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Rest In Peace, old friend, your work is finished.......
If you want on or off the DIESEL ”KnOcK” LIST just FReepmail me........
This is a fairly HIGH VOLUME ping list on some days......
Posted on 08/15/2007 8:43:04 AM PDT by Red Badger
Depending on drive cycle......
Initial simulation studies of a prototype heavy-duty air-hybrid engine being developed by engineers at Volvo Powertrain, UCLA and Sturman Industries show a 4-18% improvement in fuel economy over a wide range of driving cycles. The amount of improvement depends on the cycle.
The addition of a low-temperature EGR circuit could boost that improvement by another three to four percentage points, according to the research team. The goal of the project, co-funded by the DOE, is to develop and demonstrate a heavy duty air-power-assist (APA) engine for a refuse vehicle with a 15% improvement in fuel efficiency and with emissions that meet the 2010 regulations. (Earlier post.)
Hyungsuk Kang from Volvo Powertrain presented the current results of this APA project at the DEER (Diesel Engine-Efficiency and Emissions Research) conference in Detroit.
The APA engine uses braking energy to work as a compressor, pumping compressed air into an on-board air tank (Air Compressor mode, or AC mode). During acceleration, the stored compressed air powers the engine—with or without burning diesel fuel—to get up to speed, or until the compressed air is depleted (Air Motor mode, or AM mode). Once the vehicle is moving along the engine converts back to a conventional diesel engine.
During engine acceleration, the high boost pressure also helps reduce the emissions of particulate matter. In addition, smaller quantities of fuel burned in each cylinder lead to lower peak temperatures, resulting in lower NOx formation. The APA technology also facilitates greater use of the engine brake, which in turn helps save fuel and reduces the frequency of brake service with its associated costs.
The APA engine is based on an 11-liter in-line six-cylinder diesel engine modified with a hydraulic valve actuator system from Sturman, an Amplifier Piston Common Rail System (APCRS) from Bosch, and a control system developed by UCLA. Compression ratio for the engine is 16:1. (Tsu-Chin Tsao, professor of mechanical and aerospace engineering at the UCLA Henry Samueli School of Engineering and Applied Science and his students are also working with Ford on a prototype light-duty air-hybrid system based on a 2.5-liter V-6.)
The variable valve actuator and the mode-switching controls are key enablers for the air-hybrid—in AC mode, the engine switches to a two-stroke mode, according to Kang. Other critical elements are the engine valve stem seals and external switching valves.
The air tank is designed to operate at 20 bar maximum pressure. Currently, in the experimental work, the system works at just 13 bar. The air tank also has a relief valve that can trigger at 15 bar.
Rest In Peace, old friend, your work is finished.......
If you want on or off the DIESEL ”KnOcK” LIST just FReepmail me........
This is a fairly HIGH VOLUME ping list on some days......
KnOcK!........
Horsepower, please....
This and the hydraulic hybrid make good sense for heavy stop and go vehicles such as garbage trucks and city busses. In those cases batteries are too expensive.
One of those “why didn’t I think of this before” things. Pretty interesting. I’ve heard of using compressed air (from applying to brakes) to give a vehicle a boost, but the boost was provided by a separate motor. This system boosts the actual engine that powers the car. Nifty!
At 671 cubic inches, I'm sure there's aplenty....
At least it might quiet that horrible Jake Brake noise.
I like that sound!.........It’s when you don’t hear it that should worry!.......
There’s no economic substitute for cubic inches.
That guy used to look old. Now he looks to be quite young. WUWT?
Might as well ask for the weight, cost and revs while you’re at it.
It’s the hat.
“At least it might quiet that horrible Jake Brake noise.”
.....I applaud cities where they’ve outlawed jake brakes....we moved in 2006 because we lived near an intersection where the cops refused to enforce noise ordinances....I’m an ex Teamster and was in heavy trucks in the Army and feel that jakes are un necessary and a public nusiance.
Yep!! He did look lke an ld fart to a 12 yr old kid watching Laugh-In!!!
It's an old residential area, flat as a billiard table, yet some ftruckers insist on jack breaking.
I’m surprised it only runs at about 300 psi...
Cool....where can I get an add-on kit for my Dodge Cummins 4X4.
I want one in a <4000lb stationwagon/minivan (w/AWD).
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