Smaller gets bigger

Size, they say, matters—but in this case not as you think. Available space under the hood is in ever-shorter supply as cars get smaller and other components elbow in on traditional ones; engineers and designers are constantly challenged to fit better function into less space. Sometimes the only way to get there is to reduce the size of the component.

Two products recently announced by Denso Corporation and already on the road provide good examples of what the future of cooling may hold for all manufacturers: new materials, reduced dimensions and high thermal transfer efficiency.

The new radiator in the Lexus GS is now 40 percent smaller and lighter than the previous one. The company says the core is only 16 mm wide, replacing the older 27 mm unit. Inside, some proprietary metallurgy plus improved design of the fins and tubes combine to yield better heat exchange from a smaller unit.

As the Toyota and Lexus model lines expand or are redesigned, Denso says it will use the technology to replace their 36 mm radiators with a 27 mm model, and also provide an 11.5 mm version as well – that last one will be less than half an inch thick.

The other cooler is the company’s foray into a new market: EGR coolers for gasoline engines, and Denso says they’ve got the smallest one on the market.
Exhaust gas recirculation is used mainly to reduce tailpipe emissions; a small portion of the exhaust stream is recirculated back into the intake manifold to be mixed with the new fuel charge in the cylinder and then reburned. EGR is widely used on many engines from many makers.

The only snag is that in some engines, the recycled exhaust remains hot enough to cause a number of problems within the cylinder. Although not everybody does it, cooling the EGR stream can be beneficial, and the new unit routes the exhaust gas through a small heat exchanger connected to the liquid cooling system. The flow of engine coolant absorbs heat from the gas and carries it up to the radiator.

The company promotes this new unit as an answer to increasingly stiff emission rules worldwide and diminishing space under the hood. For now, the EGR cooler is on the new Camry and what North America knows as the Prius C —elsewhere it’s the Aqua.
Neither of these products are unique except perhaps for their size and equivalent function, and many competitors are working on the same ideas right now. But these and others are significant as an evolutionary step in the cooling industry.


The Mobile Air Conditioning Society’s blog has been honored as the best business to business blog in the Automotive Aftermarket by the Automotive Communications Awards and the Car Care Council Women’s Board!

When having your mobile A/C system professionally serviced, insist on proper repair procedures and quality replacement parts. Insist on recovery and recycling so that refrigerant can be reused and not released into the atmosphere.

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The 33rd annual Mobile Air Conditioning Society (MACS) Worldwide Training Conference and Trade Show, Be the Best of the Best will take place February 7-9, 2013 at the Caribe Royale, Orlando, FL.




About macsworldwide

Mobile Air Conditioning Society (MACS) Worldwide Founded in 1981, MACS is the leading non-profit trade association for the mobile air conditioning, heating and engine cooling system segment of the automotive aftermarket. Since 1991, MACS has assisted more than 600,000 technicians to comply with the 1990 U.S. EPA Clean Air Act requirements for certification in refrigerant recovery and recycling to protect the environment. The Mobile Air Conditioning Society (MACS) Worldwide’s mission is clear and focused--as the recognized global authority on mobile air conditioning and heat transfer industry issues.
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