Abstract

The European transportation sector employs 10 million people and accounts for 4.6% of the European Union GDP. Due to climate change, this workforce is increasingly affected by high temperatures and radiant loads, particularly during summer. They rely on air conditioning (AC) to minimize heat inside the truck cabins, increasing fuel consumption and tailpipe emissions. Because sustainable transportation is crucial for climate change mitigation, we developed a numerical investigation on the dynamic thermal exchanges of cabins of heavy-duty trucks in realistic conditions of a summer workday, to quantify the potential impact of interventions in the glazing and paint optical properties, over the truck AC loads. We observed that the changes in air temperature and solar irradiation throughout the workday imply substantial variations in the truck’s AC loads and, consequently, in its fuel consumption and tailpipe emissions. Furthermore, windshields and side windows with transmissivity of 0.33 instead of typical 0.79 and 0.84, respectively, can reduce AC loads by up to 16%. External paints with reflectivity of 0.70 instead of 0.04 can reduce the AC loads by up to 30%, whereas cumulative changes to glazing and paint can reduce the AC load by up to 40%. These interventions can lower fuel consumption and emissions by up to 0.4%. These results show that important improvements in fuel efficiency and tailpipe emissions are possible, if the research community, policy makers and industry stakeholders successfully promote the adaptation of the European transportation fleet.

摘要

欧洲交通部门雇佣了 1000 万人，占欧盟 GDP 的 4.6%。由于气候变化，这些劳动力越来越受到高温和辐射负荷的影响，尤其是在夏季。他们依靠空调 (AC) 来最大限度地减少卡车车厢内的热量，从而增加燃料消耗和尾气排放。由于可持续交通对于减缓气候变化至关重要，我们对夏季工作日现实条件下重型卡车车厢的动态热交换进行了数值研究，以量化干预对玻璃和油漆光学特性的潜在影响，超过卡车交流负载。我们观察到，工作日期间气温和太阳辐射的变化意味着卡车的交流负载发生了显着变化，因此，其燃料消耗和尾气排放也发生了显着变化。此外，透射率分别为 0.33 而非典型的 0.79 和 0.84 的挡风玻璃和侧窗可将交流负载降低多达 16%。反射率为 0.70 而不是 0.04 的外部涂料可以将交流负载降低多达 30%，而对玻璃和油漆的累积变化可以将交流负载降低多达 40%。这些干预措施可以将燃料消耗和排放降低多达 0.4%。这些结果表明，如果研究界，