Differents Methods to Estimate the Mean Radiant Temperature in an Urban Canyon

2013 ◽  
Vol 650 ◽  
pp. 647-651 ◽  
Author(s):  
R. de Lieto Vollaro ◽  
A. Vallati ◽  
S. Bottillo
Keyword(s):  
Human Body ◽  
Street Canyon ◽  
The Other ◽  
Radiation Environment ◽  
Mean Radiant Temperature ◽  
Radiation Fluxes ◽  
Human Energy ◽  
Environment Simulation ◽  
The Mean ◽  
Radiant Temperature

The mean radiant temperature is one of the meteorological key parameters governing human energy balance and the thermal comfort of human body. This variable can be considered as the sum of all direct and reflected radiation fluxes to which the human body is exposed. After the basics of the Tmrt calculation a comparison between two methods suitable for obtaining Tmrt in a street canyon will be presented. One of the discussed methods of obtaining Tmrt is based on the utilization of a globe thermometer. The other method is the radiation environment simulation through three PC software (RayMan, ENVI-met and SOLWEIG).

scholarly journals The most problematic variable in the course of human-biometeorological comfort assessment — the mean radiant temperature

2011 ◽  
Vol 3 (1) ◽  
Author(s):  
Noémi Kántor ◽  
János Unger
Keyword(s):  
Thermal Comfort ◽  
Short Wave ◽  
Urban Environments ◽  
Outdoor Thermal Comfort ◽  
Radiation Environment ◽  
Wave Radiation ◽  
Mean Radiant Temperature ◽  
Radiation Fluxes ◽  
The Mean ◽  
Radiant Temperature

AbstractThis paper gives a review on the topic of the mean radiant temperature Tmrt, the most important parameter influencing outdoor thermal comfort during sunny conditions. Tmrt summarizes all short wave and long wave radiation fluxes reaching the human body, which can be very complex (variable in spatial and also in temporal manner) in urban settings. Thermal comfort researchers and urban planners need easy and sound methodological approaches to assess Tmrt. After the basics of the Tmrt calculation some of the methods suitable for obtaining Tmrt also in urban environments will be presented.. Two of the discussed methods are based on instruments which measure the radiation fluxes integral (globe thermometer, pyranometer-pyrgeometer combination), and three of the methods are based on modelling the radiation environment with PC software (RayMan, ENVI-met and SOLWEIG).

scholarly journals The effect of radiation from the surroundings on subjective impressions of freshness

1949 ◽  
Vol 47 (3) ◽  
pp. 288-296 ◽  
Author(s):  
A. F. Munro ◽  
F. A. Chrenko
Keyword(s):  
Relative Humidity ◽  
The Other ◽  
Research Station ◽  
Mean Radiant Temperature ◽  
Equivalent Temperature ◽  
Building Research ◽  
The Mean ◽  
The Difference ◽  
Effects Of Radiation ◽  
Radiant Temperature

The effects of radiation from the surroundings on the impressions of freshness of 106 men and 39 women members of the staff of the Building Research Station were investigated during the first 6 months of 1948. Subjects were exposed to three types of environment: (1) where the walls were cooler than the air, (2) where the walls and air were at the same temperature, and (3) where the walls were warmer than the air. The tests were carried out in calm air.It was found that the difference between the mean radiant temperature and the air temperature affected freshness impressions, but the effect was relatively slight. Environments which felt cool tended to feel fresh, yet a rise in the mean radiant temperature—which would increase the warmth of the environment—tended to produce an impression of greater freshness. At a given equivalent temperature, environments with the surroundings warmer than the air were found to be definitely fresher than cold- and neutral-wall environments. This was thought to be mainly due to the fact that the humidity of the air in the warm-wall environment was lower than that in the other two environments. Changes in humidity insufficient to affect sensations of warmth affect impressions of freshness. Under the conditions of these experiments, and to keep freshness impressions constant, a rise of 1° F. in the temperature of calm air must be compensated by a fall of about 5% in the relative humidity.The subjects had a distinct preference for the warm-wall environment; 73% of them found it pleasanter than either the cold- or the neutral-wall environment.Freshness impressions are considered to be related to transient fluctuations in the rate of heat loss from the head.

scholarly journals SIMULATION OF THE INFLUENCE OF VEGETATION ON MICROCLIMATE AND THERMAL COMFORT IN THE CITY OF SÃO PAULO

2019 ◽  
Vol 3 (2) ◽  
pp. 1 ◽  
Author(s):  
Jörg Spangenberg ◽  
Paula Shinzato ◽  
Erik Johansson ◽  
Denise Duarte
Keyword(s):  
Thermal Comfort ◽  
Street Canyon ◽  
Sao Paulo ◽  
City Centre ◽  
São Paulo ◽  
Mean Radiant Temperature ◽  
Speed Up ◽  
The Mean ◽  
Radiant Temperature ◽  
The City

The microclimates of a park, a square and a street canyon were measured on a summer day in the city centre of São Paulo, Brazil. The field monitoring showed that the park was up to 2°C cooler than the square and the canyon. The effect of adding shading trees to the street canyon was simulated for the same day using the numerical model ENVI-met. The simulations showed that incorporating street trees in the urban canyon had a limited cooling effect on the air temperature (up to 1.1°C), but led to a significant cooling of the street surface (up to 12°C) as well as a great reduction of the mean radiant temperature at pedestrian height (up to 24°C). Although the trees lowered the wind speed up to 45% of the maximum values, the thermal comfort was improved considerably as the physiologically equivalent temperature (PET) was reduced by up to 12°C.

scholarly journals Correcting the Error in Measuring Radiation Received by a Person: Introducing Cylindrical Radiometers

Sensors ◽  
2019 ◽  
Vol 19 (23) ◽  
pp. 5085 ◽  
Author(s):  
Brown
Keyword(s):  
Vertical Cylinder ◽  
Spherical Shape ◽  
Indoor Environments ◽  
New Instrument ◽  
Human Energy ◽  
Integral Radiation ◽  
Outdoor Environments ◽  
The Mean ◽  
Radiant Temperature ◽  
New Instruments

Most human energy budget models consider a person to be approximately cylindrical in shape when estimating or measuring the amount of radiation that they receive in a given environment. Yet, the most commonly used instrument for measuring the amount of radiation received by a person is the globe thermometer. The spherical shape of this instrument was designed to be used indoors where radiation is received approximately equally from all directions. But in outdoor environments, radiation can be strongly directional, making the sphere an inappropriate shape. The international standard for measuring radiation received by a person, the Integral Radiation Measurement (IRM) method, yields a measure of the Mean Radiant Temperature (Tmrt). This method uses radiometers oriented in the four cardinal directions, plus up and down. However, this setup essentially estimates the amount of energy received by a square peg, not a cylinder. This paper identifies the errors introduced by both the sphere and the peg, and introduces a set of two new instrument that can be used to directly measure the amount of radiation received by a vertical cylinder in outdoor environments. The Cylindrical Pyranometer measures the amount of solar radiation received by a vertical cylinder, and the Cylindrical Pyrgeometer measures the amount of terrestrial radiation received. While the globe thermometer is still valid for use in indoor environments, these two new instruments should become the standard for measuring radiation received by people in outdoor environments.

scholarly journals SPUCAL_mrt as a New Model for Estimating the Mean Radiant Temperature in Arid Lands

2015 ◽  
Vol 74 ◽  
pp. 273-280 ◽  
Author(s):  
Ahriz Atef ◽  
Zemmouri Noureddine ◽  
Fezzai Soufiane
Keyword(s):  
Arid Lands ◽  
Mean Radiant Temperature ◽  
New Model ◽  
The Mean ◽  
Radiant Temperature
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