Conduct an experiment

Demo

THERMAL MANNEQUIN LABORATORY

The Thermal Mannequin Laboratory provides an innovative new technology for measuring the heat exchange properties of protective clothing worn by persons engaged in hot outdoor activities.

Convective and radiative heat exchange properties of garments can be documented while being exposed to wind and Infrared radiation. Tests performed in this laboratory to-date have contributed to the design and development of new clothing systems for agricultural workers. The principles used in the new garment designs can now also be incorporated into garments worn by athletes and other persons exposed to hot outdoor environments.

Allowing students around the world to participate in such experiments, greater individual learning and improved teaching efficiencies in the field of ergonomics is envisioned.

Boise State University has allowed the laboratory to be opened to anyone through this demonstration page.

This project is based on collaboration with the following partner institutions:

Department of Industrial Engineering and Logistics Management, Hong Kong University of Science and Technology, Hong Kong

Faculty of Textile Technology, University of Zagreb, Zagreb, Croatia

Project Sponsors:

Department of Community and Environmental Health, College of Health Sciences, Boise State University

Technology Transfer Office, Division of Patents and Licensing, University of South Florida - Tampa

The Experiment

Quick Start Instructions

Turn on the Thermal Mannequin - this inflates quite fast, but for taking readings and conducting the experiment to obtain accurate results, a 10 minute period should elapse before first data readings are taken.
With the camera direction buttons, you may look around the room and zoom in on any area of interest.
Options to turn on a) the fan to cool the temperature of the mannequin or b) the Infra-Red heat lamps to warm up the mannequin. Again, 10 minutes is required before accurate data readings can be taken as the mannequin must reach a state of equilibrium.
At the end of the session when you exit the live controls, all equipment will be automatically turned off for safety reasons.

How the manikin works

The inflatable thermal manikin technology is based on an open circuit system which maintains a constant air pressure and a constant volume flow rate inside the manikin. In addition, air entering the manikin is heated and maintained at a constant temperature.

The heated input air is distributed symmetrically throughout the manikin. Air return tubes inside the arms and legs channel air flow from the torso to the extremities before allowing the air to exit the system.

As the heated air flows through the manikin, it cools. Normally, the temperature of the air exiting the manikin will be lower than the temperature entering the manikin. The difference between the two temperatures will depend on the environmental conditions and the clothing worn by the manikin.

How to determine heat exchange

The manikin has been calibrated based on the difference between input air temperature and exit air temperature (∆ t).

A temperature difference (∆ t) of 0.030C corresponds to a total manikin heat exchange of 1.0 watt.

Under standard laboratory temperature conditions, the difference between the input air temperature and exit air temperature for the semi-nude manikin (∆t) is 6.90C. This difference corresponds to 230 watts of total manikin heat loss.

How to calculate the insulation value of clothing, the effects of wind cooling, and heat gain from IR radiation

All measurements are made relative to the heat loss measured for a semi-nude configuration (male manikin with shorts, female manikin with bikini).

When the manikin wears clothing, the temperature difference between input air and exit air (∆ t) will be lower than that for the standard semi-nude configuration. This is due to insulation.

Example #1 (Wearing a jacket)

Jacket: (∆ t) = 5.0⁰C

Heat loss: 5.0⁰C = 166 watts

0.03

Jacket insulation: 230 watts - 166 watts = +64 watts

If the manikin is exposed to wind, the temperature difference between input air and exit air (∆ t) will be greater than that for the standard semi-nude configuration. This is due to convective cooling.

Example #2 (Exposure to wind)

Wind: (∆ t) = 8.5⁰C

Heat loss: 8.5⁰C = 283 watts

0.03

Wind cooling: 230 watts - 283 watts = - 53 watts

If the manikin is exposed to Infrared heat radiation, the temperature difference between input air and exit air (∆ t) will be lower than that for the standard semi-nude configuration. This is due to radiative heating.