Designing a Unique Lab for Advanced Military Vehicles
A new Army facility will support the warfighter with next-generation ground vehicles.
By Michael Kluger and Felt A. Mounce
The pace at which cutting-edge vehicle technologies are being developed to support the warfighter's needs continues to increase dramatically. Vehicles are being designed with experimental engines, alternative fuels, non-traditional powertrains, high-density energy storage capabilities, high-voltage electrical systems, armor plating, high-density electronics, navigational systems with complexity rivaling that of a fighter jet, and sophisticated battlefield communications.
Evaluating those systems and integrated vehicle platforms requires development, validation and commissioning so they are battle-ready and highly reliable. Both of these qualities are critically important and extremely challenging. The challenges are further compounded by the fact that military vehicles are operated at extremely high power levels, must be tested at extreme conditions, and that they typically contain new and experimental technologies.
To meet these challenges, the U.S. Army determined it needed a one-of-a-kind, fully integrated test facility, the likes of which had not been attempted before. The first step toward creating such a facility, to be located alongside the Army's existing TARDEC (Tank Automotive Research, Development and Engineering Center) laboratories in Warren, Michigan, was to prepare a specification defining the different laboratories and their testing equipment, operational requirements and facility infrastructure requirements.
To create the specification, the Army sought a collaborating research organization that would have a strong vision of where future vehicle technology is headed; a broad awareness of current vehicles and drivetrain systems; a deep grounding in vehicle and component testing and laboratory test equipment; and the ability to integrate multiple engineering requirements associated with mechanical, electrical and electronic systems. An additional requirement was that the specification be completed under a demanding, rigid schedule to be eligible for congressional funding. The new Ground Systems Power and Energy Laboratory (GSPEL) is expected to require two years to construct and become operational. The Army engaged Southwest Research Institute (SwRI), which has been involved with advanced and unique engine, vehicle and emissions research laboratories over many years, as a consultant to rapidly provide engineering support services for GSPEL.
The Army had a concept in mind but sought out SwRI to develop the demanding equipment and facility specifications necessary to embody the centralized, state of the art facility containing eight engineering laboratories. The goal was to create a facility to evaluate light transport such as HMMWVs to heavy combat vehicles such as military tanks with hybrid electric and fuel cell configurations and to evaluate components such as engines, transmissions, axles, electric motors, batteries, ultracapacitors, engine auxiliary systems, air filters, radiators and heat exchangers. To develop the specifications, SwRI assembled a team of 31 engineers with a wide variety of backgrounds.
For more than a half-century, SwRI has operated the Army-owned TARDEC Fuels and Lubricants Research Laboratory on the SwRI grounds in San Antonio. TARDEC Ground Vehicle Power and Mobility (GVPM) operates its primary facility at the Detroit Arsenal in Warren, where engines and vehicles are evaluated on dynamometers under extreme environmental conditions.
The team drawn from SwRI's automotive engineering divisions began by consulting with TARDEC engineers to gain an understanding of the vision for the laboratory, conceptualizing many options and eventually arriving at a preferred solution for each of the laboratories. Estimates of electrical, water, steam and gas utility requirements were developed for the overall building specification.
Detailed projections based on expected utilization, equipment specifications and discussions with TARDEC engineers revealed opportunities for efficiency gains as the team created a set of facility requirements. The requirements were provided to the U.S. Army Corps of Engineers to aid in the preparation of a bid request.
Green laboratory mandate
Beyond the efficiency gains that would be expected from a new laboratory, the Army today mandates that all new construction be certified under the "Silver" category of the U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED) Green Building Rating System™. LEED is a third-party certification program that encourages sustainable "green" building and development practices through universally accepted tools and performance criteria.
Furthermore, GSPEL will help expedite the integration of state-of-the-art hybrid-electric and fuel cell technologies into advanced military vehicles. In doing so, it will reduce fuel consumption, improve overall vehicle operation and employ the most efficient use of energy sources.
The new laboratory design expands the Army's technological thrust into cutting-edge power and energy management technology. The proposed facility will have labs and offices and related spaces for a staff of more than 50. Laboratories are provided for vehicle environment, power, electrical power architecture systems integration, electric components, pulse power and directed energy, thermal fluids, fuel cells and air flow filtration. Taken as a whole, the laboratory will be able to examine various vehicle systems as well as the entire vehicle.
Some of the selected equipment features include 11 AC electrically regenerative dynamometers with ratings from 2,500 foot-pounds (ft-lb) of torque and 14,000 rpm, up to 26,500 ft-lb and 1,000 rpm; a full-size vehicle chamber with environmental controls for temperature, humidity, and solar simulation; seven environmental chambers; three extremely high voltage and current power supplies; one of the world's largest calorimeters for testing radiators, engine coolers and transmission coolers; four air filter test stands of various sizes with combined dust media insertion; and four fuel cell test stands.
The design team projected the facility's electrical usage over 30 years, based on various dynamometer operating schedules, environmental chamber thermal cycles, power supply duty cycles, calorimeter test procedures and air filtration testing requirements. The projected electrical service was determined to be 4.7 megawatts (MW), with yearly power consumption of more than 2 million kilowatt-hours. Cooling water needs were projected at 2,500 gallons per month. Power supplies to the facility will be rated to 800 volts DC and 1,000 amps. The environmental air handling system will be able to flow 175,000 cubic feet per minute, with 90 tons of heating and cooling, to control air temperature and humidity.
Meeting LEED certification standards for such a facility is extremely challenging. Therefore, the SwRI engineering team created methods for quantifying LEED improvements, enhancement and solutions, and for exploring multiple equipment and energy-related issues. Some of those issues involved different dynamometer operating power scenarios during electrical motoring and regenerative operating modes; dynamometer energy recovery; electrical motor operation in off-peak conditions; and precision power supply charge-discharge cycles. For each lab within the facility, the dominant energy-consuming or energy-producing items were selected for individual study. For example, dynamometer efficiency was studied at various partial-load conditions to produce accurate electrical consumption estimates for the facility.
Broad-based design capabilities
The creation of a specification for a facility as broad and far reaching as GSPEL was an extremely challenging task. The GSPEL facility requires equipment to work at levels that are unprecedented in today's engineering laboratories and, in many cases, will represent the largest such capabilities in the world. Satisfying such capabilities is a requirement in order to allow for testing of future military vehicles which will have capabilities well beyond those of current vehicles. The SwRI team was able to help the Army define and then integrate a wide range of laboratories and equipment into a single facility that will allow vehicle testing and development across demanding test conditions and in dramatically reduced time. This, in turn, will allow the Army to continue the development of future generations of military vehicles, integrating current and alternative vehicle propulsion, power generation, energy storage, power management and control systems for current and emerging classes of vehicles that are both wheeled and tracked, and manned and unmanned.
The SwRI team defined and prepared this specification using its broad experience in testing engines, transmissions, axles, electrical power components and vehicles over the past 60 years. This experience has been enhanced with real-world knowledge based on operating more than 240 dynamometers at its San Antonio facility, which is believed to be the largest dynamometer grouping of its kind in the world. In addition, much of this testing is extremely challenging as it involves the next generation of powertrain components and vehicles that typically incorporate advanced technologies. Testing these types of components requires the use of intensive engineering to provide creative and innovative approaches and solutions, whether by modifying existing testing equipment or fabricating custom equipment.
The development of the GSPEL specification involved the generation and integration of massive amounts of information associated with extremely high-power electrical equipment, high-speed rotating equipment, very high voltage and amperage levels, extreme heating and cooling, humidity control and massive air-flows. Complementing this equipment was an extensive suite of instrumentation for measuring torques, speeds, pressures, flows and temperatures.
Acting as the client's advocate by creating test stand and test facility specifications is a long-standing service that SwRI has provided for more than 30 years. By its very nature it is a challenging and demanding discipline because of the breadth of technologies and the wide range of operating conditions that engineering testing involves. Because of the many types of components SwRI is involved with on a daily basis, it provides such specifications and test stands for applications involving the next generation of heavy-lift helicopter gearboxes, submarine propulsion systems, advanced engines used in military vehicles, drilling motors used in oil rigs, transmissions used in 18-wheel trucks and precision hydraulics used in high-pressure applications.
The document that SwRI prepared was integrated into a request for propoal by the Army and advertised for a design-build contract to construct the GSPEL laboratory. Multiple bids were received and are being reviewed to determine if they meet the specified facility and equipment requirements. Upon completion, the project will be awarded and construction should begin in the very near future.
Published in the Spring 2009 issue of Technology Today®, published by Southwest Research Institute. For more information, contact Joe Fohn.