scholarly journals A Review of Thermal Comfort Applied in Bus Cabin Environments

2020 ◽  
Vol 10 (23) ◽  
pp. 8648
Author(s):  
Matheus das Neves Almeida ◽  
Antonio Augusto de Paula Xavier ◽  
Ariel Orlei Michaloski
Keyword(s):  
Thermal Comfort ◽  
Thermal Sensation ◽  
Co2 Concentration ◽  
Indoor Environments ◽  
Air Velocity ◽  
Research Papers ◽  
Current State ◽  
Energy Economy ◽  
Standard Models ◽  
The Impact

As of 2020, it has been 50 years since the publication of Fanger’s predictive model of thermal comfort that was designed for indoor environments and attention worldwide is directed at the COVID-19 pandemic and discussions around recommendations for these indoor environments. In this context, many environments and their occupants will suffer consequences related to thermal comfort due to the necessary indoor air changes. In bus cabins, the impact might be even greater, seeing that they are responsible for the mass transportation of people. Thus, this paper intends to review the studies on thermal comfort that analyzed bus cabin environments. It adapts the PRISMA methodology and, as a result, it includes 22 research papers published in journals. Among those, 73% focused on approaching the occupants’ thermal sensation, followed by fuel/energy economy (18%), and driver productivity (9%). The current state-of-the-art indicates that air temperature and air velocity were the parameters most employed by the included studies, but eight papers analyzed all six parameters of the standard models of thermal comfort. The most employed model of thermal comfort was Fanger’s, but there has not been an investigation that assesses its consistency in predicting the occupants’ thermal sensation in the explored environment. Nevertheless, the analyzed studies recommended constant air change inside closed buses or keeping them open to minimize adverse effects on the occupants’ health, especially due to airborne diseases and CO2 concentration possibly being a suitable indicator to identify the need for air change.

scholarly journals Thermal comfort in the low energy building - validation and modification of the Fanger model

2021 ◽  
Vol 246 ◽  
pp. 15003
Author(s):  
Natalia Krawczyk
Keyword(s):  
Thermal Comfort ◽  
Indoor Air ◽  
Thermal Sensation ◽  
Carbon Dioxide Concentration ◽  
Low Energy ◽  
Air Velocity ◽  
University Of Technology ◽  
Calculation Results ◽  
Thermal Comfort Model ◽  
The Impact

Nowadays, we spend most of our time inside buildings. Thus, ensuring adequate thermal comfort is an important issue. The paper discusses the issue of thermal comfort assessment in the intelligent low energy building “Energis” of Kielce University of Technology (Poland). The tests conducted in a selected lecture theater focused on collecting anonymous questionnaires containing thermal sensation and air quality votes of the respondents as well as performing measurements of indoor air parameters (air and globe temperatures, relative humidity, air velocity and CO2 concentration). Based on the obtained data a comparison has been done between the actual sensation votes of the volunteers and the calculation results performed with the Fanger thermal comfort model. Two indices have been considered in the paper: PMV (Predicted Mean Vote) and PPD (Predicted Percentage Dissatisfied). A modification of the model has also been proposed, which considers the impact of the carbon dioxide concentration on thermal comfort.

scholarly journals Determination of Thermal Comfort in Indoor Sport Facilities Located in Moderate Environments: An Overview

Atmosphere ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 769 ◽  
Author(s):  
Fabio Fantozzi ◽  
Giulia Lamberti
Keyword(s):  
Thermal Comfort ◽  
Thermal Environment ◽  
Thermal Sensation ◽  
Future Research ◽  
Indoor Environmental Quality ◽  
Indoor Environments ◽  
Major Question ◽  
Sport Practice ◽  
Sport Facilities

In previous years, providing comfort in indoor environments has become a major question for researchers. Thus, indoor environmental quality (IEQ)—concerning the aspects of air quality, thermal comfort, visual and acoustical quality—assumed a crucial role. Considering sport facilities, the evaluation of the thermal environment is one of the main issues that should be faced, as it may interfere with athletes’ performance and health. Thus, the necessity of a review comprehending the existing knowledge regarding the evaluation of the thermal environment and its application to sport facilities becomes increasingly relevant. This paper has the purpose to consolidate the aspects related to thermal comfort and their application to sport practice, through a deep study concerning the engineering, physiological, and psychological approaches to thermal comfort, a review of the main standards on the topic and an analysis of the methodologies and the models used by researchers to determine the thermal sensation of sport facilities’ occupants. Therefore, this review provides the basis for future research on the determination of thermal comfort in indoor sport facilities located in moderate environments.

The effect of correlated colour temperature of lighting on thermal sensation and thermal comfort in a simulated indoor workplace

2016 ◽  
Vol 27 (3) ◽  
pp. 308-316 ◽  
Author(s):  
Rupak R Baniya ◽  
Eino Tetri ◽  
Jukka Virtanen ◽  
Liisa Halonen
Keyword(s):  
Thermal Comfort ◽  
Room Temperature ◽  
Thermal Sensation ◽  
Light Emitting Diode ◽  
Air Velocity ◽  
Light Emitting ◽  
Colour Temperature ◽  
Test Room ◽  
Illuminance Level ◽  
Colour Rendering

The ‘hue-heat’ hypothesis states that an environment which has wavelengths predominantly toward the red end of the visual spectrum feels ‘warm’ and one with wavelengths mainly toward the blue end feels ‘cool’. In order to test the hypothesis and to study the impacts of the correlated colour temperature of a light source on thermal sensation and thermal comfort, a study was conducted in a test room illuminated with an Light Emitting Diode (LED) lighting system with an adjustable correlated colour temperature where air temperature, air velocity, and relative humidity were kept constant. The correlated colour temperature of lighting inside the test room was changed gradually while keeping the colour rendering index values greater than 90, an illuminance level of 500 lx, and chromaticity difference (Duv) values within the limits of ±0.005. Sixteen study subjects were exposed to a ‘high room temperature’ (25℃) and a ‘low room temperature’ (20℃) on different days. The subjects were adapted to low correlated colour temperature (2700 K), medium correlated colour temperature (4000 K), and high correlated colour temperature (6200 K) lighting for 10 min and subsequently completed the questionnaire about their thermal comfort and thermal sensation. The results of this survey did not provide support for the hue-heat hypothesis and indicated that people felt thermally more comfortable in an indoor workplace at the correlated colour temperature of 4000 K than at the correlated colour temperature of 2700 K or 6200 K.

A Data-Driven Thermal Sensation Model Based Predictive Controller for Indoor Thermal Comfort and Energy Optimization

2014 ◽  
Author(s):  
Xiao Chen ◽  
Qian Wang
Keyword(s):  
Thermal Comfort ◽  
Thermal Sensation ◽  
Energy Optimization ◽  
Data Driven ◽  
Air Velocity ◽  
Comfort Index ◽  
Indoor Thermal Comfort ◽  
Occupant Feedback ◽  
Predictive Controller ◽  
Radiant Temperature

This paper proposes a model predictive controller (MPC) using a data-driven thermal sensation model for indoor thermal comfort and energy optimization. The uniqueness of this empirical thermal sensation model lies in that it uses feedback from occupants (occupant actual votes) to improve the accuracy of model prediction. We evaluated the performance of our controller by comparing it with other MPC controllers developed using the Predicted Mean Vote (PMV) model as thermal comfort index. The simulation results demonstrate that in general our controller achieves a comparable level of energy consumption and comfort while eases the computation demand posed by using the PMV model in the MPC formulation. It is also worth pointing out that since we assume that our controller receives occupant feedback (votes) on thermal comfort, we do not need to monitor the parameters such as relative humidity, air velocity, mean radiant temperature and occupant clothing level changes which are necessary in the computation of PMV index. Furthermore simulations show that in cases where occupants’ actual sensation votes might deviate from the PMV predictions (i.e., a bias associated with PMV), our controller has the potential to outperform the PMV based MPC controller by providing a better indoor thermal comfort.

scholarly journals Thermal comfort, thermal sensation and skin temperature measurements using demand-controlled ventilation for individual cooling

2020 ◽  
Vol 172 ◽  
pp. 06001
Author(s):  
Håkon Solberg ◽  
Kari Thunshelle ◽  
Peter Schild
Keyword(s):  
Thermal Comfort ◽  
Skin Temperature ◽  
Energy Demand ◽  
Thermal Sensation ◽  
Air Velocity ◽  
Climate Chamber ◽  
Biometric Data ◽  
Ongoing Research ◽  
Demand Controlled Ventilation ◽  
The Relationship

An increasing part of modern building's energy demand is due to cooling. An ongoing research project investigates the possibility to reduce the energy consumption from cooling by utilizing an individually controlled active ventilation diffuser mounted in the ceiling. This study looks at thermal sensation and thermal comfort for 21 test persons exposed to an innovative user controlled active ventilation valve, in a steady and thermally uniform climate chamber. Furthermore, the relationship between biometric data from the test persons skin temperature and sweat, and the test persons thermal sensation scores has been investigated. Each test person was exposed to three different room temperatures in the climate chamber, 24°C, 26°C and 28°C respectively, to simulate typical hot summer conditions in an office in Norway. At a room temperature of 26°C it was possible to achieve acceptable thermal comfort for most test persons with this solution, but higher air velocity than 0.75 m/s around the test persons bodies at room temperatures of 28°C is required to ensure satisfactory thermal comfort.

A Fan in Winter

1983 ◽  
Vol 27 (8) ◽  
pp. 742-745 ◽  
Author(s):  
Frederick H. Rohles ◽  
Byron W. Jones
Keyword(s):  
Thermal Comfort ◽  
Thermal Sensation ◽  
Test Chamber ◽  
Air Velocity ◽  
Subjective Responses ◽  
Human Thermal Comfort ◽  
Significant Difference ◽  
Maximum Period ◽  
Air Space ◽  
Indoor Conditions

In order to determine the effect of ceiling fans on human thermal comfort under winter indoor conditions, 72 subjects (36 men and 36 women) were exposed to 21°C/40% rh for 3 hours while experiencing still air conditions (0.08 m/s) and air velocities where a ceiling fan was operating in a upward-thrust mode at 2 velocities (0.18 and 0.28 m/s). Two subjective responses, thermal sensation and thermal comfort, were recorded each half hour. The results showed that after 2 hours, which may be assumed to be the maximum period of time that an individual would sit without getting up, the subjects recorded (1) the same neutral thermal sensation when the fan was at the still air condition (0.0 8 m/s) as when it was producing an air velocity of 0.18 m/s, (2) a slightly cool thermal sensation at a velocity of 0.28 m/s and (3) no significant difference in thermal comfort between still air (0.08 m/s) and velocities up to 0.28 m/s. It was concluded that the air movement created by operating the ceiling fan under winter conditions does not contribute to nor detract from human comfort nor did it produce any response resembling wind chill. These results were considered conservative since no temperature stratification existed in the test chamber air space which would be expected in exist in a conventionally heated room space.

Cooling with Box Fans

1982 ◽  
Vol 26 (2) ◽  
pp. 123-127
Author(s):  
Eric Rosen ◽  
Stephan Konz
Keyword(s):  
Thermal Comfort ◽  
Room Temperature ◽  
Thermal Sensation ◽  
Office Work ◽  
Air Velocity ◽  
Preferred Direction ◽  
The Subject ◽  
Paper And Pencil ◽  
C 78

Two experiments are described. Experiment 1 investigated the preferred direction of air upon a person. Forty males sat in front of a box fan in 12 different seating orientations (30° increments). Air velocity was .7 m/s (140 ft/min); room temperature was 28 C (82 F) with 40% rh. The preference was bimodal with the most preferred directions from the front or the rear; velocities from the side were less preferred. Experiment 2 investigated 3 velocities (“still air”, .8 m/s (160 ft/min) and 1.3 m/s (260 ft/min)) at 3 temperatures (25.6, 27.8 and 30 C; 78, 82, 86 F). Eight subjects each spent three hours in each of the 9 conditions. Clothing was standardized at about .5 clo. Subjects did a paper and pencil task (maze) and a peg into hole task. Thermal comfort and thermal sensation ballots were completed every 15 min. At the end of 150 min., they moved their chair in relation to the fan so as to select their preferred velocity. The current recommended ceiling of .8 m/s for sedentary office work is too low as the subject-selected velocity was .7 m/s at 25.6 C, was 1.0 m/s at 27.8 C and was 1.2 m/s at 30 C. These results were confirmed by the thermal comfort and thermal sensation ballots. Depending on the criterion used, for seated sedentary work in warm conditions, every 0.1 m/s (20 ft/min) increase in air velocity offsets approximately a 0.4 C (0.7 F) increase in temperature (0.7 < V < 1.2 m/s).

scholarly journals Experimental and statistical survey on local thermal comfort impact on working productivity loss in university classrooms

2019 ◽  
Vol 23 (1) ◽  
pp. 379-392 ◽  
Author(s):  
Tamara Bajc ◽  
Milos Banjac ◽  
Maja Todorovic ◽  
Zana Stevanovic
Keyword(s):  
Thermal Comfort ◽  
Productivity Loss ◽  
Thermal Conditions ◽  
Co2 Concentration ◽  
Heating System ◽  
Indoor Environmental Quality ◽  
Personal Factor ◽  
Predicted Mean Vote ◽  
Local Thermal Comfort ◽  
The Impact

The paper presents an experimental analysis of the relationship between local thermal comfort and productivity loss in classrooms. The experimental investigation was performed in a real university classroom during the winter semester in city of Belgrade. Measurements were taken for four scenarios, with different indoor comfort conditions. Variations were made by setting the central heating system on/off, adding an additional heat source to provoke higher indoor temperatures, and measuring the radiant asymmetry impact. Innovative questionnaires were developed especially for the research, in order to investigate students? subjective feelings about local thermal comfort and indoor environmental quality. Local predicted mean vote and predicted percentage dissatisfied indices were calculated using data measured in situ. The results were compared to existing models recommended in literature and European and ASHRAE standards. Student productivity was evaluated using novel tests, designed to fit the purposes of the research. Surveys were conducted for 19 days under different thermal conditions, during lectures in a real classroom, using a sample of 240 productivity test results in total. Using the measured data, new correlations between the predicted mean vote, CO2, personal factor and productivity loss were developed. The research findings imply that local thermal comfort is an important factor that can impact productivity, but the impact of the personal factor is of tremendous importance, together with CO2 concentration in the classroom.

scholarly journals CLIMATOLOGY OF THE HUMAN THERMAL COMFORT ON SÃO PAULO METROPOLITAN AREA, BRAZIL: INDOORS AND OUTDOORS

2015 ◽  
Vol 33 (2) ◽  
Author(s):  
Anderson Spohr Nedel ◽  
Fábio Luiz Teixeira Gonçalves ◽  
Celso Macedo Junior ◽  
Maria Regina Alves Cardoso
Keyword(s):  
Thermal Comfort ◽  
Thermal Sensation ◽  
Sao Paulo ◽  
Winter Period ◽  
Indoor Environments ◽  
São Paulo ◽  
Human Thermal Comfort ◽  
Outdoor Environments ◽  
External Conditions ◽  
The Relationship

ABSTRACT. The purpose of this study is to carry out a climatological analysis of human thermal comfort in the São Paulo city, Brazil, for outdoor and indoor environments, applying different indexes of thermal comfort in order to assess which of them represent best the weather characteristics of the São Paulo city. The relationship between these indexes and the seasons (fall, winter, spring, summer) was investigated in the period from 1980 to 2005, for outdoor environments, and during 2005, for the indoor environments. The results showed that the most appropriate index for São Paulo, both for internal and external conditions was the Effective Temperature Index (ET) as it has a broad classification and can provide appropriate representations of the region’s comfort. According to this index, the mornings during summer in the outdoor environments showed mild discomfort by cold, and the afternoons were comfortable. In winter, there was thermal stress by cold during the mornings and a slight discomfort by cold during the afternoons. For indoor environments in the summer, most of the houses presented comfortable mornings, and afternoons with discomfort in relation to the heat, while in the winter, period proved to be uncomfortable and stressful due to cold and the afternoonscharacterized themselves as comfortable.Keywords: thermal sensation, biometeorology, biometeorological indexes.RESUMO. O objetivo deste estudo é realizar uma análise climatológica do conforto térmico humano na cidade de São Paulo, Brasil, para ambientes externos e internos, aplicando diferentes índices de conforto térmico, a fim de avaliar qual deles melhor representa as características climáticas da cidade de São Paulo. A relação entre esses índices e as estações do ano (outono, inverno, primavera, verão) foi investigada no período compreendido entre 1980 e 2005 para os ambientes externos, como também durante o ano de 2005 para os ambientes internos. Os resultados mostraram que o índice de Temperatura Efetiva (TE) é o mais apropriado para São Paulo, tanto para condições internas quanto externas, pois este possui uma classificação ampla e pode fornecer representações adequadas do conforto da região. Segundo esse índice, as manhãs, durante o verão nos ambientes externos, apresentaram leve desconforto por frio, e as tardes estiveram confortáveis. Já no inverno, observou-se estresse térmico por frio durante as manhãs e um ligeiro desconforto por frio no período das tardes. Para os ambientes internos, a maioria das casas apresentou no verão manhãs confortáveis e tardes com desconforto em relação ao calor; já no inverno, o período das manhã mostrou-se desconfortável e estressante devido ao frio e as tardes caracterizaram-se como confortáveis.Palavras-chave: sensação térmica, biometeorologia, índices biometeorológicos.

scholarly journals Enhancement of Thermal Comfort Inside the Kitchen of Non-Airconditioned Railway Pantry Car

2021 ◽  
Vol 39 (1) ◽  
pp. 275-291
Author(s):  
Md Sarfaraz Alam ◽  
Urmi Ravindra Salve
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
Thermal Environment ◽  
Thermal Sensation ◽  
Ventilation System ◽  
Comfort Level ◽  
Air Velocity ◽  
Sustainable Improvement ◽  
Study Results ◽  
Air Ventilation

There are ample literature studies available, focusing on hot-humid built environment, which have achieved an increase in thermal comfort conditions by proper installation of ventilation-systems. The present thermal comfort study has been carried out in the kitchen environment of a non-air-conditioned railway pantry car in Indian Railways. The purpose is to enhance thermal comfort level under the currently applied ventilation system inside the kitchen of pantry car by determining the standard effective temperature (SET) index. During the summer and winter seasons, a field study was carried out to obtain the value of air temperature, globe temperature, relative humidity, and air velocity inside the pantry car for estimation of the SET index. A computational fluid dynamics (CFD) analysis was used to obtain a better-modified case model of the pantry car kitchen for the improvement of thermal comfort. The design interventions for the pantry car kitchen were created, with emphasis on increasing energy efficiency based on low-power consumption air ventilation system. The study results indicated that, modified case-I model has a better ventilation design concept as compare to the existing and other models, which increased the air velocity and significantly decreased the air temperature inside the kitchen of pantry car at all cooking periods. A value of SET (28.6–30℃) was found with a comfortable thermal sensation within all cooking periods, which is better for the pantry car workers. This finding suggests a sustainable improvement in the thermal environment of the "non-air-conditioned" pantry car kitchen in the Indian Railways, which can be applied immediately.

Sign in / Sign up

Export Citation Format

Share Document