-Q rad ; Final convection heat dissipation: Q conv =(Q conv1 +Q conv2 ) / 2; In the above formula: ε is the clothing emissivity; σ is the Stefan Boltzmann constant, which is 5.67×10 -8 W / (m 2 •K 4 );h c =14.8v 0.69 , v is the wind speed; A is the clothing area factor; H is the average heat flux density.

[0006] Preferably, the wind tunnel system includes a guide plate, and the wind speed distribution uniformity error in the test area is ≤5%; the wind speed of the wind tunnel system adopts stepless speed regulation, and its wind speed adjustment range is 0.1-15m / s.

[0007] Preferably, the temperature adjustment range of the temperature and humidity chamber is -50-40°C, and the humidity adjustment range is 20-90%RH.

[0008] Preferably, the surface temperature of the warm-body manikin model has a control accuracy of ±0.2°C and an adjustment range of 33-37°C.

[0009] Preferably, the infrared thermal imager array has a wavelength of 7-14 μm and an accuracy of ±0.1°C.

[0010] Preferably, the data acquisition module supports extended access to a humidity response sensor.

[0011] The present invention also discloses a comprehensive testing method for studying the radiation and convection heat dissipation mechanism of clothing, which uses the above-mentioned comprehensive testing system and includes the following steps: Step 1: Set the surface temperature of the heated manikin model through the zoned thermal control unit; Step 2: Set the target environmental parameters in the temperature and humidity chamber, including temperature, humidity, and wind speed parameters; Step 3: Synchronously collect infrared thermal imager temperature distribution data and thermopile heat flux density data; Step 4: Dynamically separate radiation and convection heat dissipation through intelligent algorithms and verify the test results based on infrared data.

[0012] The present invention provides a comprehensive testing system and method for studying the radiation and convection heat dissipation mechanism of clothing, achieving the following technical effects: 1. The present invention adopts multi-parameter synchronous measurement and integrates information collection mechanisms such as infrared, thermopile, and micro-pressure differential sensors to achieve precise separation of radiation and convective heat dissipation (error <5%). The convective heat dissipation is corrected by thermal infrared equipment, and the analysis results are more accurate. 2. Using full-environment simulation, the wind speed adjustment range can reach 0.1-15m / s, the low temperature adjustment limit is -50℃, and it supports the combined test of -50℃ low temperature and 15m / s strong wind, which can cover extreme wearing scenarios; 3. Using high-precision dynamic analysis, data synchronization error ≤ 1ms, supporting the capture of transient heat dissipation processes (such as the impact of sudden changes in wind speed); 4. The zoned thermal control unit is used to ensure a local temperature difference of ≤0.5°C, supporting heat dissipation analysis of key areas such as cuffs and collars; 5. The modular structure allows for expansion and access to new sensors (such as humidity response units) as needed to adapt to future technological upgrades and modifications. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the framework structure of the comprehensive test system of the present invention; Figure 2 for Figure 1 Data synchronization flow chart of the integrated test system.

[0014] Figure numerals: 1. Warm manikin model; 2. Wind tunnel system; 3. Temperature and humidity chamber; 4. Infrared thermal imager array; 5. Thermopile sensor; 6. Signal processing module. DETAILED DESCRIPTION

[0015] To make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the following Figure 1-Figure 2 The technical solutions of the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present invention.

[0016] Example 1: Figure 1 As shown, the comprehensive testing system for studying the radiation and convection heat dissipation mechanisms of clothing, described in the present invention, includes a thermal manikin model 1, an environmental control module, a data acquisition module, and a signal processing module 6. The thermal manikin model 1 adjusts its surface temperature based on the needs of simulating human physiological characteristics. It includes zoned thermal control units for independent temperature control of the torso and limbs. The surface temperature of the thermal manikin model 1 is adjustable with an accuracy of ±0.2°C and an adjustment range of 33-37°C. It can use an industrial-grade PID controller such as the Yudian AI-516P, which supports 30-segment program control and multiple alarms, making it suitable for application scenarios such as biotechnology and heat treatment.

[0017] The environmental control module includes a wind tunnel system 2 and a temperature and humidity chamber 3. Wind tunnel system 2 features stepless speed regulation within a range of 0.1-15 m / s. It also includes deflectors and maintains a uniformity of wind speed within the test area of ​​≤5%. This wind tunnel system 2 provides wind power for the integrated test system to simulate diverse wind environments. The temperature and humidity chamber 3 has an adjustable range of -50-40°C and a humidity range of 20-90% RH, allowing for simulation of diverse temperature and humidity conditions.

[0018] The data acquisition module consists of an infrared thermal imager array 4 and five groups of thermopile sensors embedded on the surface of the dummy. The infrared thermal imager array 4 has a wavelength of 7-14μm and an accuracy of ±0.1°C. The infrared thermal imager array 4 can monitor the temperature change data of the warm-body dummy model 1 in real time. The data acquisition module reserves an RS485 / Ethernet interface and supports the addition of new sensors such as phase change material thermal response units and humidity response sensors.

[0019] Signal processing module 6 integrates a multi-channel data synchronizer and an intelligent algorithm unit. The time synchronization accuracy of the multi-channel data synchronizer is ≤1ms, which is used to dynamically separate the radiated heat Q rad and convection heat dissipation Q conv , infrared data, thermopile data, and environmental parameters are calculated synchronously through the FPGA chip. Among them, the intelligent algorithm unit is based on the formula Q total =Q rad +Q conv , dynamically separates the radiation and convection heat dissipation and performs the following calculations: Radiative heat dissipation: Q rad =εσ(T 4 surface -T 4 ambient ); Initial convection heat dissipation: Q conv1 =h c •A•(T surface -T air ); Infrared verification of convection heat dissipation: Q conv2 =H / [A•(T surface -T air )]-Q rad ; Final convection heat dissipation: Q conv =(Q conv1 +Q conv2 ) / 2; In the above formula: ε is the clothing emissivity; σ is the Stefan Boltzmann constant, which is 5.67×10 -8 W / (m 2 •K 4 );h c =14.8v 0.69 , v is wind speed, h c is the experimental fitting formula; A is the clothing area factor; H is the average heat flux density.

[0020] The present invention adopts multi-parameter synchronous measurement and integrates information collection mechanisms such as infrared, thermopiles, and micro-pressure differential sensors to achieve precise separation of radiation and convective heat dissipation (error <5%). The convective heat dissipation is corrected by thermal infrared equipment, and the analysis results are more accurate; full-environment simulation is adopted, the wind speed adjustment range can reach 0.1-15m / s, and the low temperature adjustment limit is -50℃. It supports the combination test of -50℃ low temperature and 15m / s strong wind, which can cover extreme wearing scenarios; high-precision dynamic analysis is adopted, and the data synchronization error is ≤1ms, which supports the capture of transient heat dissipation process (such as the impact of sudden changes in wind speed); the partitioned thermal control unit is adopted with a local temperature difference of ≤0.5℃, which supports heat dissipation analysis of key parts such as cuffs and collars; a modular structure is adopted, and new sensors (such as humidity response units) can be expanded and connected according to needs to adapt to future technology upgrades and modifications.

[0021] Example 2: Figure 2 As shown, the present invention also discloses a comprehensive testing method for studying the radiation and convection heat dissipation mechanism of clothing, which adopts the above-mentioned comprehensive testing system and includes the following steps: Step 1: Setting the surface temperature of the warm manikin model 1 through the zoned thermal control unit; Step 2: Set target environmental parameters in the temperature and humidity chamber 3, including temperature, humidity, and wind speed parameters; Step 3: Synchronously collect infrared thermal imager temperature distribution data and thermopile heat flux density data; Step 4: Dynamically separate radiation and convection heat dissipation through intelligent algorithms and verify the test results based on infrared data.

[0022] Based on the above embodiment, taking the extreme environment test of down jackets as an example, first, the surface temperature of the thermal manikin model 1 was set to 35°C, and the temperature and humidity chamber 3 was set to -20°C and 30% RH. Then, the wind tunnel system 2 was started and the speed was adjusted stepwise from 0.5 to 10 to 15 m / s. Finally, data was collected and the intelligent algorithm was run simultaneously. The core code of the algorithm is as follows: Q rad =εσ(T 4 surface −T 4 ambient ); h c =14.8v 0.69 ; Q conv1 =h c •A•(T surface -T air ); Q conv2 =H / [A•(T surface -T air )]-Q rad ; Q conv =(Q conv1 +Q conv2 ) / 2.

[0023] Calculations show that when the wind speed is 10m / s, the convective heat dissipation accounts for 96.5%, and the radiant heat dissipation drops to 3.5%.

[0024] In another specific embodiment, heat dissipation analysis is performed on a localized part of the human body, for example, the cuff of the right arm of a thermal manikin 1 is used as an example: the infrared thermal imager detects a temperature difference of ΔT = 3.2°C in this area (0.8°C higher than the torso); the intelligent algorithm identifies a peak convective heat flux density of 152W / m², indicating that this is a weak heat dissipation area.

[0025] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A comprehensive testing system for studying the radiation and convection heat dissipation mechanism of clothing, characterized by: include: A warm-body manikin model (1), wherein the warm-body manikin model (1) adjusts the body surface temperature according to the needs of simulating the physiological characteristics of the human body, and comprises a zoned thermal control unit for independently controlling the temperature of the trunk and limbs; An environmental control module, the environmental control module comprising a wind tunnel system (2) and a temperature and humidity chamber (3); A data acquisition module, the data acquisition module being composed of an infrared thermal imager array (4) and a thermopile sensor (5) group embedded in the surface of the dummy; Signal processing module (6), the signal processing module (6) integrates a multi-channel data synchronizer and an intelligent algorithm unit, the time synchronization accuracy of the multi-channel data synchronizer is ≤1ms, and is used to dynamically separate the radiation heat dissipation Q rad and convection heat dissipation Q conv .

2. The comprehensive testing system for studying clothing radiation and convection heat dissipation mechanism according to claim 1 is characterized in that: The intelligent algorithm unit is based on the formula Q total =Q rad +Q conv , dynamically separates the radiation and convection heat dissipation and performs the following calculations: Radiative heat dissipation: Q rad =εσ(T 4 surface -T 4 ambient ); Initial convection heat dissipation: Q conv1 =h c •A•(T surface -T air ); Infrared verification of convection heat dissipation: Q conv2 =H / [A•(T surface -T air )]-Q rad ; Final convection heat dissipation: Q conv =(Q conv1 +Q conv2 ) / 2; In the above formula: ε is the clothing emissivity; σ is the Stefan Boltzmann constant, which is 5.67×10 -8 W / (m 2 •K 4 );h c =14.8v 0.69 , v is the wind speed; A is the clothing area factor; H is the average heat flux density.

3. The comprehensive testing system for studying clothing radiation and convection heat dissipation mechanism according to claim 1 is characterized in that: The wind tunnel system (2) includes a guide plate, and the wind speed distribution uniformity error in the test area is ≤5%; the wind speed of the wind tunnel system (2) adopts stepless speed regulation, and the wind speed adjustment range is 0.1-15m / s.

4. The comprehensive testing system for studying clothing radiation and convection heat dissipation mechanism according to claim 1 is characterized in that: The temperature and humidity chamber (3) has a temperature adjustment range of -50-40°C and a humidity adjustment range of 20-90%RH.

5. The comprehensive testing system for studying clothing radiation and convection heat dissipation mechanism according to claim 1 is characterized in that: The surface temperature of the warm-body manikin model (1) has a control accuracy of ±0.2°C and an adjustment range of 33-37°C.

6. The comprehensive testing system for studying clothing radiation and convection heat dissipation mechanism according to claim 1 is characterized in that: The infrared thermal imager array (4) has a wavelength of 7-14 μm and an accuracy of ±0.1°C.

7. The comprehensive testing system for studying clothing radiation and convection heat dissipation mechanism according to claim 1 is characterized in that: The data acquisition module supports extended access to humidity response sensors.

8. A comprehensive testing method for studying the radiation and convection heat dissipation mechanism of clothing, characterized in that: The integrated test system according to any one of claims 1 to 6 comprises the following steps: Step 1: Setting the surface temperature of the warm-body manikin model (1) through the zoned thermal control unit; Step 2: Set the target environmental parameters in the temperature and humidity chamber (3), including temperature, humidity, and wind speed parameters; Step 3: Synchronously collect infrared thermal imager temperature distribution data and thermopile heat flux density data; Step 4: Dynamically separate radiation and convection heat dissipation through intelligent algorithms and verify the test results based on infrared data.

Images