New Engine Technology Will Boost Fuel Mileage

One design engineer who really loves the new ObamaAdministration fuel mileage requirements is Tom Hollis, who has invented a newdigital rotary control valve (DRCV) system that significantly boosts engineefficiencies.

Although many engine functions have become electronic inrecent years, engine thermal management has stubbornly resisted.

"Since Cadillac first installed a thermostat in 1914,basically all automotive engines have utilized an ‘analog' thermostat tocontrol the interaction of the engine with the radiator system," says Hollis."This system, while always incorrect, was inexpensive and provided adequateengine function."

The U.S. Environmental Protection Agency (EPA) establishes thestandard for engine thermal management. "There was no requirement for all thoseyears other than the 23C EPA cold-start test," says Hollis. "Everything wasfocused on doing that."

At -40C the thermostat still opens up even thoughthe engine is running cold. That happens because it's an analog circuit. Itoperates at +40C ambient and -40C ambient in exactly thesame way. The key item to remember is "Every BTU that exits through theradiator provides zero heat energy value," says Hollis.

"A main objective of our approachis to completely temperature map the engine, centered on thecombustion chamber, to determine actual known optimum engine operatingtemperatures under all driving conditions," says Hollis, a 25-year GMmechanical and electrical engineer who started a company called ElectronicEngine Temperature Control Systems in Medford, NJ.Engine combustion surface temperatures are measured by placing thermocouplesnear the exhaust valve and the intake valve.

"The ideal operating temperature for engine oil for maximumlubrication value is between 110C and 120C," says Hollis. "We regulate thebypass coolant circuit around the engine up to a maximum 120C, to always providea known optimum constant engine oil temperature – irrespective of eitherambient temperatures or engine load conditions." 

A test of the DRCV system in Timmins, Ontarioon a highly instrumented Jaguar showed that the system:

The economics of the system appear favorable. Hollis saysthe DRCV costs under $60 installed. Analog thermostats used on cars cost only$15 to $20, but the difference in initial cost will be made up very quicklywith savings on fuel and oil. Plus it's a quick way for auto OEMs to movecloser to the new federal mileage standards.

But why has it taken so long?

Hollis began working on the concept in 1994 when herevisited information obtained from his involvement with "vapor phase cooling"systems in the early 1980s.

Anyone familiar with technology development in Detroit, MI knows there is alot of inertia and a big "not-invented-here" syndrome. Hollis graciously says,"When you make a change there is always a warranty factor. Any time you make atechnology change you don't know what's going to happen. It's tough to increasecosts where the customer is not demanding it."

High gasoline costs, concerns about climate change and thenew federal mileage standards are all game-changers however.

Hollis says we will see the DRCV onproduction cars soon. "It probably will come in through Europebecause there are major programs on carbon dioxide reduction there." Two DRCVprograms are expected to launch this year with two specialty European carmakers, including Jaguar LandRover. Jaguar was close to an implementation sixyears ago, but Ford stopped the program because of financial issues not relatedto the DRCV.

One of the biggest obstacles for Hollis in the past dozen orso years was finding a funding partner. He hooked up last year withMileageMatrix Inc., a venture capital-based startup in Bellevue, WAthat wants to become a leader in carbon dioxide reduction approaches.

The technology will get lots of attention at the National PlasticsExposition June 22-26 in Chicago.The DRCV will be on display in the International Plastics Design Showcase,which is co-sponsored by Design News. It will also be shown by technologypartners Minco Tool and Mold (McCormick Place North Hall No, 60021) and DuPontEngineering Plastics (West Hall, No. 113011).

Hollis has had a relation with The Minco Group for more than20 years going back to his days at General Motors.

Minco built prototype tooling last fall for three plasticparts, which required significant work on mold design. "The tolerances on theparts are tight, and gating required a lot of work," says Gary Deaton, managerof marketing and manufacturing at Minco, which is located in Dayton, OH.

The biggest challenge was the parts needed to beperfectly round. DuPont assisted in testing to make sure that cavities werefilled precisely with glass-filled resins. Minco molded prototype parts onelectric Mitsubishi machines 300 tons and down.

The materials used are DuPont ZytelHTN high-performance polyamide for the valve body, tube and diverter.  The materials provide resistance tocontinuous exposure to hot long-life coolant up to 130C, and retention ofproperties with moisture.

"We had to be very sensitive to expansion and contraction becauseall surfaces are always ‘wet' and we needed a ‘fluid bearing' to preventsticking," says Hollis. "Zytel HTN PPAperformed well in these conditions, allowing us to take advantage of thelightweight nature of plastics and overall cost advantage over metals."

New system components are designed to provide continuous"digital" temperature control for both the engine and transmission. Thesecomponents will include the new DRCV, computer and heat exchangers. In the future, Hollis expects an electricwater pump might also be included. Hollis says the system works well oninternal combustion, hybrid and electric engines.

Not surprisingly, the DRCV from Hollis is not the only gamein town. Companies such as Carl Fredenberg, Bosch, Ranco, Valeo, Bosch,Visteon, Ford, Dana, EMP and Gerate-und Pumpenbau have all discussed somevariation of a technology to digitally manage engine temperatures. None hasgained commercial traction.

Ranco, a unit of Invensys, is the world's largest supplierof automotive coolant control valves and is rumored to be working on the ChevyVolt program.

Hollis gets kudos for sticking with his idea. He also sayshe has a strong intellectual property position with 19 U.S. patents,many covering control technology. Patents have also been granted or are pendingaround the world. MileageMatrix now has an exclusive license for all the patentrights established by Hollis over the past 15 years.

He also feels his development has a technology edge. Aunique grooved diverter outside diverter and valve body inside diameter providean important "non-stick" feature, for example.

New Engine Technology Will Boost Fuel Mileage A