Adapting the Olgyay bioclimatic chart to assess local thermal comfort levels in urban regions

2021 ◽  
Author(s):  
Renan Hatakeyama Pontes ◽  
Mohammad K. Najjar ◽  
Ahmed W. A. Hammad ◽  
Elaine Vazquez ◽  
Assed Haddad
Keyword(s):  
Thermal Comfort ◽  
Urban Regions ◽  
Comfort Levels ◽  
Local Thermal Comfort

scholarly journals Experimental Investigation of Ventilation Performance of Different Air Distribution Systems in an Office Environment—Heating Mode

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1835 ◽  
Author(s):  
Arman Ameen ◽  
Mathias Cehlin ◽  
Ulf Larsson ◽  
Taghi Karimipanah
Keyword(s):  
Thermal Comfort ◽  
Distribution Systems ◽  
Cold Climate ◽  
Air Distribution ◽  
Temperature Pattern ◽  
Office Environment ◽  
Ventilation Effectiveness ◽  
Local Thermal Comfort ◽  
Heating Mode ◽  
Occupied Zone

A vital requirement for all-air ventilation systems are their functionality to operate both in cooling and heating mode. This article experimentally investigates two newly designed air distribution systems, corner impinging jet (CIJV) and hybrid displacement ventilation (HDV) in comparison against a mixing type air distribution system. These three different systems are examined and compared to one another to evaluate their performance based on local thermal comfort and ventilation effectiveness when operating in heating mode. The evaluated test room is an office environment with two workstations. One of the office walls, which has three windows, faces a cold climate chamber. The results show that CIJV and HDV perform similar to a mixing ventilation in terms of ventilation effectiveness close to the workstations. As for local thermal comfort evaluation, the results show a small advantage for CIJV in the occupied zone. Comparing C2-CIJV to C2-CMV the average draught rate (DR) in the occupied zone is 0.3% for C2-CIJV and 5.3% for C2-CMV with the highest difference reaching as high as 10% at the height of 1.7 m. The results indicate that these systems can perform as well as mixing ventilation when used in offices that require moderate heating. The results also show that downdraught from the windows greatly impacts on the overall airflow and temperature pattern in the room.

Heart rate variability at different thermal comfort levels

2008 ◽  
Vol 103 (3) ◽  
pp. 361-366 ◽  
Author(s):  
Weiwei Liu ◽  
Zhiwei Lian ◽  
Yuanmou Liu
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Thermal Comfort ◽  
Comfort Levels

Transient Human Thermal Comfort Response in Convective and Radiative Environments

2008 ◽  
Author(s):  
Mohamad Al-Othmani ◽  
Nesreen Ghaddar ◽  
Kamel Ghali
Keyword(s):  
Thermal Comfort ◽  
Thermal Conditions ◽  
Activity Level ◽  
Convective Heating ◽  
Convective System ◽  
Clothing Insulation ◽  
Indoor Space ◽  
Human Thermal Comfort ◽  
Walking Activity ◽  
Local Thermal Comfort

In this work, human transient thermal responses and comfort are studied in non-uniform radiant heating and convective heating environments. The focus was on a change from walking activity of human in outdoor cold environment at high clothing insulation to warm indoor environment at sedentary activity level associated with lower clothing insulation. A transient multi-segmented bioheat model sensitive to radiant asymmetry is used to compare how fast the human body approaches steady state thermal conditions in both radiative and convective warm environments. A space thermal model is integrated with the bioheat model to predict the transient changes in skin and core temperature of a person subject to change in metabolic rate and clothing insulation when entering conditioned indoor space. It was found that overall thermal comfort and neutrality were reached in 6.2 minutes in the radiative environment compared to 9.24 minutes in convective environment. The local thermal comfort of various body segments differed in their response to the convective system where it took more than 19 minutes for extremities to reach local comfort unlike the radiative system where thermal comfort was attained within 7 minutes.

scholarly journals The Importance of Standardised Data-Collection Methods in the Improvement of Thermal Comfort Assessment Models for Developing Countries in the Tropics

2019 ◽  
Vol 11 (15) ◽  
pp. 4180 ◽  
Author(s):  
Carolina Rodriguez ◽  
María Coronado ◽  
Marta D’Alessandro ◽  
Juan Medina
Keyword(s):  
Developing Countries ◽  
Data Collection ◽  
Thermal Comfort ◽  
Air Conditioning ◽  
Energy Use ◽  
Comfort Levels ◽  
Geographical Regions ◽  
Adaptive Behaviours ◽  
The Tropics ◽  
Occupant Satisfaction

Thermal comfort in the built environment is one of the most defining parameters influencing energy use, environmental quality, and occupant satisfaction. Unfortunately, there is a lack of research in this area within developing countries, which are becoming increasingly urbanised and where mechanical air conditioning demands are rising. Many of these countries are adopting thermal comfort standards such as the ASHRAE Standard 55, the EN 15251, and the ISO 7730 to regulate the use of air-conditioning; even when these standards have been widely criticised for their inadequacy within geographical regions different to the ones that they were designed for. Research suggests the need to confirm these models through further post-occupancy studies and fieldwork. Deficiencies in data collection and methodologies are thought to require particular attention to develop algorithms that can predict thermal comfort levels accurately. Comprehensive strategies considering interrelated psychological, physiological and social factors are needed. This manuscript highlights gaps of research, specifically within tropical developing countries, through the analysis of Colombia as a case study. It emphasises the importance of standardised fieldwork data and gives examples of alternative collection systems. This aims to contribute to the understanding of occupant´s adaptive behaviours and their impact on the mitigation of climate change.

scholarly journals Assessing the indoor thermal comfort of a toll station

2019 ◽  
Vol 282 ◽  
pp. 02031
Author(s):  
Ricardo M.S.F. Almeida ◽  
Eva Barreira ◽  
Sandra Soares ◽  
Ramos Nuno M.M. ◽  
Sérgio Lopes ◽  
...  
Keyword(s):  
Thermal Comfort ◽  
Indoor Environment ◽  
Thermal Sensation ◽  
Physical Parameters ◽  
Indoor Environmental Quality ◽  
Thermal Perception ◽  
Health And Wellbeing ◽  
Local Thermal Comfort ◽  
Toll Station ◽  
Global And Local

The importance of a good indoor environment for peoples’ health and wellbeing is nowadays clearly established. Besides enhancing the wellbeing of building occupants and helping decrease the occurrence of building related illness, a good indoor environment can also lead to a decrease in worker complaints and absenteeism. This paper presents the results of a three-month monitoring campaign where the thermal comfort of a toll station was evaluated, including the main room and the cabins. The physical parameters required for the assessment of both global and local thermal comfort were measured and the results were compared with the thermal perception of the occupants, which was collected through questionnaires. The indoor environmental quality in the main room was better than in the cabins and a mismatch between the PMV index and the occupants thermal sensation was identified.

Numerical analysis of local thermal comfort in a plan office under natural ventilation

2019 ◽  
Vol 29 (7) ◽  
pp. 972-986 ◽  
Author(s):  
Xiang Deng ◽  
Zijing Tan
Keyword(s):  
Thermal Comfort ◽  
Natural Ventilation ◽  
Meteorological Data ◽  
Ventilation System ◽  
Comfort Level ◽  
Open Plan ◽  
Computational Fluid Dynamics Cfd ◽  
Internal Volume ◽  
Local Thermal Comfort ◽  
Primary Focus

The utilisation of automatic controlled natural wind in office buildings to maintain indoor thermal comfort has gained wide attention in recent years. Generally, it is not necessary to ensure that the whole internal volume of a building with large open spaces meets thermal comfort requirements. Primary focus should be on occupied areas. Accordingly, the local thermal comfort in an open-plan office with automatic controlled natural ventilation system was investigated numerically and experimentally. A computational fluid dynamics (CFD)-based method was presented for indoor environment and thermal comfort prediction. Long-term in situ measurement was conducted during summer and transition seasons. The meteorological data were collected by a mini weather station located on the roof of the target building. Meanwhile, indoor air velocity, temperature, turbulence intensity and wall temperatures were recorded locally. Three thermal comfort indices, i.e. thermal stratification represented by percentage dissatisfied (PD), the extended predicted mean vote (PMVe) and draught rate were employed to evaluate the thermal comfort level of the interested areas during natural ventilation period. The numerical results revealed a risk of local thermal dissatisfaction under low outdoor temperature and strong windy conditions.

scholarly journals Evaluation of Basement's Thermal Performance Against Thermal Comfort Model at Hot-arid Climates, Case Study (Egypt)

2017 ◽  
Vol 2 (1) ◽  
pp. 24
Author(s):  
Heba Hassan Kamel ◽  
Daisuke Sumiyoshi
Keyword(s):  
Iterative Method ◽  
Thermal Comfort ◽  
Thermal Performance ◽  
High Energy ◽  
Mean Bias Error ◽  
Comfort Levels ◽  
Diurnal Range ◽  
Energy Plus ◽  
Thermal Comfort Model

Reaching thermal comfort levels in hot-arid climates is becoming more difficult nowadays without the use of high energy consuming mechanical systems. Therefore, the need to use effective passive energy design techniques such as earth-sheltered buildings is becoming greater. This paper combines researches that uses monitoring and simulations in order to evaluate basements’ thermal performance that reached thermal comfort levels without active air-conditioning systems, despite the harsh climate conditions. The case study was conducted in Al-Minya city, Egypt, which is known for its high diurnal range. The study calibrated a non-conditioned basement simulation model versus the monitored data to simulate its thermal performance. The greatest challenge was to calculate the ground temperature. To do this successfully, we used an iterative approach between packages of the basement preprocessor and Energy Plus / Design Builder until reaching a convergence. The iterative method results showed significant agreement between the measured and modeled data; with a correlation of 98 percent and errors with mean bias error and normalized root mean square error of -1.0 and 7.6 percent; respectively. On the other hand, the Energy Plus method, integrating the Xing approach, showed significantly divergent results between the simulated models versus the measured data. The calibrated model analysis evaluation, using the Fanger’s thermal comfort model, showed satisfactory results within the thermal comfort sensation range. The research results significance indicates that the precise customized detailed iterative method is essential to create the needed inputs which subsequently lead to near-to-actual outputs compared with other ground-contact simulation methods. In fact, the precise customized detailed iterative method approach may be used as a benchmark for simulators for easy and precise ground temperatures’ calculations and earth-sheltered buildings’ simulations.

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