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SwRI "super cell" evaluates heavy-duty engines by simulating real-world environmental conditions

San Antonio — June 23, 2006 — Southwest Research Institute® (SwRI®) has developed a "super cell" to evaluate the effects of altitude and other environmental conditions on performance and pollutant emissions of heavy-duty engines, with interactions of fuels, lubricants and catalysts.

"Regulatory groups worldwide are concerned that pollutant limits demonstrated in currently prescribed test procedures may be exceeded in day-to-day, real-world applications," says Terry L. Ullman, assistant director of the SwRI Engine and Emissions Research Department. The Environmental Protection Agency bolstered assurance that emissions levels are held in check by introducing not-to-exceed (NTE) emission limits that apply to in-use operation over a range of environmental conditions encountered by trucks and other engine applications.

Conditions within not-to-exceed (NTE) compliance zones are readily available with the super cell, which applies various altitude conditions, in combination with a range of temperatures and humidity levels, to engines of 100–750 horsepower.

"Although these conditions can be assessed to some degree in the field, engine development and calibration efforts are better performed and validated under tightly controlled conditions," says Ullman. "By combining the environmental conditions seen throughout the world into an engine test cell, we can help manufacturers and suppliers meet the challenges of more stringent emission limits for hydrocarbons, carbon monoxide, oxides of nitrogen and particulates."

Although the super cell is designed to ensure NTE compliance, it also can be used to optimize engines for fuel economy and performance at conditions not easily achieved in the laboratory. Combining this capability with precise instrumentation and engine operation, SwRI helps manufacturers evaluate and optimize how their engines, fuels and lubricants will operate at high altitudes, such as those in Denver and Mexico City, as well as at lower altitudes. Devices that control emissions or improve performance can also be quantified.

The ability to evaluate engines at high and low altitudes using a consistent set of instruments, with the same engine setup and control, at the same location, also relieves concerns about lab-to-lab variability. The super cell uses a full-flow, constant volume sampling, gaseous emissions bench and particulate measurement system to provide emissions data compliant with current and 2007+ highway engine regulations, as well as current and future non-road engine regulations. The system can accommodate steady-state and transient engine operation at altitudes up to 12,000 feet above sea level, along with additional variations in temperature and humidity conditions to investigate emissions levels and engine performance for markets outside the NTE envelope.

For more information about the super cell, engine manufacturers, fuel and lubricant manufacturers, catalyst suppliers and regulatory agencies should contact Daniel Stewart at (210) 522-3657. 

Editors: An image to accompany this story is available at

For more information contact Maria Stothoff at (210) 522-3305, Communications Department, PO Drawer 28510, San Antonio, TX 78228-0510. 

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