Daylight and Thermal Comfort Study

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Thermal comfort study on terraced house overseeing the effect on rainwater harvesting system

Thermal comfort study on terraced house overseeing the effect on rainwater harvesting system

Effective shading can be provided by various means, including dedicated shading devices, nearby structures, vegetation and special glasses. Generally, external shading devices are considered the most effective, since they intercept solar radiation before it passes through the building envelope into the interior space. An appropriately orientated high-pitched roof which affords self-shading and allows only one side of itself to received direct solar radiation at a time is another possible shading technique [46] . A key issue which should be considered in shading design is its tendency to conflict with day lighting. Reduced daylight penetration due to inappropriate shading design can increase the demand for artificial lighting, which then offsets the energy savings from reduced heat gains [47] . Such a conflict can be lessened, for example, by using interior surfaces of high reflectance values, such as those in light colors, or using light shelves to reflect daylight into the deeper part of the interior [47] . Movable shading devices, such as louvers, which allow the occupants to adjust their local lighting and thermal environment, are another solution. When shading is provided by a special glass, the choice of glass is essential for balancing the benefit of heat gain reductionwith that of day lighting. Work is still required to identify the appropriate types of glass for free running buildings in hot humid climates, although some suggestions have been made with regard to their air- conditioned counterparts. Overall, research opportunity is still open for developing quantitative principles of shading that will balance thermal and energy benefits with day lighting quality. Shading as provided by vegetation is discussed in Section 3.4.
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Daylight Performance of a Translucent Textile Membrane Roof with Thermal Insulation

Daylight Performance of a Translucent Textile Membrane Roof with Thermal Insulation

Abstract: Daylight usage in buildings improves visual comfort and lowers the final energy demand for artificial lighting. The question that always occurs is how much conservation can be achieved? New or rare materials and constructions have a lack of information about their application. Therefore, the current investigation quantifies the daylight and energy performance of a rare multi- layer textile membrane roof. A translucent, thermal insulation with a glass fibre fleece between the two roof membranes combines daylight usage and heating demand reduction. A sports hall built in 2017 is used as a case study building with 2300 m 2 membrane roof surface. The optical properties of
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Green Areas and Microscale Thermal Comfort in Arid Environments: A Case Study in Mendoza, Argentina

Green Areas and Microscale Thermal Comfort in Arid Environments: A Case Study in Mendoza, Argentina

A series of mobile and stationary meteorological measurements were performed in the city of Mendoza, Argentina to study the local influence of green areas on the urban canopy layer heat island effect at the micro scale, during the Aus- tral summer of 2003-2005. These results were associated in representative local climate zones (LCZ), which helped to identify different thermal conditions within the city. The physiologically equivalent temperature index was used to de- termine the thermal comfort in each LCZ, showing that during daylight, trees and parks improve thermal comfort through shading and evapotranspiration; but at the same time, urban tree corridors delay night cooling by retaining warm air beneath their canopies. Also irrigation showed to positively influence on the extension and intensity of the cooling effect of rural areas and parks. The cooling influence of an urban park spreads out through the neighborhoods for 800 - 1000 m, with an average temperature decrease of 1.3˚C during daytime and >4.0˚C at nighttime.
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Thermal comfort study for student laboratory

Thermal comfort study for student laboratory

From the related sources, some of the problem statements had found which relevant to the effects of the thermal comfort or discomfort in the environment of classrooms. People working in uncomfortably hot and cold environments are more likely to behave unsafely. This is because their ability to make decisions or perform manual tasks deteriorates as mentioned in previous research by Paulo (2004). A long side these Budaiwi (2007) state that undesirable thermal conditions can lead to occupant dissatisfaction, which in turn has an adverse effect on their health, productivity, and performance By implementing this case study in UTeM‘s laboratories, thermal discomfort can be prevent therefore students can performed at their best level. Orosa (2010) found that, in order to conduct a research in the field of thermal comfort, there are six most important thermal variables such as the human activity level, clothing insulation, mean radiant temperature, humidity, temperature and velocity of the indoor air. Those thermal variables will be the main parameters to assess the thermal comfort level in student laboratories for this project.
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Neutral thermal sensation or dynamic thermal comfort? Numerical and field test analysis of a thermal chair

Neutral thermal sensation or dynamic thermal comfort? Numerical and field test analysis of a thermal chair

temperature (thermal preference). When they were offered with a thermal chair, 13 of them (87%) used the heating on the back and 14 of them (93%) used the temperature settings of the seat. Also, after using the thermal chair 13 of them (87%) ended up with a thermal sensation warmer than neutral and 11 of them (73%) did not want to feel neutral (thermal decision) after using the chair. 12 of them (80%) felt comfortable and 11 of them (73%) were satisfied with the overall thermal environment. In case the neutral thermal sensation would be the ideal feeling, it would be expected that either they don’t use the thermal chair and leave the temperature control off, and in case they applied temperature control, their comfort and satisfaction levels to drop. However, they reported 20% higher comfort and 33% higher satisfaction levels. Overall, 42% of the respondents, who felt neutral (thermal sensation) before or after using the thermal chair reported to feel between uncomfortable to slightly comfortable and 47% of them reported to feel dissatisfied to slightly satisfied with the overall thermal condition. In addition, 72% of the respondents, who did not feel neutral (thermal sensation) before or after using the thermal chair reported to feel comfortable and 65% reported to be satisfied with the overall thermal condition. The results indicated that a neutral thermal sensation does not guarantee thermal comfort. This finding is in agreement with the findings of Shahzad [8] and Humphreys and Hancock [9]. This study suggests that thermal comfort is dynamic and other thermal sensations than neutral need to be considered as the state of thermal comfort. The use of multi methods to assess thermal comfort is recommended. For instance, the use of thermal preference, thermal decision, comfort and satisfaction of the thermal environment is a more accurate approach to assess thermal comfort. This study questions the findings of any research that solely relies on thermal sensation and particularly on the neutral thermal sensation to assess thermal comfort of the occupants. Finally, the results emphasised the importance of the application of numerical modelling in evaluating the thermal performance of the chair.
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Desiccant Cooling System for Thermal Comfort: A Review

Desiccant Cooling System for Thermal Comfort: A Review

Khalid and Nabeel [43] (2001) evaluated the performance of solar assisted heat and desiccant cooling system for a domestic two storey residence located in Baghdad. A computer simulation was developed to assess the effects of various designs and operating conditions on the performance of the system and its components. The variable base degree -day method was employed in order to incorporate the hourly variations of solar heat gain and internal heat gains of the apace in the estimation of the heating load. The transfer function method was used to evaluate the hourly variations of cooling load. Only two collectors in series are applied to get the regeneration temperature i.e. 62 C at an air mass flux of 0.06 kg/s.m2 at mid day in July while a 36 C outlet temperature was achieved foe the same array and mass flux in Jan. The result of simulation of the solar air heating system indicated that the major design parameter is the collector area. The effect of air mass flux through the collector was not significant. Simulation study showed that the ambient temperature, regeneration temperature, heat exchanger effectiveness and evaporative cooler effectiveness have major influence on the system performance, whereas the dehumidifier has a minor effect.
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A Modified Approach to Analyze Thermal Comfort  Classification

A Modified Approach to Analyze Thermal Comfort Classification

India is a large country with varying geographical and climatic features. There are wide varieties of terrains like mountains (the Himalayas) in the north, delta region (the Ganges delta), desert (the Thar Desert) in the west, pla- teau (the Deccan plateau) in central India, coastal line (Eastern and Western) in the southern part of the country, and islands located off the mainland India (Lakshadweep and Andaman and Nicobar Islands) etc. Indian climate and size can be equivalent to what would be when vari- ous European countries put together would form. India is also varying in its culture and has always been successful in attracting a large number of tourists. Tourist comes here throughout the year and from various parts of the world. Tourist activities are sensitive to weather informa- tion which is expected to influence tourist destination selection, tourism activity participation, tourism demand, and tourism seasonality [19]. Comfort indices could broadly help in estimation of cooling energy requirements of the mega-cities of India and also assist in knowing the best periods of the year from a tourism point of view. The ever increasing urbanization in megacities of India like Delhi has led to increase in ambient temperatures over past few decades [20]. In such scenarios, comfort indices are an important tool to analyse impact of changing cli- mate on human population.
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Outdoor Microclimate Observation for Thermal Comfort in Harsh Desert Condition: A Study in Kashan Iran

Outdoor Microclimate Observation for Thermal Comfort in Harsh Desert Condition: A Study in Kashan Iran

Abstract Traditional architecture of the historical cities of Iran contains valuable lessons related to architecture and urban design. A group of these strategies are those used in outdoor urban spaces in desert cities providing a safe and sustainable microclimate for pedestrian. This research paper will highlight some of these strategies by doing a field study research in hot summer and cold winter in Kashan, a historical city of Esfahan Province. The weather data are collected in 11-12 July 2011 and 11-12 Jan 2012 by a mobile Kestrel Personal Weather station in the traditional part of the city. The collected data are analyzed for human thermal condition by UTCI (Universal Thermal Climate Index) on the psychrometric chart. The different thermal zones on this chart are compared with people’s behaviour according to their exposure time, clothing and activity. The collected weather data of observation days are compared in four levels of long-term meso climate, short-term meso climate, local climate and microclimate. To speed up the analyzing process a new software is designed called SIKRON. The result of this research has shown the effect of architectural strategies on modifying the microclimate condition in hot summer and cold winter for outdoor living in hot-arid climate.
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Dominant causes of cooling in automobile vehicles for thermal comfort

Dominant causes of cooling in automobile vehicles for thermal comfort

The PMV index provides a score that corresponds to the ASHRAE thermal sensation scale and represents the average thermal sensation felt by a large group of people. The PMV establishes thermal strain based on a steady state heat transfer between the human body and thermal comfort ratings from panel subject. The PMV has been proposed and established for homogenous conditions only and when applied in non-homogenous conditions as the case in vehicular cabins, it did not provide accurate prediction. In PMV index measurable parameters were taking into consideration, such as a band of interior temperature and humidity range that is prescribed to satisfy at least 80% of the vehicle occupants. PMV index can be determined when the personal factors (human activity level and clothing insulation) are estimated and the environmental factors (air temperature, air velocity, radiant temperature and relative humidity) are measured. Fanger also noted that the values of PMV are not sufficient to define the feeling of discomfort, as slightly warm or too cold, don‟t express how dissatisfied people are. Therefore, the idea of Predicted Percentage of Dissatisfied (PPD) was associated to the PMV calculation. The PPD calculates a prediction of the number of thermally dissatisfied people.
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An analysis of thermal comfort in primary schools in Vietnam

An analysis of thermal comfort in primary schools in Vietnam

All thermal comfort environments were measured in the early morning in both seasons. During the school time, the indoor temperature increased and reached the peak at 2:00 p.m. – 3:00 p.m., then began to cool down. Even so, there were no measured condition in comfort zone in the late afternoon. It is possible that the overheating problem may occur during school time, especially in the afternoon, even in the coldest season. Although more naturally ventilated classrooms in the coldest season were in comfortable and acceptable conditions, the primary schools generally in both seasons did not achieve thermal comfort based on the Vietnamese Building Standard. During the investigation periods, all of classrooms in which the measured temperatures were over 27 o C could be
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Thermal Comfort in a Naturally-Ventilated Educational Building

Thermal Comfort in a Naturally-Ventilated Educational Building

Climate-chamber studies done in the 1970’s at the Institute for Environmental Research at Kansas State University by Rohles and Nevins (1971) and Rohles (1973) showed that there are correlations between comfort level, temperature, humidity, sex, and length of exposure. Rohles (1980) concluded: “To deny or ignore the psychology involved in comfort measurement is not only shortsighted, but treats the human subject as a machine, which it is not”. Rohles (1981) also indicated that alongside control of physical variables, adjustments in the amount of furnishing in a space and lighting levels could probably provide a solution to improving thermal comfort. Their results, with various equations for predicting thermal sensation, have been published in ASHRAE Handbook of Fundamentals (2005:8.12).
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A Perspective of the Diurnal Aspect of Thermal Comfort in Nigeria

A Perspective of the Diurnal Aspect of Thermal Comfort in Nigeria

This study has examined the thermal comfort in Nigeria and the responses to thermal stress. The two hypotheses suggested for the study (that Nigeria is thermally comfortable, and that available coping strategies are sufficient to cope with thermal stress) are rejected. The study showed that thermal stress will increase in Nigeria as urba- nization, population and the global temperature increase (although the condition varies seasonally and spatially), and that climate education is largely low among Nigerians. Majority of the respondents lack indigenous ap- proach, and they preferred no precautionary solution to cope with extreme climate other than “prayers”. The general perception of the respondents on climate issues was beclouded by religious or ignorant sentiments. The results of this investigation suggest that efficient coping strategies for thermal stress are generally lacking; being limited by poor education, financial capacity and inadequate government commitment to cater for the health ef- fects of extreme climate conditions in poor communities (which incidentally comprises more than half of the Nigerian population [30]. The study concludes that Nigeria, which exemplifies many developing countries, is not yet prepared for the effect of future climate change. The study therefore recommends climate education (with effects of extreme conditions and coping strategies) at all levels of Nigerian education system, improved health schemes for climate-related and improved greening of the urban environment. Indigenous approaches to enhancing adaptation to and coping with thermal stress should also be encouraged.
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Future of thermal comfort in an energy constrained world

Future of thermal comfort in an energy constrained world

Law 2012 The Future of Thermal Comfort in an Energy-Constrained World It is worth mentioning here, that air conditioning can allow people to continue to work effectively in hot weather an[r]

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Personalized Thermal Comfort Model with Decision Tree

Personalized Thermal Comfort Model with Decision Tree

DOI: 10.4236/ica.2019.104012 169 Intelligent Control and Automation the maximum number of occupants during the peak period. However, the fixed schedule is not good enough since they cannot reflect the dynamic situations and may result in inefficiency of HVAC operations. Therefore, the usage of res- ponsive HVAC operations with real-time occupant related information is ne- cessary and it is able to improve building performances, including energy sav- ings and occupant comfort level. Lu et al. proposed the dynamic HVAC opera- tions based on the number of occupants by occupant recognition with YOLO and taking both energy efficiency and thermal comfort into account and con- ducted an energy simulation to show the energy savings with the real-time oc- cupant estimation system [1]. In addition, Bing Dong set up a large-scale sensor network to implement a nonlinear model predictive control [2]. Moreover, Zhao has developed and demonstrated the concept of Design-Build-Operate Energy Information Modeling (DBO-EIM) infrastructure, which involves occu- pant-oriented predictive building control for reducing energy consumption and maintaining occupant thermal comfort [3]. However, most of studies on dy- namic HVAC operations apply static thermal comfort model into the control logics, which cannot represent dynamic conditions in the real built environment.
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Thermal comfort survey in office buildings in Bandung, Indonesia

Thermal comfort survey in office buildings in Bandung, Indonesia

The comfort state of office building’s occupants is crucial since its related to the worker’s productivity. This comfort temperature of people from tropical climate might be different from temperate climate area. This study aimed to investigate thermal comfort and adaptive behaviour of occupants in office buildings with different ventilation modes: air-conditioned, mixed-mode, and free running. On February and March 2015, approximately 400 responses has been obtained through field surveys in three office buildings Bandung, Indonesia. The results has shown quite different comfort range between occupants in three ventilation modes: 24.7 o C, 26.3 o C, and 27.5 o C operative comfort temperature for FR, CL, and MM accordingly.
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A Conceptual Review on Residential Thermal Comfort in the Humid Tropics

A Conceptual Review on Residential Thermal Comfort in the Humid Tropics

Although the adaptive model has been recognised by ASHRAE 55 standard since 2004, there are limited worldwide publications for external validation of the model, though some investigations carried out mostly by expert in the field have been found in reliable publications. Some supported and others argued about the model limitation. Fanger and Tofum [6] admitted earlier that the adaptive model is quite good in the indoor thermal comfort prediction for non air-conditioned buildings but it was considered too simple to be adequate. The authors stated that the adaptive model is a regression equation which ignores many important parameters that change according to the indoor environment and personal parameters. The authors raised also an important question about the model in the future when the occupants may either change their clothing insulation or their activity pattern.
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The effect of pavement characteristics on pedestrians' thermal comfort in Toronto

The effect of pavement characteristics on pedestrians' thermal comfort in Toronto

Urban heat island (UHI) has proved to have an important effect in urban microclimate of large cities. In particular, the materials used for the pavements of urban spaces and sidewalks affect pedestrians’ comfort significantly. Dark materials store solar radiation during the day and re-radiate it overnight. Reversely, cool materials, given their high albedo, are often proposed for mitigating UHI issues. This paper focuses on the effect on the outdoor thermal comfort of different materials in a main urban square in Toronto. The study is performed at the neighborhood scale, using the high resolution software ENVI-met. Simulations done for a summer heat wave in 2015 allowed to predict the maximum effect of pavements with surfaces having different albedo. The physiological equivalent temperature (PET) is used to assess the pedestrians’ thermal comfort. The results show the relative effectiveness of different pavement materials. In particular, thermal comfort evaluations are reported to assess the microclimate benefits of bright marbles over black granites.
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Outdoor Universal Thermal Comfort Index Climatology for Alaska

Outdoor Universal Thermal Comfort Index Climatology for Alaska

Data from 456 surface meteorological sites in Alaska, eastern Russia and northwest Canada for 1979-2017 were used to model hourly universal ther- mal comfort indices (UTCIs) under consideration of Alaska-appropriate clothing. The results served to determine a high-resolution climatology of thermal comfort levels for Alaska at various temporal and spatial scales as well as the frequency of thermal stress levels. On 1979-2017 average, various degrees of cold stress occurred with highest percentage on the Alaska West Coast and along the Arctic Ocean. In the continental and Inside Passage re- gion, no thermal stress had the highest percentage of occurrence. In Interior Alaska, both strong heat and extreme cold stress occurred occasionally. At most sites and in all Alaska Köppen-Geiger bio-climate regions, the absolute range between monthly means of daily minimum and maximum UTCIs was larger than that of monthly means of daily minimum and maximum air tem- peratures. Major contributors to thermal discomfort (shortwave radiation, air temperature, moisture, wind speed) varied among bio-climate regions and in the diurnal and annual courses.
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Land Use and Thermal Comfort in the County of Ourinhos, SP

Land Use and Thermal Comfort in the County of Ourinhos, SP

This study aims to analyze the thermal comfort in urban areas for different land uses. The ENVI- met microclimatic model has been used for urban boundary layer simulation, providing the fol- lowing thermal comfort indexes: PMV (Predicted Mean Vote) and PPD (Predicted Percentage of Dissatisfaction). The chosen area covers the central area in the city of Ourinhos, located in sou- theastern Brazilian city, with subtropical climate. Four simulations were accomplished: an area with real buildings and vegetation on site, a “grassy” area where buildings have been replaced by grass in the central area, another grassy area, known as “grass/tree”, with additional trees in, and a final area called “Park” also grassy, where trees were added all over the area. The structures which showed thermal comfort within the ISO 7730 standards were the grassy area with no trees at 9 a.m., and a paved area, as well as the park area at 3 p.m. Other situations have presented val- ues of PMV and PPD off the limits required by the rules; they were very close to those values. The only point that presented a far cry from the comfort required was the spot in the asphalt at 9 a.m. The other situations showed PMV and PPD values not far from the limits of comfort. Only the point on the asphalt showed values far from the limit of comfort at 9 a.m.
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Thermal Comfort Of A Typical Office Building A Parametric Investigation

Thermal Comfort Of A Typical Office Building A Parametric Investigation

a computer. As explained by Chen (2009), about 70% of the researchers who study ventilation performance choose to use CFD in simulating the flow and temperature distribution in a building. Most of the indoor environment designs are getting more complicated and CFD comes in handy to predict the indoor thermal comfort.

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