Revisiting the use of globe thermometers to estimate radiant temperature in studies of heating and ventilation

Guo, Hu; Teitelbaum, Eric; Houchois, Nicholas; Bozlar, Michael; Meggers, Forrest

doi:10.1016/j.enbuild.2018.08.029

Cited by 38 publications

(22 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, Guo et al [29] and Meggers et al [30] suggest that the traditional methods of measuring and calculating ! may not be accurate, even at low air velocities.…”

Section: Introductionmentioning

confidence: 99%

Comparison of mean radiant and air temperatures in mechanically-conditioned commercial buildings from over 200,000 field and laboratory measurements

Dawe

Raftery

Woolley

et al. 2020

Energy and Buildings

View full text Add to dashboard Cite

We assessed the difference between mean radiant temperature (! ) and air temperature (! ) in conditioned office buildings to provide guidance on whether practitioners should separately measure ! or operative temperature to control heating and cooling systems. We used measurements from 48 office buildings in the ASHRAE Global Thermal Comfort Database, five field studies in radiant and all-air buildings, and five test conditions from a laboratory experiment that compared radiant and all-air cooling. The ASHRAE Global Thermal Comfort Database is the largest of these three datasets and most representative of typical thermal conditions in an office; in this dataset the median absolute difference between ! and ! was 0.4 (with 5 th , 25 th , 75 th , and 95 th percentiles = 0.2, 0.2, 0.6, and 1.6 °C). More specifically, the median difference shows that was 0.4 warmer than (with 5 th , 25 th , 75 th , and 95 th percentiles = -0.4 °C, 0.2 °C, 0.6 °C, and 1.6 °C). The laboratory experiments revealed that in a radiant cooled space ! was significantly (p<0.05) cooler than ! (average difference -0.1 ! ), while in the all-air cooled space ! was significantly (p<0.05) warmer than ! (average difference +0.3 ! ). These observations indicate that ! and ! are typically closer in radiant cooled spaces than in all-air cooled spaces. Although the differences are significant, the effect sizes are negligible to small based on Cohen's d and Spearman's rho. Therefore, we conclude that measurement of ! is sufficient to estimate ! under typical office conditions, and that separate measurement of ! or operative temperature is not likely to have practical benefits to thermal comfort in most cases -this is especially true for buildings with radiant systems. Furthermore, spatial and temporal variations in ! can be greater than or equal to the difference between ! and ! at any one location in a thermal zone, thus we expect that such variations typically have a greater impact on occupant thermal comfort than the differences between ! and ! .

show abstract

“…Furthermore, Guo et al [29] and Meggers et al [30] suggest that the traditional methods of measuring and calculating ! may not be accurate, even at low air velocities.…”

Section: Introductionmentioning

confidence: 99%

Comparison of mean radiant and air temperatures in mechanically-conditioned commercial buildings from over 200,000 field and laboratory measurements

Dawe

Raftery

Woolley

et al. 2020

Energy and Buildings

View full text Add to dashboard Cite

show abstract

“…Its instantaneous measured values differed from mean air temperature and mean floor temperature from −0.85 °C to 0.92 °C and from −3.90 °C to 2.48 °C, respectively. Regarding comments presented in [64,[90][91][92] operative temperature was calculated as average of air and radiant components [93,94].…”

Section: Thermal Comfort According To En Iso 7730mentioning

confidence: 99%

Selected Aspects of Indoor Climate in a Passive Office Building with a Thermally Activated Building System: A Case Study from Poland

Michalak

2021

Energies

View full text Add to dashboard Cite

Modern buildings with new heating, ventilation and air conditioning (HVAC) systems offer possibility to fit parameters of the indoor environment to the occupants’ requirements. The present paper describes the results of measurements performed in an office room in the first Polish passive commercial office building during four months of normal operation. They were used to calculate parameters describing thermal comfort: vertical air temperature profile, floor surface temperature, predicted mean vote (PMV) and predicted percent of dissatisfied (PPD). Obtained results confirmed good thermal conditions in the analysed room. The average temperature of the floor’s surface varied from 20.6 °C to 26.2 °C. The average vertical air temperature, calculated for working days, was from 22.5 °C to 23.1 °C. The temperature difference between the floor and 5 cm below the ceiling was from −0.9 °C to 6.3 °C. The PMV index varied from 0.52 to 1.50 indicating ‘slightly warm’ sensation, in spite of ‘neutral’ reported by employees. Also measured cooling and heating energy consumption was presented. The performed measurements confirmed the ability of thermally activated building system (TABS) to keep good thermal conditions.

show abstract

“…An analysis [51] of field measurements in ASHRAE Global T a T o Thermal Comfort Database II [52] and additional laboratory testing reported similar differences in air and radiant temperatures, and they suggested as an appropriate estimate of mean T a radiant temperature when it is not readily available. Moreover, recent studies have reported systematic errors when using traditional globe thermometers to measure radiant temperature [53,54]. For these reasons, it seems is sufficient as an input parameter for calculating T a long-term indices when has not been measured.…”

Section: Use Of Air or Operative Temperaturementioning

confidence: 99%

Improved long-term thermal comfort indices for continuous monitoring

Parkinson

Schiavon

et al. 2020

Energy and Buildings

View full text Add to dashboard Cite

Thermal comfort standards have suggested a number of physical indices which can be calculated from either building simulations or in situ physical monitoring to assess the long-term thermal comfort of a space. However, the prohibitively high cost of sensor technologies has limited the applications of these physical indices, and their usefulness has never been established using data collected in real buildings. This paper is the first assessment of the six types of existing indices (23 total) found in standards and five types of new indices (36 total) and their correlation with the long-term thermal satisfaction of building occupants. Correlation analyses were based on continuous thermal comfort measurements and post-occupancy evaluation surveys from four air-conditioned office buildings in Sydney, Australia. We found that the majority of existing indices, especially those based on predicted mean vote (PMV) and predicted percentage dissatisfied (PPD) metrics, have a weak correlation with thermal satisfaction. The percentage of time outside a temperature range was the best-performing index from the standards (). A new index based on the percentage of − .63 r = 0 time that daily temperature range is greater than a threshold reported the strongest correlation () with thermal satisfaction for this dataset. The results suggest that − .8 r = 0 occupants' long-term thermal comfort is influenced more by pronounced excursions beyond some acceptable temperature range and large variations in daily temperature than the average experience over time. These findings support the use of continuous monitoring technologies for long-term thermal comfort evaluation and inform potential amendments of international thermal comfort standards.

show abstract

Revisiting the use of globe thermometers to estimate radiant temperature in studies of heating and ventilation

Cited by 38 publications

References 27 publications

Comparison of mean radiant and air temperatures in mechanically-conditioned commercial buildings from over 200,000 field and laboratory measurements

Comparison of mean radiant and air temperatures in mechanically-conditioned commercial buildings from over 200,000 field and laboratory measurements

Selected Aspects of Indoor Climate in a Passive Office Building with a Thermally Activated Building System: A Case Study from Poland

Improved long-term thermal comfort indices for continuous monitoring

Contact Info

Product

Resources

About