SBIR-STTR Award

The accuracy of Clo values measured with a thermal manikin is strongly dependent on the degree to which the skin temperature is known. Spatial and set-point temperature variations combine to increase the error in the measurement. Additionally, evaporative cooling accounts for a significant thermal loss in most clothing systems. Measurement Technology Northwest (MTNW) proposes an innovative adaption of heat pipe technology to a 17 zone copper thermal manikin. This design will provide isothermal conditions at the condenser skin surfaces. Integrated in this design is a novel irrigated skin which will accurately reproduce physiological evaporation rates and avoid thermal decoupling associated with soft artificial skin systems.

Benefits:
The successful completion of Phase I will lead to the design and Phase II fabrication of the Heat Pipe Thermal Manikin. The manikin will be delivered to the sponsor to provide very accurate Clo measurements, including the latent heat loss components of garments.

Keywords:
Thermal Manikin Thermal Manikin Heat Pipe Heat Pipe Sweating Skin Sweating Skin Isothermal Isothermal latent Heat Loss latent Heat Loss Clo Clo

The accurate assessment of clothing systems using thermal manikins is dependent on tolerance of heat flux and temperature measurements, and the ability to measure the permeability of the garment. Close tolerance measurement of electrical temperature and power transducers is a common practice. However, spatial temperature variations on the skin of the manikin and the lack of well controlled irrigated skin systems are significant limits in manikins currently in use. Measurement Technology northwest proposes to fabricate and deliver the innovative thermal manikin whose feasibility was demonstrated in Phase I of this program. This heat pipe driven manikin design will limit spatial surface temperature variations to less than +/-0.1 degrees C at standard operating heat fluxes. Additionally, the controlled delivery irrigated skin will provide a well dispersed steady state perspiration rate in the physiological ranges of 100 to 500 ml/m(2)/hour.

Benefits:
The Phase II deliverable will be a heat pipe thermal manikin with an irrigated skin. This manikin will provide Army researchers with a more accurate and comprehensive emans to evaluate clothing systems than previously available.

Keywords:
Thermal Manikin Thermal Manikin Heat Pipe Heat Pipe Sweating Skin Sweating Skin Isothermal Isothermal latent Heat Loss latent Heat Loss Clo Clo