scholarly journals Pan–Tilt IR Scanning Method for the Remote Measurement of Mean Radiant Temperatures at Multi-Location in Buildings

2021 ◽  
Vol 13 (11) ◽  
pp. 2158
Author(s):  
Dong-Seok Lee ◽  
Jae-Hun Jo
Keyword(s):  
Thermal Comfort ◽  
Thermal Environment ◽  
Radiant Heat ◽  
Cooling Systems ◽  
Ir Camera ◽  
Scanning Method ◽  
Image Frame ◽  
Heating And Cooling ◽  
The Mean ◽  
Time Evaluation

The mean radiant temperature (MRT) is an indicator for evaluating the radiant heat environment near occupants and is determined by the radiant heat exchange between the occupants and their surroundings. To control various heating and cooling systems according to the occupants’ thermal comfort, it is essential to consider MRTs in the real-time evaluation of thermal environment. This study proposes a pan–tilt infrared (IR) scanning method to estimate the MRTs at multiple occupant locations in real buildings. The angle factor was calculated by defining the specific classification criteria for dividing the entire indoor surface into sub-surfaces. The coupling IR camera and pan–tilt motor were applied to enable storing data pairs of IR thermal image frame (IR image frame) and pan–tilt angle so each surface area taken by the IR camera can have its direction information. The measurement method of the mean surface temperature using the pan–tilt IR system was presented. The pan–tilt IR system hardware and MRT monitoring software were developed. An experiment was performed to verify the applicability of the proposed pan–tilt IR scanning method. By comparing the surface temperatures measured using a contact thermometer and the proposed IR system, the contact thermometer could cause inaccurate measurement of surfaces with a non-uniform distribution of temperature. The difference between surface temperatures increased by up to 15 °C and, accordingly, the MRT distributions differed by up to 6 °C within the same space. The proposed IR scanning method showed good applicability in various aspects. This paper reports that the MRT has a significant effect on the occupants’ thermal comfort and also suggests considering MRTs in the real-time evaluation of thermal environment to control various heating and cooling systems appropriately.

Conserving Energy by Expanding the Thermal Comfort Envelope

1978 ◽  
Vol 22 (1) ◽  
pp. 533-536 ◽  
Author(s):  
Frederick H. Rohles
Keyword(s):  
Thermal Comfort ◽  
Indoor Air ◽  
Air Conditioning ◽  
Thermal Environment ◽  
Thermal Conditions ◽  
Heating And Cooling ◽  
American Society ◽  
Psychrometric Chart ◽  
Sedentary Activities

Standard 55–74 entitled “Thermal Conditions for Human Occupancy” which is published by The American Society of Heating, Refrigerating, and Air Conditioning Engineers, (ASHRAE) defines an “acceptable thermal environment” as one in which “at least 80 percent of the normally clothed men and women while engaged in indoor sedentary or near sedentary activities would express thermal comfort.” This is pictured on the ASHRAE psychrometric chart as an envelope that includes dry bulb temperatures between 74°F and 77°F at relative humidities between 20% and 60%. The paper will describe five human factors approaches that have been used or are being considered to expand this envelope and thereby conserve energy. These are (1) the use of small radiant heaters which are installed in the modesty panels of desks so comfort may be attained at lower temperatures; (2) the demonstration that night set-back of thermostats to temperatures as low as 50°F do not effect sleeping patterns; (3) the role that interior decor can play in making people feel warmer; (4) the effect that temperature “swings” associated with solar heating and cooling has upon acceptance of the thermal environment and (5) the acceptance of a reduced quality of indoor air as a result of heating with an increased ratio of recirculated air to outside air.

scholarly journals Behavioural Adaptation for the Thermal Comfort and Energy Saving in Japanese Offices

2019 ◽  
Vol 15 (2) ◽  
pp. 14-25
Author(s):  
Hom B. Rijal ◽  
Michael A. Humphreys ◽  
J. Fergus Nicol
Keyword(s):  
Thermal Comfort ◽  
Energy Use ◽  
Thermal Environment ◽  
Office Buildings ◽  
Behavioural Adaptation ◽  
Indoor Thermal Environment ◽  
Heating And Cooling ◽  
Adaptive Thermal Comfort ◽  
Window Opening ◽  
Behavioural Adaptations

Office workers use a variety of adaptive opportunities to regulate their indoor thermal environment. The behavioural adaptations such as window opening, clothing adjustments, and use of heating/cooling are important factors for adaptive thermal comfort. It is well-known that they are the most important contributors in the adaptive thermal comfort model. Thus, if we understand the behavioural adaptation properly, we can explain the mechanism of the adaptive model. The indoor thermal environment is often adjusted using the air conditioning in Japanese office buildings to improve thermal comfort and productivity. Thus, it is necessary to conduct research on the behavioural adaptation in the offices because the occupant behavior is different from behaviour in dwellings. In order to record the seasonal differences in behavioural adaptation and to develop an adaptive algorithm for Japanese offices, we measured temperatures in 11 office buildings and conducted the thermal comfort and occupant behaviour survey for over a year. We collected 4,660 samples from about 1,350 people. The proportion of ‘open window’ in the free running mode (neither heating nor cooling being used) is significantly higher than that of the air conditioned mode. The behavioural adaptation is related to the outdoor air temperature. The behavioural adaptations such as window-opening, heating and cooling use predicted by regression analysis are in good agreement with the measured data. These findings can be applied to building thermal simulation to predict the behavioural adaptation and energy use in office buildings.

scholarly journals Evaluation of Four Models for Predicting Thermal Sensation in Chinese Residential Kitchen

2019 ◽  
Vol 111 ◽  
pp. 02004 ◽  
Author(s):  
Xiaojie Zhou ◽  
Sumei Liu ◽  
Xuan Liu ◽  
Xiaorui Lin ◽  
Ke Qing ◽  
...  
Keyword(s):  
Thermal Comfort ◽  
Thermal Environment ◽  
Thermal Sensation ◽  
Environmental Parameters ◽  
Outdoor Thermal Comfort ◽  
The Mean ◽  
The University ◽  
Thermal Comfort Model ◽  
Skin Temperatures ◽  
Strong Radiation

Thermal environment in residential kitchen in China is transient and non-uniform and with strong radiation asymmetry from gas stove. Due to the complexity of kitchen thermal environment, it is not sure if previous thermal comfort models can accurately predict the thermal comfort in residential kitchens. In order to evaluate if existing thermal comfort models can be applied for Chinese kitchens, this investigation conducted human subject tests for 20 cooks when preparing dishes in a kitchen. The study measured skin temperatures of the cooks and environmental parameters and used questionnaires to obtain their thermal sensation votes at the same time. The actual thermal sensation votes were compared with the predicted ones by four thermal comfort models: predicted mean vote (PMV) model, dynamic thermal sensation (DTS) model, the University of California at Berkeley (UCB) model, and the transient outdoor thermal comfort model from Lai et al. The results showed that all the models could predict the trend of the thermal sensations but with errors. The PMV model overpredicted the thermal sensations. The UCB and Lai’s models showed a slower change in thermal sensation votes (TSV) after turning on the stove. The DTS model was more accurate than the others in predicting the mean thermal sensation, but with a large variation in predicting individual thermal sensation votes. A better thermal comfort model should be developed for Chinese residential kitchens.

Preference for the Thermal Environment by the Elderly

1969 ◽  
Vol 11 (1) ◽  
pp. 37-41 ◽  
Author(s):  
Frederick H. Rohles
Keyword(s):  
Thermal Comfort ◽  
Thermal Environment ◽  
The Elderly ◽  
Elderly Subjects ◽  
Middle Aged ◽  
College Age ◽  
The Mean ◽  
Modal Values ◽  
Middle Aged Adults

On the basis of the responses of 64 elderly subjects (mean age 75 years) to two questionnaires, temperatures from 32° F to 110° F were classified as cooler-than-comfortable, comfortable, and warmer-than-comfortable. The distribution of comfortable temperatures agree with experimentally derived findings on college-age and middle-aged adults with the mean, median, and modal values falling within the ASHRAE Thermal Comfort Standard 55-66. The results conflict with the criterion stated in the ASHRAE Handbook (1967) that persons over the age of 40 prefer a temperature for comfort of 1° ET higher than that desired by persons below this age.

Radiant Flux Preference of Neonatal Broiler Chicks During Brooding

2018 ◽  
Vol 61 (4) ◽  
pp. 1417-1423
Author(s):  
John E. Linhoss ◽  
Joseph L. Purswell ◽  
Jeremiah D. Davis
Keyword(s):  
Thermal Environment ◽  
Linear Regression Analysis ◽  
Radiant Heat ◽  
Radiant Flux ◽  
Broiler Chicks ◽  
Treatment Area ◽  
The Mean ◽  
Gender Groups ◽  
Mixed Gender ◽  
Broiler House

Abstract. Radiant heat is the most common method of providing supplemental heat in a broiler house. However, little information exists about chick preference for radiant flux. Identifying the ranges of radiant flux that chicks prefer would allow improved management of the thermal environment. The objectives of this study were to determine the radiant flux ranges preferred by broiler chicks during the first eight days of brooding. Three trials were conducted using straight-run broiler chicks. A total of 88 chicks were randomly allocated into two mixed-gender groups and placed into identical 1 m × 4 m pens for 8 d. Heat lamps were used to create radiant flux zones of 30, 70, 175, and 450 W m-2 in each pen. Chicks were allowed to move freely between the zones, and feed and water were available in each treatment area. Chick location was recorded with a camera at 5 min intervals. For each image, non-linear regression analysis was applied to the cumulative proportion of chicks in each treatment. The resulting equations were used to calculate the range of radiant flux values for which 80% of the chicks exhibited a preference. Chicks exhibited a preference for decreasing radiant flux with age. The mean maximum preferred radiant flux for all trials decreased from 409.4 W m-2 at 1 d to 304.4 W m-2 at 8 d. The mean minimum preferred radiant flux for all trials decreased from 114.5 W m-2 at 1 d to 31.4 W m-2 at 8 d. Keywords: Broiler chicks, Brooding, Radiant flux, Radiant heaters, Thermal preference.

scholarly journals Roof-Integrated Green Technologies, Energy Saving and Outdoor Thermal Comfort: Insights from a Case Study in Urban Environment

2021 ◽  
Vol 16 (1) ◽  
pp. 13-23
Author(s):  
Guglielmina Mutani ◽  
Valeria Todeschi
Keyword(s):  
Thermal Comfort ◽  
Energy Saving ◽  
Green Roofs ◽  
Outdoor Thermal Comfort ◽  
Mean Radiant Temperature ◽  
Green Technologies ◽  
Heating And Cooling ◽  
Before And After ◽  
The Mean ◽  
Radiant Temperature

Green urban infrastructures have a significant impact on urban climate mitigation, on indoor and outdoor thermal comfort and on energy performance of buildings. In this paper, outdoor thermal comfort conditions and energy saving for space heating and cooling were investigated before and after the use of roof-integrated green technologies. Existing urban energy and climate models and tools were applied to an urban area located in a Turin (Italy). CitySim, ENVI-met and SOLWEIG tools and a GIS-based model were used to evaluate the mean radiant temperature and the thermal comfort of outdoor spaces before and after the use of vegetated roofs and green surfaces such as the predicted mean vote (PMV), the physiological equivalent temperature (PET) and the universal thermal climate index (UTCI). A GIS-based engineering model and CitySim tool were used to evaluate the energy saving and energy independence index for space heating and cooling after the use of green roofs and solar technologies. According to the shape and the suitability of rooftop elaborated with GIS tools, some roofs were identified as potential green roofs other as potential solar roofs for installing solar thermal collectors and photovoltaic panels. According to the results it is possible to confirm that the use of green roofs and urban greenery can decrease the mean radiant temperature until about 10℃ during summer season, improving outdoor thermal comfort conditions and energy savings with a reduction of 12% for space cooling energy consumption.

scholarly journals Comparative Analysis of Energy Use and Human Comfort by an Intelligent Control Model at the Change of Season

Energies ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 6023
Author(s):  
Sung Hoon Yoon ◽  
Jonghoon Ahn
Keyword(s):  
Thermal Comfort ◽  
Intelligent Control ◽  
Energy Use ◽  
Thermal Environment ◽  
Operating Time ◽  
Adaptive Controller ◽  
Indoor Thermal Comfort ◽  
Heating And Cooling ◽  
Proposed Model ◽  
Deterministic Control

For improving control methods in the thermal environment, various algorithms have been studied to satisfy the specific conditions required by the characteristics of building spaces and to reduce the energy consumed in operation. In this research, a network-based learning control equipped with an adaptive controller is proposed to investigate the control performance for supply air conditions with maintaining the levels of indoor thermal comfort. In order to examine its performance, the proposed model is compared to two different models in terms of the patterns of heating and cooling energy use and the characteristics of operational signals and overshoots. As a result, the energy efficiency of the proposed control has been slightly decreased due to the energy consumption increased by precise controls, but the thermal comfort has improved by about 10.7% more than a conventional thermostat and by about 19.8% more than a deterministic control, respectively. This result can contribute to the reduction of actual installation and maintenance costs by reducing the operating time of dampers and the energy use of heating coils without compromising indoor thermal comfort.

scholarly journals Environment in poultry production covered with thermal and aluminum roofing tiles

2015 ◽  
Vol 35 (2) ◽  
pp. 206-214
Author(s):  
FERNANDO G. DE OLIVEIRA ◽  
WANESSA M. GODOI ◽  
ROBERTA PASSINI
Keyword(s):  
Thermal Comfort ◽  
Thermal Environment ◽  
Radiant Heat ◽  
Poultry Production ◽  
Thermal Indices ◽  
Significance Level ◽  
Temperature And Humidity ◽  
Humidity Index ◽  
The Difference ◽  
Globe Temperature

Brazil is a country of tropical climate, a fact that hinders the poultry production in the aspect of thermal comfort. Thus, we aimed to evaluate the thermal environment in commercial poultry houses with different covers during the months of December 2012 to May 2013, in the municipality of Rio Verde, Goiás. The experimental design was completely randomized in split plots with factorial arrangement of treatments 2x3, being two shed models (thermal and aluminum roof tiles) and three sections within each shed (initial, central and final) for 182 days, having the days as replicates. The thermal environment was assessed through thermal comfort indices: Temperature and Humidity Index, Black Globe Temperature and Humidity Index, Radiant Heat Load and Enthalpy. The data was analyzed by SISVAR 5.1., through the analysis of variance, the Scott Knott test used to compare the means, considering a significance level of 1%. The results showed a significant statistical difference between the sheds and the points assessed (P < 0.05). The thermal shed had the lowest values for the environmental variables (Dbt and Bgt) and thermal indices studied, but larger values for the RH compared to the shed with aluminum covering. The use of thermal covers minimizes the difference in temperature range throughout various times of the day, being at 14:00 o'clock the prominence time to others.

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