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Musa, A. I.
Department of Mechanical Engineering, Moshood Abiola Polytechnic, Abeokuta, Nigeria
Ismaila, S. O.
Department of Mechanical Engineering, Federal University of Agriculture, Abeokuta, Nigeria
Waheed, M. A.
Department of Mechanical Engineering, Federal University of Agriculture, Abeokuta, Nigeria
Olayanju, T. M.
Department of Agricultural Engineering, Federal University of Agriculture, Abeokuta, Nigeria
ABSTRACT
This study analysed the metabolic exergy of
human body during block laying in an outdoor environment. Two hundred and four
masons were investigated across the three senatorial districts of Ogun State,
Nigeria with distributions of 50.98, 30.88 and 18.14% for Central, West and
East respectively using snowball sampling technique. This technique was used
due to the inaccessible and hard to find masons that laid blocks outdoor. The
meteorological (air temperature, and radiant temperature, relative humidity,
wind speed and solar radiation), physiological (skin temperature, and core
temperature) were measured and recorded hourly for 10 hours per day at an
average of 17 masons every month from May 2013 to April 2014. Models were
developed to determine the metabolic exergy, exergy in [(1-Ta/Tc) ӼM], exergy out [(1-Ta/Tsk) ӼM], exergy destroyed [(1-Ta/Tc)
ӼM - (1-Ta/Tsk) ӼM], The data collected were
subjected to descriptive statistics using SPSS 21.0. The mean values of air
temperature, radiant temperature, relative humidity, wind speed and solar
radiation were 33.13 ± 2.34 oC, 34.00 ± 2.13 oC, 55.32 ± 6.40%, 0.48 ± 0.03 m/s
and 662.73 ± 100.31 W/m2 respectively. The skin temperature and core
temperature were 34.02 ± 0.54, 36.39 ± 0.14 oC, respectively. The metabolic
exergy ӼM, exergy in, out and
destroyed by the mason were 120.62 ± 10.38, 10.25 ± 6.19, 2.38 ± 6.40 and 7.88
± 1.99 W respectively. The study concluded that the rate and proportions of the
different components in the exergy balance equation (exergy input, destroyed,
and output) vary according to the outdoor temperature and humidity. The
metabolic exergy of the mason was determined as 120.60 (±10.38) W which
conformed to the ISO standard.
Keywords: Exergy, Metabolic, temperature, Human body, Blocklaying, Outdoor, Mason
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Published
Wednesday, June 21, 2017
Issue
Vol. 3 No. 1, JUNE 2017
Article Section
GENERAL
The contents of the articles are the sole opinion of the author(s) and not of UJET.
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