Suchergebnisse

Infrared-reflective (IRR) treatment of automotive glass has been shown to reduce air temperature in vehicle cabins, thereby increasing fuel economy and occupant comfort. Its effect on radiant heat, however, may augment these benefits. In this study, the hypothesis that radiant heat affects subjective comfort ratings in a vehicle was tested. IRR films were systematically applied to the driver-side window of an outdoor stationary vehicle. In Phase 1, cabin air temperature was controlled while participants rated their thermal comfort. In Phase 2, air temperature was adjusted according to participants' responses. Results in Phase 1 showed that the IRR treatment improved thermal comfort on the left forearm, which was exposed to direct solar irradiance, but not whole-body thermal comfort. In Phase 2, participants indicated that they were comfortable at a higher air temperature (mean of 2.5°F [1.4°C]) with the IRR treatment than in the untreated condition. The results indicate that reducing radiant heat via IRR treatment affects subjective assessments of thermal comfort and allows occupants to maintain the same level of comfort in a warmer vehicle cabin. Applications of this research include future implementations of IRR treatment on automotive glass that may lead to greater fuel economy savings and occupant comfort than have previously been estimated.

Energy-poor households in Africa's burgeoning urban informal settlements are especially likely to suffer from heatwaves because of thermally inefficient dwellings and lack of affordable cooling options. This study utilised a controlled experiment to assess the effectiveness of passive cooling through specially formulated paints (cool coatings) in standard informal structures. The test structures were built to simulate typical shack dwellings in South Africa's urban informal settlements. Results showed that the mean daily maximum temperatures of the coated structure were up to 4.3 °C lower than those in the uncoated structure. The same cooling trend was observed for the minimum daily temperatures, which were lower by an average of 2.2 °C. Besides, the annual frequency of maximum temperature exceedances beyond the critical heat stroke value of 40 °C dropped from 19% for the uncoated structure to 1% for the coated structure. These temperature differences were found to be statistically and subjectively significant, implying that cool coatings may be effective in promoting thermal comfort and climate resilience in poor urban communities. It is recommended that governmental authorities and relevant role players invest in the production and assisted application of cool coatings in urban informal settlements. The interventions promise hope of reduced energy burden on poor households and could be implemented in parallel with ongoing efforts focused on the design and implementation of low-cost, durable and thermally comfortable houses for indigent communities. Ultimately, the endeavours could be a potential policy change to assist in expanding poor households' access to alternative and green energy resources.

Energy-poor households in Africa's burgeoning urban informal settlements are especially likely to suffer from heatwaves because of thermally inefficient dwellings and lack of affordable cooling options. This study utilised a controlled experiment to assess the effectiveness of passive cooling through specially formulated paints (cool coatings) in standard informal structures. The test structures were built to simulate typical shack dwellings in South Africa's urban informal settlements. Results showed that the mean daily maximum temperatures of the coated structure were up to 4.3 °C lower than those in the uncoated structure. The same cooling trend was observed for the minimum daily temperatures, which were lower by an average of 2.2 °C. Besides, the annual frequency of maximum temperature exceedances beyond the critical heat stroke value of 40 °C dropped from 19% for the uncoated structure to 1% for the coated structure. These temperature differences were found to be statistically and subjectively significant, implying that cool coatings may be effective in promoting thermal comfort and climate resilience in poor urban communities. It is recommended that governmental authorities and relevant role players invest in the production and assisted application of cool coatings in urban informal settlements. The interventions promise hope of reduced energy burden on poor households and could be implemented in parallel with ongoing efforts focused on the design and implementation of low-cost, durable and thermally comfortable houses for indigent communities. Ultimately, the endeavours could be a potential policy change to assist in expanding poor households' access to alternative and green energy resources

International negotiations on the reduction of greenhouse gas emissions turn out to be ineffective more and more, which means that global warming is not very likely to be stopped in a manageable period of time. Therefore adaptation to climate change increasingly becomes an important topic in planning and decision-making. While the reduction of greenhouse gas emissions is a global topic, adaptation to climate change is an issue that necessarily needs consideration of local peculiarities. This research contributes to an understanding of thermal comfort, which is characterized by a strong spatial variation on a local level and therefore deserves an in-depth analysis within a framework of case studies. In general, this study seeks to create a repository of adaptation and mitigation strategies, out of Iranian traditional urbanism and adaptation activities performed in the Ruhr area. Since these strategies were mostly too broad to be covered in a single research, much delimitation had to be performed. Eventually two main groups of strategies emerged: One that focused on the thermal comfort situation of pedestrians and the second group that was dedicated to energy. Naturally, these two groups constitute the pillars of this research. This study, also seeks to explore the applicability of such strategies to the Iranian contemporary cities, particularly those with hot and dry climate around the central Iranian desert. To investigate the effects of the alterations in the urban fabric on the pedestrian thermal comfort, microclimate simulations are performed. Several factors of the built environment, such as the existence of balconies and urban vegetation, are introduced and their impact on the local microclimate is examined. Eventually, out of many possible scenarios performed, an optimized setting is extracted and studied for verification. Concerning the energy section, a cost-benefit analysis is performed to investigate the financial feasibility of the adoption of renewable energies in the current context of Iran. The results reveal that unless there is a massive change in the structure of governmental funding and investments in the renewable energy sector, it will not be affordable to the general public. The outcome of this research is a set of suggestions to be incorporated into the Iranian urban design codes, both on local and regional scales that will facilitate a climate conscious urban development based on scientific facts and evidences.

The microclimate is a particularly important environmental aspect in operating rooms (ORs), where more than in other hospital environments, it is extremely important, and at the same time extremely difficult, to reconcile the needs of different types of occupants (patients and operators). Moreover, unsuitable microclimatic conditions may affect the onset of infection. The present study aimed to analyze the periodic monitoring of the microclimatic conditions carried out in ORs over 10 years, to verify the adequacy of the thermal comfort conditions for all occupants. The evaluation of thermal comfort was carried out using the Fanger indices and the standards required by current legislation and specific guidelines. Non-compliant values for at least one parameter were found in 98.8% of the examinations performed in the ORs. A condition of thermal discomfort was calculated for 3.6% of healthcare professionals and 98.3% of patients. The monitoring of microclimatic conditions is particularly important in the OR as an indicator of inadequate functioning of the air conditioning system, which might affect the thermal comfort of all occupants and lead to microbial contamination of the room.

The hydrothermal microclimate is the main component in indoor comfort. The optimum hydrothermal level can be ensured by suitable changes in the sources of heat and water vapor within the building, changes in the environment (the interior of the building) and in the people exposed to the conditions inside the building. A change in the heat source and the source of water vapor involves improving the heat - insulating properties and the air permeability of the peripheral walls and especially of the windows. The change in the environment will bring human bodies into balance with the environment. This can be expressed in terms of an optimum or at least an acceptable globe temperature, an adequate proportion of radiant heat within the total amount of heat from the environment (defined by the difference between air and wall temperature), uniform cooling of the human body by the environment, defined a) by the acceptable temperature difference between head and ankles, b) by acceptable temperature variations during a shift (location unchanged), or during movement from one location to another without a change of clothing. Finally, a moisture balance between man and the environment is necessary (defined by acceptable relative air humidity). A change for human beings means a change of clothes which, of course, is limited by social acceptance in summer and by inconvenient heaviness in winter. The principles of optimum heating and cooling, humidification and dehumidification are presented in this paper.Hydrothermal comfort in an environment depends on heat and humidity flows (heat and water vapors), occurring in a given space in a building interior and affecting the total state of the human organism.