SSC-Natick Press Release
U.S. Army Soldier Systems Center-Natick
Public Affairs Office
Natick, MA 01760-5012
Contact: Chief, Public Affairs Office
Date: August 3, 2004
Thermal test facility coming to installation
NATICK, Mass. -- Construction of a joint-use thermal test facility at the U.S. Army Soldier Systems Center here, is scheduled to begin January 2005. The opening is set for 2006.
The state-of-the-art 12,500 square-foot facility will house a propane fuel cell and laboratories for evaluating the effect of flame or thermal threats, and assist in the development of improved clothing, materials and equipment to protect individual warfighters.
The 2004 Defense Appropriation Act authorized the installation's Natick Soldier Center $5.4 million to build the facility, which will include a conference room and commons, and enable for the first time testing of complete clothing ensembles in a consolidated location.
"We have always had a need for this type of test facility," said Joel Carlson, a research chemist on the Materials Science Team, who along with Calvin Lee, an aerospace engineer on the Airdrop Technology Team, are overseeing the building project. "Flame and thermal threats are increasing, and it's more cost-effective to have everything in one facility."
Thermal and fire testing is now accomplished with equipment at facilities in North Carolina and Massachusetts, and the new facility will combine some testing equipment already on-site.
The Air Force transferred all fire testing responsibilities to the Soldier Systems Center five years ago, and other organizations will be encouraged to use the new facility, according to Lee.
"I have no doubt we can generate (Cooperative Research and Development Agreements) and testing contracts with fabric clothing companies," Carlson added.
Environmental controls are painstakingly detailed to prevent pollution.
"Environmental concerns are a No. 1 priority," Carlson said. "When testing is done, we want to make sure the air and water are as clean as before we do the testing."
Filling the largest test space, researchers will evaluate burn injury protection and thermal characteristics of clothing systems, materials and equipment in the propane fire cell. Propane is the industry standard fuel used in flame testing and safe for the environment, Carlson said.
The Navy Clothing and Textile Research Facility, also located at the Soldier Systems Center, will provide a thermal oven to assess convective heat transfer of clothing and a new articulated walking thermal manikin.
The manikin, developed by Physical Sciences Inc. in Andover, Mass., contains 122 skin heat sensors and simulates a person walking near or through a flame. The walking manikin will join an American Society of Testing and Materials stationary manikin, also equipped with 122 skin heat sensors, to test the effect of flash fires on clothing systems.
A propane fire pit 6 feet by 10 feet can test tents and individual equipment. The pit offers extra flexibility for testing future equipment.
"We wanted to put the pit in there to meet future mission requirements," Carlson said.
The thermal radiation testing cell will provide the technology to irradiate areas of uniform systems 1 square foot or smaller to study the interaction of uniform layers and components, such as flaps, closures and linings, on the systems' ability to protect against flame and thermal energy.
This capability provides a transition between swatch testing and production of prototype garments. An electric arc provides ultraviolet, visible and near-infrared radiation with a spectral distribution similar to that of the sun.
Broad wavelength range, irradiation exposure times of milliseconds to hours, and flexibility to vary the intensity and area of exposure permits thermal radiation testing equipment also to be used to study and develop material coatings and application techniques.
Existing and candidate uniform materials will be evaluated for their ability to protect against flame, laser and thermal radiation in the carbon dioxide laser cell. Energy associated with this type of laser is absorbed by most materials, resulting in rapid heating.
Furthermore, the carbon dioxide laser can be used to study materials processing methodologies.
The ability to concentrate a laser beam into a small area, deliver it precisely to a given spot, and control both the intensity and duration of the beam, provides a method of localizing the heating of a material. A semiconductor, for instance, can be lased to modify its electronic properties without changing the overall mechanical properties.
Centered around the three test cells is the control room. It will allow direct viewing and operation of the walking manikin, stationary manikin, tent test pit, thermal radiation testing and carbon dioxide laser.
The room will house four cameras for the test laboratories, data acquisition and control systems, waste gas and heat flux measuring devices, propane warning apparatus, propane delivery control, air and fuel mixing equipment, thermal radiation testing control and fire suppression equipment all under computer control.
Before any testing in the cells begins, materials and equipment are examined in the five supporting laboratories.
"The lab work helps us do an initial screening with bench-scale testing before conducting full-scale manikin tests," Lee said.
Getting materials ready for testing is the function of the materials preparation laboratory. It also has space necessary for future mission requirements.
The flammability testing laboratory will help study burning characteristics and thermal barrier properties of materials and equipment through a collection of bench-scale testing equipment, such as a vertical flame tester and radiant protective performance tester.
The combustion monitoring laboratory tests, evaluates and analyzes thermal processes and combustion by-products of field kitchen burners, tent heaters, water heaters and other support equipment for safe and efficient performance that meet joint service requirements. Testing equipment will include a vapor combustion furnace, drop tube furnace and porosometer.
The materials analysis laboratory will chemically analyze waste gases from the combustion of military fabrics and material through a gas-chromatograph mass spectrometer and other pieces of equipment.
The thermal protection testing laboratory will evaluate flame-retardant fabrics based on their flame and thermal protective performance at a heat flux simulating battlefield flame and thermal hazards. The performance is measured using skin sensors that can predict temperature changes and burn injuries on the human skin surface resulting from heat penetrating a fabric sample.
The thermal barrier test apparatus performs bench-scale testing using single or multiple layers of fabric samples 5 inches by 7 inches that are exposed to the heat flux of a flash fire for a specific exposure time.
The apparatus employs modern components and concepts such as an electro-mechanical shutter and linear position actuator to improve its operational precision and accuracy.
The portable flammability test apparatus is the most advanced fully automated and compact bench-scale system, Lee said. An unusual feature is that it can burn fabrics at multiple angles. Heat flux level, burn time and air gap between fabric and skin are computer-controlled, and skin temperature and burn injury prediction are fully displayed immediately after the test.
Lee said these capabilities provide information for efficient scientific research as well as quick procurement approval of military protective fabrics.
For more information about the Soldier Systems Center, please visit our website at: http://www.natick.army.mil.