In the Lab for Clothing Comfort and Performance, we can characterize the thermal properties of clothing material and ensembles, such as the thermal and the evaporative resistance. These thermal properties are associated with the physical properties of the clothing material such as thickness, thermal diffusivity, porosity, as well as the size of air gap in between of human skin and the fabric. These thermal properties, together with the human activity level (metabolic rate), and the environmental conditions (temperature, wind speed, humidity) can be used to predict the human comfort and heat stress level.
In this facility we carry out the following tasks:
- textile material comfort related property studies
- complex heat and moisture transfer analyses
- study interactions between clothing, the human body, and the environment
The major instrumentation includes: a guarded sweating hot plate (skin model), instruments to measure the moisture vapor transmission rate and air permeability, as well as optical instruments for the video-based analyses of dynamic contact angles, and sweating hand, sweating manikin, etc.
Sweating Hot Plate
The sweating hot plate instrumentation provides an assessment of heat and moisture (vapor) transport through the material. The sweating guarded hot plate determines the thermal resistance (insulation), evaporative resistance (breathability/permeability) of a material, as well as the Total Heat Loss from the plate through the fabric. These are widely used characterizations for determining a clothing system’s impact on heat and moisture transfer between the wearer and the environment. We use a large sweating hot plate to carry out several tests based on a range of different standards.
The sweating manikin systems are used to evaluate entire garment systems (or components of garment systems) regarding heat and moisture management, assessing their insulation and moisture breathability. By measuring these values on a human form, the garments can be evaluated under realistic field conditions while varying environmental parameters in a controlled manner. Effects of fit, garment construction and design (including air gaps) are taken into account. Hence the sweating manikin is capable of providing much better estimates of the heat loss of the entire apparel ensemble under different environmental conditions. In addition, the manikin can also be used to simulate walking through the use of an articulated walking frame.
The sweating hand is designed to evaluate heat and moisture management properties of glove systems. This equipment simulates heat and sweat production and transportation which allows us to evaluate the thermal comfort of gloves for a range of environmental parameters. Simultaneous heat and moisture transport through the glove system, including local variations in different areas of the hand can be quantified. As there are no established standards for sweating hand testing, we use the same environmental parameters as in the sweating manikin test standards.
Video-based Optical Contact Angle Measuring Instrument
Our video-based optical contact angle measuring system allows for state-of-the-art professional fabric/film contact angle measurements as well as drop shape analyses which can also be carried out on relatively large samples. The OCA 15Pro has long x- and y-axes and comes with custom made high temperature furnaces (developed in our lab).
Dynamic Contact Angle Measuring Instrument and Tension
The dynamic contact angle measuring instrument and tensiometer DCAT 11 is the standard instrument for the weight-based measurement of contact angles, surface and interfacial tension, critical micelle formation concentration, density, sedimentation and penetration rate, as well as penetration resistance.