calcHbExUnsteady: Human Body Exergy Consumption Rate using Unsteady State...

View source: R/calcHbExUnsteady.R

calcHbExUnsteadyR Documentation

Human Body Exergy Consumption Rate using Unsteady State Method

Description

calcHbExUnsteady Function calculates the human body exergy consumPtion rate using unsteady state method based on a series of environmental variables.

Usage

calcHbExUnsteady(ta, tr, rh, vel, clo, met, tao, rho, frad = 0.7, 
eps = 0.95, ic = 1.085, ht = 171, wt = 70, tcr = 37, tsk = 36, basMet = 58.2,
warmUp = 60, cdil = 100, sigmatr = 0.25, dateTime)

Arguments

ta

a numeric value presenting air temperature in [degree C]

tr

a numeric value presenting mean radiant temperature in [degree C]

rh

a numeric value presenting relative humidity [%]

vel

a numeric value presenting air velocity in [m/s]

clo

a numeric value presenting clothing insulation level in [clo]

met

a numeric value presenting metabolic rate in [met]

tao

a numeric vector presenting outdoor air temperature in [degree C]

rho

numeric vector presenting outdoor relative humidity [%]

frad

a numeric vector presenting the fraction of body exposed to radiation 0.7(for seating), 0.73(for standing) [-]

eps

a numeric vector presenting emissivity [-]

ic

a numeric vector presenting permeability of clothing: 1.084 (average permeability), 0.4 (low permeability)

ht

a numeric vector presenting body height in [cm]

wt

a numeric vector presenting body weight in [kg]

tcr

a numeric vector presenting initial value for core temperature in [degree C]

tsk

a numeric vector presenting initial value for skin temperature in [degree C]

basMet

a numeric vector presenting basal metabolic rate in [met]

warmUp

a numeric vector presenting length of warm up period, i.e. number of times, loop is running for HBx calculation.

cdil

a numeric vector presenting value for cdil in 2-node model of Gagge

sigmatr

a numeric vector presenting value for cdil in 2-node model of Gagge.

dateTime

a POsIxct vector of the times of measurement.

Details

This function requires vectors of data including the corresponding time stamp. In case the time between two measurements is more than a minute, intermediate values are interpolated.

Value

Returns a data.frame with the following columns. Exergy input

xInmetu

Exergy input through metabolism

xInmetwcu

Label warm/ cold for exergy input through metabolism

xInAIRwcu

Exergy input through inhaled humid air

xInAIRwcwcu

Label warm/ cold for exergy input through inhaled humid air

xInAIRwdu

Exergy input through inhaled dry air

xInAIRwdwdu

Label wet/ dry for exergy input through inhaled dry air

xInLUNGwcu

Exergy input through water lung

xInLUNGwcwcu

Label warm/ cold for exergy input through water lung

xInLUNGwdu

Exergy input through water lung

xInLUNGwdwdu

Label wet/ dry for exergy input through water lung

xInsheLLwcu

Exergy input through water from sweat

xInsheLLwcwcu

Label warm/ cold for exergy input through water from sweat

xInsheLLwdu

Exergy input through water from sweat

xInsheLLwdwdu

Label wet/ dry for exergy input through water from sweat

xInraDu

Exergy input through radiation

xInraDwcu

Label warm/ cold for exergy input through radiation

xIntotaLu

total exergy input

Exergy output

xoutstorecoreu

Exergy stored in core

xoutstoreshelu

Exergy stored in shell

xoutaIRwcu

Exergy output through exhaled humid air

xoutaIRwcwcu

Label warm/ cold for exergy output through exhaled humid air

xoutaIRwdu

Exergy output through exhaled dry air

xoutaIRwdwdu

Label wet/ dry for exergy output through exhaled dry air

xoutswEATwcu

Exergy output through water vapour from sweat

xoutswEATwcwcu

Label warm/ cold for exergy output through water vapour from sweat

xoutswEATwdu

Exergy output through water vapour from sweat

xoutswEATwdwdu

Label wet/ dry for exergy output through water vapour from sweat

xoutraDu

Exergy output through radiation

xoutraDwcu

Label warm/ cold for exergy output through radiation

xoutCONVu

Exergy output through convection

xoutCONVwcu

Label warm/ cold for exergy output through convection

xouttotaLu

total exergy output

Exergy balance

xconsu

total exergy consumPtion

Additional values

tsku

Calculated skin temperature

tcru

Calculated core temperature

wu

Calculated skin wettedness

Note

According to Gagge's paper (1973), the value of 'cdil' may vary between 75 and 225 and 'sigma-tr' between 0.25 and 0.75. There is a note in the appendix of his paper saying two things: 1) whatever the values taken for cdil and sigma-tr, there must be no significant change in resulting thermal equilibrium. But, the values taken for cdil and sigmaTr do affect time to equilibrium. According to the analysis of schweiker et al. (2015), the values of 100 and .25 lead to the best fit of calculated and observed skin temperature.

Author(s)

This function is based on a VBA code developed by masanori Shukuya. transformation of VBA-code and Excel procedures into R syntax by Marcel Schweiker.

References

Schweiker, Kolarik, Dovjak & Shukuya (2016) <doi:10.1016/j.enbuild.2016.01.002>

Shukuya (2015) Calculation of human body-core and skin-layer temperatures under unsteady-state conditions-for unsteady-state human-body exergy analysis-, internal report of exergy-research group, Tech. rep.

See Also

see also calcComfInd

Examples

## Define environmental parameters
ta <- seq(20,25,.1)
tr <- ta
rh <- rep(50, length(ta))
vel <- rep(.1, length(ta))
clo <- rep(.8, length(ta))
met <- rep(1.2, length(ta))
tao <- rep(5, length(ta))
rho <- rep(80, length(ta))
dateTime <- as.POSIXct(seq(0,by=60,length.out=length(ta)), origin="1970-01-01")
## Calculation of human body exergy consumPtion rate
calcHbExUnsteady(ta, tr, rh, vel, clo, met, tao, rho, dateTime = dateTime)$xconsu

comf documentation built on May 29, 2024, 8:02 a.m.