【作者】 张文灿；

【导师】 陈吉清；

【作者基本信息】 华南理工大学 ， 车辆工程， 2013， 博士

【摘要】 随着城市发展和生活方式的改变，汽车已经从过往的奢侈品逐步过渡为大众消费品，成为城市生活不可缺少的一部分，人们在汽车上度过的时间日益增加，汽车乘坐空间热环境开始成为广大消费者、研究人员和汽车厂商的关注一个热点和焦点问题。一方面车内热环境和乘员热舒适性密切相关，车内的空气温度、相对湿度、气流速度和平均辐射温度等环境因素都直接影响着乘员的乘坐舒适性；另一方面汽车乘坐空间热环境和乘员热舒适性又严重影响着汽车的燃油经济性，尤其是动力系统由内燃机转变为电池系统的新兴电动汽车，电动汽车空调所消耗的能量都来源于动力电池，车内热环境控制已经成为电动汽车研究人员面临的一个全新挑战。在此背景下，汽车乘坐空间热环境热与乘员热舒适性的研究，不仅是提高整车的能源利用率、降低外部环境对车内热环境的影响，实现对车内热环境进行科学高效热管理的迫切需要；同时也为制定舒适、节能的车内热环境标准提供科学依据和理论指导，对构建节能、舒适、安全的汽车乘坐环境具有深远意义。在综述国内外关于汽车乘坐空间热环境与乘员热舒适性相关研究文献的基础上，总结分析国内外的研究现状和不足，由此以建立完整的汽车乘坐空间热环境与乘员热舒适分析体系为主线，提出本文的研究内容。首先通过试验研究方法对我国南方气候环境下某中级车车内热环境参数进行试验测试，对不同的气候下车内外太阳辐射、温度及湿度等环境变量的分布情况进行分析说明，系统了解汽车乘坐空间热环境的基本情况，为后续车内热环境数值分析提供依据和验证数据。针对目前已有人体热舒适评价方法在汽车乘坐空间热环境下应用的不足，通过试验方法对车内瞬态非均匀热环境下乘员头部、胸部、腹部、背部、上臂、下臂、手、大腿、小腿和脚这10个部位进行皮肤温度测试，同时采用ASHRAE7点标尺对乘员局部热感觉进行相应的主观评价，应用数理统计分析方法拟合皮肤表面温度与乘员局部热感觉之间的关系，建立基于乘员皮肤表面温度的乘员热感觉及热舒适性客观评价方法，弥补国内关于乘员热舒适评价方法研究的空白，为本文后续研究提供科学可行的评价方法。在试验研究结论的基础上，根据汽车车身壁面传热数学模型建立其传热数值计算模型，并通过试验测试数据验证了数值模型的有效性，对车身壁面与外部太阳辐射、车内表面发射辐射、内外表面传导等传热过程进行仿真分析，计算壁面温度及不同形式传热热流量的动态变化过程，分析壁面热环境的主要影响因素。在基准模型的基础上，探索通过改变汽车车身特性来达到降低太阳辐射对车内热环境影响的方法及效果，分析结果表明改变车窗玻璃光学特性及车身外表面特性都可以有效降低外部环境因素对车内热环境的影响作用，为汽车设计以及乘员热舒适性研究提供参考。在汽车乘坐空间“热-流”场分布特性研究方面，首先从理论上分析流体力学计算模型及边界层的处理方法，讨论自然对流传热在车内的权重和影响作用，为车内自然对流计算和简化提供科学依据。随后采用固体壁面传热和车内流体流动与传热耦合仿真模型，建立可以考虑外部环境动态影响的完整的车内“热-流”场数值分析模型，并在我国南方夏季气候环境下对空调制冷过程中车内“热-流”场动态特性进行耦合数值仿真，重点讨论分析车内流体流动和温度动态分布规律和一般设计准则。最后根据人体热调节理论基础及数学模型，建立基于人体实际形状几何模型的乘员热调节数值模型，该模型共将乘员划分为14个不同的组成部分，每个部分又细分为4个层次。然后将人体热调节模型与所建立的车内热环境数值计算模型组成耦合仿真模型，建立完整的车内乘员热舒适性数值分析模型，计算在车内瞬态非均匀热环境下人体皮肤表面温度动态变化过程，并利用所建立的乘员热舒适性评价方法对乘员在空调制冷过程中的热舒适性动态变化过程进行详细分析，讨论乘员热感觉及热舒适变化的一般规律。本文对汽车乘坐空间热环境，乘员热舒适性评价方法，以及相关数值仿真方法关键技术所研究得到的成果，解决了汽车乘坐空间热环境和乘员热舒适分析中一些关键共性技术、共性规律和设计原则，丰富和完善了现有的研究体系，具有良好的理论和工程应用价值。更多还原

【Abstract】 With the development of city and the change of citizens’ lifestyle, vehicles havegradually changed to mass consumer goods from luxury in the past, and become anindispensable part of urban life. People spend more and more time in the vehicle cabins, thenthe thermal environment in vehicle cabins has aroused wide attention from consumers,researchers and car manufacturers. The thermal environment in vehicle cabins is closelyrelated to occupants’ thermal comfort, the air temperature, relative humidity, flow velocity,mean radiant temperature and other environmental factors are known to afect the ridingcomfort of occupants. On the other hand, the thermal environment in vehicle cabins and theoccupants’ thermal comfort are seriously affecting the fuel economy of the vehicle, especiallyfor the electric vehicles. All the energy used for the cabins heating or cooling in electricvehicles is supplied by the main battery which is expected to be used to drive. Operation ofthe air-conditioning system thus has a major influence on battery’s cruising range, which isone of the bottlenecks to restrict electric vehicle’s development. Under this background,thermal environment and occupant’s thermal comfort in vehicle cabins research is not onlythe urgent need to improve the energy efficiency of the vehicle, reduce the impact of theexternal environment on the interior thermal environment, then to achieve scientific andefficient thermal environment thermal management in vehicles cabins; but also fordevelopment of comfortable, energy-efficient thermal environment standards in vehiclescabins providing a scientific basis and theoretical guidance, it has far-reaching significancefor constructing energy-efficient, comfortable and safe vehicles cabins environment.With comprehensive reviewing of the thermal environment and occupant’s thermalcomfort in vehicle cabins research in open literature, this paper analyzed and summarizedtheir advantages and limitations, thus proposed to build a complete transient thermalenvironment and occupant’s thermal comfort analysis system as the main line, put forward theresearch contents in this paper. Firstly, with the purposes of understanding the basic thermalconditions in the cabin of a typical Mittelklasse, the solar radiation inside and outside thecabin, the distribution of temperature and humidity and other environmental variables underdifferent climate in south China were experimental measured and analyzed. Furthermore, themeasurement data would provide the analysis basis and validation data for the subsequentthermal environment numerical study.According to the deficiencies of current occupant’s thermal comfort evaluation methodsin the vehicle cabins thermal environment, this paper tested the skin temperature of occupant’s head, chest, abdomen, back, upper arms, lower arms, hands, thighs, legs and feet under thetransient and non-uniform thermal environment in the cabin, while using the ASHRAE7-points scale to evaluate the local thermal sensation of corresponding body parts, then usingthe mathematical statistical analysis method to investigate the relationship between the skintemperature and the local thermal sensation of corresponding body part. Finally, establishing anew objective occupant’s thermal comfort evaluation methods based on the occupant’s skintemperature, providing scientific and feasible evaluation method for the follow-up study inthis paper and making up the blank of domestic occupant’s thermal comfort evaluationmethod.Based on the conclusions of experimental study and according to the heat transfermathematical model of car body, the numerical calculation model was established andvalidated in this paper. Then, the solar radiation, the wall emitting radiation and theconduction heat transfer process, etc. on the interior wall were simulated; the wall temperaturedistribution and the heat flow flux of different heat transfer process were calculated throughthe established numerical model. Based on the numerical results, this paper, furthermore,analyzed the main influencing factors of surface thermal environment in vehicle cabins. Onthe basis of the benchmark model, this paper investigated means to reduce the influence ofsolar radiation on the thermal environment in vehicle cabins by changing car body features.The resulted showed that it can effectively reduce the impact of the external environmentalconditions on the vehicle cabins by changing the window glass optical properties as well asthe surface characteristics of the car body. These conclusions would provide valuablereferences for the vehicle design and the occupant’s thermal comfort study.In the aspect of “temperature-flow” distribution characteristics investigation in vehiclecabins, this paper firstly theoretically analyzed the computational fluid dynamics model andthe boundary layer treatment approach, discussed the influence of natural heat transfer andobtained the simplification basis of the numerical approach of vehicle cabins. Then couplingthe solid wall heat transfer and the fluid flow and heat transfer model, this paper established acompleted coupled numerical model of thermal environment in vehicle cabins, which canconsider the influences of external environment conditions. With the coupled numericalmodel, this paper simulated the “temperature-flow” dynamic characteristics in vehicle cabinsin the process of air-conditioning refrigeration under south China climate and analyzed thefluid flow and temperature dynamic distribution inside the cabin as well as the generalguidelines of the cabin’s thermal management design.Finally, according to the human thermal regulation theory and mathematical model, based on the occupant geometric model this paper established an occupant thermal regulationnumerical model, this model divided the body of occupant into14different components, andeach component was subdivided into four levels. Then coupling the occupant thermalregulation and the thermal environment numerical model, this paper established a completedcoupled numerical model of occupant’s thermal comfort analysis. With the coupled thermalcomfort analysis model, this paper calculated the occupant’s skin temperature under thetransient and non-uniform thermal environment in vehicle cabin, and used the establishedoccupant’s thermal comfort evaluation method to detailed analyzed occupant’s thermalcomfort in the process of air-conditioning refrigeration, and discussed the general law of theoccupant’s thermal sensation then the thermal comfort in vehicle cabins.The thermal environment coupled simulation methods, the occupant’s thermal comfortevaluation method, as well as the main conclusions obtained in this paper, solved some keycommon technologies, rules and design principles during the thermal environment andoccupant’s thermal comfort analysis in vehicle cabins, enriched and improved the existingresearch system, had a good theory and engineering application value in vehicle design.更多还原