Air Management System for Heavy Duty Vehicles
How it Works
What became Enviro-Cool, Inc. started in 1985 with the development of a method to clean cooling systems in liquid cooled internal combustion engines while the engine was operating. At this time, the only commercial method was to drain and flush the cooling system, add a mixture of acidic cleaning chemicals, and run the engine for a specified period of time. Then drain and flush several times to remove the coolant mixture which was very toxic and difficult to dispose of. This process was time consuming and expensive. Consequently, very few fleet operators cleaned the cooling systems of their engines.
It had been known for many years that 50% of all premature engine failure was due to problems in the cooling system. In addition, about 80% of these failures was due to contamination of the cooling system, that being scale formations, hotspots, coolant degradation, etc. This contamination caused cracked engine heads, rust, engine overheats, lubricating oil degradation, etc.
In 1992 a patent was granted on the Enviro-Cool cooling system cleaning filter, U.S. Patent #5050549. Foreign patents were granted in 13 countries.
The unique features of the Enviro-Cool Cleaning Filter was the simplicity. A standard cooling system filter cartridge was charged with a chemical package containing alkaline chelating cleaners plus standard protecting chemicals instead of acid cleaners. In this way the alkaline cleaners could be left in the cooling system until the cleaning process deleted them because there was no danger of damaging the metals and other materials in the cooling system. This process took about 10,000 miles or one month. After this time the Enviro-Cool cleaning filter was removed and thrown in the trash since none of the chemicals in the filter were toxic or banned by the EPA..
The advent of the EPA mandated pollution requirements on heavy duty vehicles in October, 2002, made the use of the cleaning filter even more important and helpful to the fleet operator.
The addition of 30% more heat load into the cooling system caused by exhaust gas recirculation (EGR) exacerbated problems with coolants; rapid coolant breakdown, faster scaling, gloxalates, etc. The Enviro-Cool cleaning filter could handle these problems but the EGR caused much more additional misery. For more information visit the Enviro-Cool website at www.envirocool.us.com or www.ecfilter.com and click on Technical Information.
In 1999, the Technology and Maintenance Council (TMC) of the American Trucking Association and the Society of Automotive Engineers (SAE) asked the Commercial Vehicle Group (COMVEC) to form a task force to investigate the effects of EGR systems on an anticipated increase in cooling system heat load. The task force suggested that an additional heat load of 15% to 30% could be expected. It predicted problems with under hood temperatures causing electrical and electronic issues, positioning of fuel filters, higher cab temperatures, etc.
At this time Enviro-Cool decided to investigate possible opportunities in solving these problems.
It all began in early 2000 by calculating simple heat balances to find out about the severity of the additional cooling system heat, The heat balance showed the problem very quickly.
A heavy duty vehicle, preEGR, traveling at 60mph getting about 7 mpg, produces 1,500,000 Btu’s per hour with 1/3 to power, 1/3 to exhaust, and 1/3 to the cooling system. Test data showed that an EGR equipped engine provides approximately 680,000 BTU,s per hour from the radiator heated ram air reinforcing the 60,000 BTU’s per hour developed under hood by the EGR, turbo, exhaust manifold, etc. This means that the cooling system has an additional heat load of 180,000 Btu’s (680,00 minus 500,000) to contend with. Enviro-Cool’s solution was to divert the radiator’s heated air from the engine compartment. This was accomplished by using electric squirrel cage fan motors to turn the ram air 90 degrees after passing through radiator and out the side of the hood and using cowl air induction (used by race cars) to provide ambient air at the rear of the hood moving through the engine compartment toward a venturi exit in the radiator exit duct.
Actual truck testing was in order at this time. Enviro-Cool purchased an EGR equipped 2004 Freightliner Daycab with a 375 HP 10 speed Detroit Diesel for tests. Wind tunnel tests were conducted by Jacobs Engineering at the Ford Motor Company facility, Dearborn, MI. Results showed a 130 degree F reduction in under hood temperature at the turbo- 297 degrees to 167 degrees with an ambient temperature of 100 degrees F at 60 mph.
During these tests it seemed there was considerable reduction in fuel consumption with the Enviro-Cool modifications.
Next, TMC/SAE fuel economy tests were conducted by Claude Travis & Associates in Michigan. The first test results showed a 4.85% fuel economy improvement. After some modifications a few weeks later a second fuel economy test showed a 7.24% fuel economy improvement. We feel more improvement in fuel economy will ultimately be available.
When running the fuel economy tests, it was noticed by everyone that the newly named Air Management System had much less fan noise. A test by Enviro-Cool showed a 16 decibel reduction in overall noise and a 50% reduction in fan noise. It is anticipated to have SAE noise level tests run in the near future.
A patent was applied for on the Enviro-Cool Air Management System which was granted in 2009. Patent # 7537072.
George R. Sturmon Founder, Enviro-Cool