Overall and thermal comfort under different temperature, noise, and vibration exposures

On Structural Health Monitoring of Wind Turbine Blades

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.569-570.628 ◽

2013 ◽

Vol 569-570 ◽

pp. 628-635 ◽

Cited By ~ 6

Author(s):

Jonas Falk Skov ◽

Martin Dalgaard Ulriksen ◽

Kristoffer Ahrens Dickow ◽

Poul Henning Kirkegaard ◽

Lars Damkilde

Keyword(s):

Structural Health Monitoring ◽

Wind Turbine ◽

Health Monitoring ◽

Damage Identification ◽

State Of The Art ◽

Turbine Blades ◽

Wind Turbine Blades ◽

Noise And Vibration ◽

Structural Health ◽

Temperature Noise

The aim of the present paper is to provide a state-of-the-art outline of structural health monitoring (SHM) techniques, utilizing temperature, noise and vibration, for wind turbine blades, and subsequently perform a typology on the basis of the typical 4 damage identification levels in SHM. Before presenting the state-of-the-art outline, descriptions of structural damages typically occurring in wind turbine blades are provided along with a brief description of the 4 damage identification levels.

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Analysis of the Influence of Age on Human Thermal Comfort

ICCREM 2020 ◽

10.1061/9780784483237.020 ◽

2020 ◽

Author(s):

Boshuai Dong ◽

Chunjing Shang ◽

Ming Tong ◽

Jianhong Cai

Keyword(s):

Thermal Comfort ◽

Human Thermal Comfort

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Influence of trees on the energy consumption of a social housing in mid-western Brazil

WEENTECH Proceedings in Energy ◽

10.32438/wpe.4819 ◽

2019 ◽

pp. 53-65

Author(s):

Renata Domingos ◽

Emeli Guarda ◽

Elaise Gabriel ◽

João Sanches

Keyword(s):

Energy Consumption ◽

Solar Radiation ◽

Thermal Comfort ◽

Air Conditioning ◽

Computational Simulation ◽

Building Energy ◽

General Idea ◽

Heat Island ◽

Study Region ◽

Ample Evidence

In the last decades, many studies have shown ample evidence that the existence of trees and vegetation around buildings can contribute to reduce the demand for energy by cooling and heating. The use of green areas in the urban environment as an effective strategy in reducing the cooling load of buildings has attracted much attention, though there is a lack of quantitative actions to apply the general idea to a specific building or location. Due to the large-scale construction of high buildings, large amounts of solar radiation are reflected and stored in the canyons of the streets. This causes higher air temperature and surface temperature in city areas compared to the rural environment and, consequently, deteriorates the urban heat island effect. The constant high temperatures lead to more air conditioning demand time, which results in a significant increase in building energy consumption. In general, the shade of the trees reduces the building energy demand for air conditioning, reducing solar radiation on the walls and roofs. The increase of urban green spaces has been extensively accepted as effective in mitigating the effects of heat island and reducing energy use in buildings. However, by influencing temperatures, especially extreme, it is likely that trees also affect human health, an important economic variable of interest. Since human behavior has a major influence on maintaining environmental quality, today's urban problems such as air and water pollution, floods, excessive noise, cause serious damage to the physical and mental health of the population. By minimizing these problems, vegetation (especially trees) is generally known to provide a range of ecosystem services such as rainwater reduction, air pollution mitigation, noise reduction, etc. This study focuses on the functions of temperature regulation, improvement of external thermal comfort and cooling energy reduction, so it aims to evaluate the influence of trees on the energy consumption of a house in the mid-western Brazil, located at latitude 15 ° S, in the center of South America. The methodology adopted was computer simulation, analyzing two scenarios that deal with issues such as the influence of vegetation and tree shade on the energy consumption of a building. In this way, the methodological procedures were divided into three stages: climatic contextualization of the study region; definition of a basic dwelling, of the thermophysical properties; computational simulation for quantification of energy consumption for the four facade orientations. The results show that the façades orientated to north, east and south, without the insertion of arboreal shading, obtained higher values of annual energy consumption. With the adoption of shading, the facades obtained a consumption reduction of around 7,4%. It is concluded that shading vegetation can bring significant climatic contribution to the interior of built environments and, consequently, reduction in energy consumption, promoting improvements in the thermal comfort conditions of users.

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Evaluation of thermal comfort in a large hospital using a questionnaire and measurement

Journal of Odor and Indoor Environment ◽

10.15250/joie.2018.17.2.174 ◽

2018 ◽

Vol 17 (2) ◽

pp. 174-181

Author(s):

Jonghyun Ji ◽

Seongmin Jo ◽

Jongil Bang ◽

Minki Sung

Keyword(s):

Thermal Comfort ◽

Large Hospital

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Characterisation of the Humming-Type Noise and Vibration of the Automotive HVAC System

International Journal of Automotive and Mechanical Engineering ◽

10.15282/ijame.16.2.2019.12.0499 ◽

2019 ◽

Vol 16 (2) ◽

pp. 6634-6648

Author(s):

A. Z. A. Mazlan ◽

M. H. A. Satar ◽

M. H. Hamdan ◽

M. S. Md. Isa ◽

S. Man ◽

...

Keyword(s):

Vibration Characteristics ◽

Operating Conditions ◽

Hvac System ◽

Frequency Range ◽

Noise And Vibration ◽

Power Steering ◽

Pump Compressor

The automotive heating and ventilating air condition (HVAC) system, when vibrating, can generate various types of noises such as humming, hissing, clicking and air-rushes. These noises can be characterised to determine their root causes. In this study, the humming-type noise is taken into consideration whereby the noise and vibration characteristics are measured from various HVAC components such as power steering pump, compressor and air conditional pipe. Four types of measurement sensors were used in this study - tachometer for rpm tracking; accelerometer for the vibration microphone for the noise; and sound camera for the visualization measurement. Two types of operating conditions were taken into consideration - they were “idle” (850 rpm) and “running” (850-1400 rpm) conditions. A constant blower speed was applied for both conditions. The result shows that the humming noises can be determined at the frequency range of 300-350 Hz and 150-250 Hz for both idle and running conditions, respectively. The vibration of the power steering pump shows the worst acceleration of 1.8 m/s2 at the frequency range of 150-250 Hz, compared to the compressor and air conditional pipe. This result was validated with the 3D colour order and sound camera analyses, in which the humming noise colour mapping shows dominance in this frequency range.

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