Improving Mean Radiant Temperatures Sensing Using Multidirectional Non-Contacting Temperature Sensors to Avoid Convective Errors With Globe Thermometers

Forrest Meggers, Alexander Kim, Sean Rucewicz, Coleman Merchant, Kianwee Chen, Eric Teitelbaum

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

We evaluate a simple "cube"device for measuring Mean Radiant Temperature (MRT) as an alternative to the globe thermometer. The device uses 6 orthogonal non-contacting surface temperature sensors on the faces of a cube to evaluate the MRT at a point. Each sensor consists of a thermopile and IR filter and internal circuitry to output a temperature based on blackbody emission from surfaces, and are not sensitive to air movement, which a globe thermometer must be calibrated for. The 6 orthogonal measurements are averaged to estimate the Mean Radiant Temperature, and opposing sensors on the cube structure are used to produce radiant asymmetry data. We compare this data to a standard black globe under conditions where free and forced convection cause the globes to be very inaccurate as we have shown in previous work. This paper demonstrates the 6-sided cube can eliminate the error of globes due to sensitivity to changing air movement and convection. We experimentally demonstrate that the globes are limited by self-induced buoyancy flow, with the current ASHRAE standard method resulting in 50% lower separation of MRT from the air temperature (24 deg C air temp, 29 deg C globe MRT, and 35 deg C cube temp). A proposed mixed convection model for globe correction also produces a result that agrees better with the cube results. Finally we propose future work to better consider how overlapping fields of view of the 6 sensors affect results as evaluated by rotating the device 45 degrees.

Original languageEnglish (US)
Title of host publication2022 IEEE International Workshop on Metrology for Living Environment, MetroLivEn 2022 - Proceedings
PublisherInstitute of Electrical and Electronics Engineers Inc.
Pages18-22
Number of pages5
ISBN (Electronic)9781665408936
DOIs
StatePublished - 2022
Event2022 IEEE International Workshop on Metrology for Living Environment, MetroLivEn 2022 - Cosenza, Italy
Duration: May 25 2022May 27 2022

Publication series

Name2022 IEEE International Workshop on Metrology for Living Environment, MetroLivEn 2022 - Proceedings

Conference

Conference2022 IEEE International Workshop on Metrology for Living Environment, MetroLivEn 2022
Country/TerritoryItaly
CityCosenza
Period5/25/225/27/22

All Science Journal Classification (ASJC) codes

  • Building and Construction
  • Instrumentation
  • Human Factors and Ergonomics

Keywords

  • mean radiant temperature
  • radiant heat transfer
  • radiant sensor
  • surface temperature
  • thermal comfort

Fingerprint

Dive into the research topics of 'Improving Mean Radiant Temperatures Sensing Using Multidirectional Non-Contacting Temperature Sensors to Avoid Convective Errors With Globe Thermometers'. Together they form a unique fingerprint.

Cite this