6.4.2011

Tampere University of TechnologyFibre Material Science

KMT-1606:2011Clothing PhysiologyDemonstrations 6th and 20th April, 2011

Minna Varheenmaa, Researcher, M.Sc.(Tech.)(Ref. Docent, Dr.Techn. Harriet Meinander. Clothing physiology.

Course material)minna.varheenmaa@tut.fi

Minna Varheenmaa_Clothing Physiology2011

6.4.2011

Demonstration: Cylinder

• Demonstrations (Kawabata and Cylinder) + report (4 persons/report)• Wednesday 6th April, 2011 Cylinder measurements, 9-11 a.m.

K4441 (and a brief visit to the climatic chamber)• Wednesday 20th April, 2011 Kawabata measurements, 9-11 a.m.

K4441 (and a brief visit to the lab)

Minna Varheenmaa_Clothing Physiology2011

6.4.2011

Contents

1. Introduction2. Purpose3. Cylinder - Construction4. Principle of the measurement5. Measured values and test results6. Task: Measured values of sample ABC7. A short visit to a climatic chamber

Minna Varheenmaa_Clothing Physiology 2011

6.4.2011

Demonstration 1:Thermal comfort properties – cylinder

Minna Varheenmaa_Clothing Physiology 2011

Thermal sweating manikin - Coppelius New thermal sweating cylinder

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Demonstration Thermal Sweating Cylinder

Purpose: -to simulate simultaneously the continuous heat and sweat/moisture production of

human body in certain action level and environmental conditions-to simulate heat production cylinder surface is heated to a T of 34 °C that corresponds

human skin T-to simulate sweating water is supplied through the 24 sweating glands that are evenly

distributed on the surface to evaporate to the environment-to simulate the activity level the sweating level can be adjusted from 0-300 g/m2*h-measurement is made in a climatic chamber that simulates the selected environmental

conditions: the ambient temperature and relative humidity (air flow in the chamber is set to 0.3…0.5 m/s)

-heat is lost from the cylinder in the form of convection and radiation (dry heat loss) and also through evaporation of supplied water (evaporative heat loss)

-clothing/material layers form a barrier (thermal resistance Rct) between the heated cylinder surface and the colder environment and thus reduce the heat loss

-water vapour is transferred through the textile layers only partly in vapour form while partly it condensates within them

-Rct of textile materials is calculated from the heat input and the temperature values-WV (water vapour) transmission is calculated from the water input and absorption

values

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Cylinder - construction

-3D-shape (cylinder) for simulating human body shape-the wall is stiff foam plastic (old one thicker) and new one has plastic

composite trunk-for water supply thin water tubes are fixed into 24 drilled holes on the surface-for heating there is a an electric heating wire + protective insulating film

covering the outer surface of the wall-for spreading the heat evenly from the wire there is a metal layer+ plastic layer

for mechanical protection-the outmost layer, the skin surface is a laminate with nonwoven back for

distributing the water from the tubes to a larger area and with expanded microporous PTFE-membrane face to transmit water vapour but not the liquid water and a net

-consists of three sections or rings: test area and for preventing heat leakage from test area there are upper and lower rings with separate heating systems

-water flows with its own weight from the water reservoir

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Cylinder - construction

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Principle of the measurement

-starting the heating of the system after setting of test parameters to the computer controlled system: Ta (°C), RH (%), Ts (°C), sweating level (g/m2*h), test time (min)

-dressing the cylinder with the selected textile material layer combination and placing the temperature sensors inbetween the layers

-after reaching the equilibrium between the set up ambient T and RH and surface T values the measurement is switched on:1. dry heat measurement (120 min)2. sweating measurement with water supply (180 min)

-measurement data collection by the software normally 1 min intervals and calculating 10 min average

-water reservoir on a balance weighing the water supply during the test-cylinder on a balance weighing the condensed water to the whole

system (measurement with nude cylinder to exclude the cylinder part)

-weighing of test samples before and immediately after the test

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Principle of the measurement

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Measured values and test results

Measured values are:-heat supply (W/m²), surface temperature (°C), temperatures at

different layers (Pt sensors, °C), total weight increase during the test (g) and weight increase of the separate clothing layers (g).

The test results based on the measured values are: -thermal resistance or insulation in dry test Rcyl (m²·K/W), evaporative

heat loss He (W/m²), water vapour permeability me (%) and corrected thermal resistance in sweating test Rcyl, corr (m²·K/W).

(Ref. Meinander, H. Physical measurements of clothing thermoregulatory properties. AUTEX conference, 2007.)