Volvo reinvents (sort of) a 1960s chev concept...

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http://articles.sae.org/14885/

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Volvo is using a blast of compressed air to boost torque delivery and exorcise turbo "lag" of its new D5 diesel engine. It's a comparatively simple technology solution that works very effectively, as company engineers demonstrated to Automotive Engineering on a lengthy and often demanding test drive of the D5-powered V90 station wagon in southern Spain.

Volvo has dubbed the novel, heavily patented diesel air-delivery system "PowerPulse." It serves as a cost-effective alternative to using a 48-V hybrid system with electrically-driven turbocharger or supercharger to rapidly spin up turbines at low engine revs.

Volvo powertrain engineers spent more than three years developing PowerPulse, on the same critical path as the D5 engine. The 2.0-L 4-cylinder direct injected diesel delivers a claimed 173 kW (232 hp) and 480 N·m (354 lb·ft). A lower-powered D4 version producing 140 kW (188 hp) and 400 N·m (295 lb·ft) without PowerPulse also is available.

A simple, compact system

On the road PowerPulse literally blows into action, helping the V90 wagon accelerate from standing start to 100 km/h (62 mph) in 7.2 s which, bearing in mind the car’s power output and 1817-kg (4006-lb) curb weight, is brisk but not exceptional. The car’s automatic transmission is an 8-speed Aisin. No manual gearbox is offered.


Back in Uni, when I had access to the SAE microfiche cache (yes that long ago).

One of the SAE papers that I loved was a Chev concept test car which had a low volume compressor, charging a fibreglass sphere in the trunk, then under acceleration, using it through a venturi ejector and blow through carb to provide effective supercharging on demand.

Lots of boot space taken up with what was an essentially bootstrapped design...but this new Volvo thing is scarcely unique in concept.
 
According to the article they don't use the compressed air tank to blow air into the intake, like the Chevy system you mentioned - they blow it into the exhaust, to spool the turbo. So to me it seems like the only similarity is the compressed air tank.
 
If I'm understanding it correctly, then PowerPulse is just a quick thing, to beat turbo lag. So the lower power version is just a ploy to get one to buy the better tech. If I'm understanding it correctly.

Interesting concept. I'm a bit surprised though, I thought variable vane tech had "fixed" turbo lag. Maybe it was still there but I got used to it, when I had a turbo.
 
Originally Posted By: NateDN10
According to the article they don't use the compressed air tank to blow air into the intake, like the Chevy system you mentioned - they blow it into the exhaust, to spool the turbo.


Why not blow it into the intake side?

Or have a jet that blows against the tips of the compressor wheel... kind of like a Penton turbine?
 
This has emissions implications, of course. For a Diesel, running "over" (more air then needed to support full combustion) leads to less particulates then running "under".

Remember, in the automotive world, everything has to be done cheaply. That means actuators are on/off whenever possible, and not incremental (e.g. PWM controlled) if possible. So a simple on/off air dump actuator in the turbo exhaust path is the simplest way to go. All other sensors and programming would remain the same.

Also, back to emissions, dumping air in the intake would lead to a backpressure situation that would momentarily interrupt airflow once the pressurized air is cut off. That would lead to a momentary high emissions event. A PWM controlled actuator could better control that, see previous about cost engineering.
 
Quote:
Finally possessing a platform the delivers the structure and chassis dynamics necessary to deliver premium-class ride quality, Volvo development engineers are now focusing on NVH and other details, stated Product Manager Lars Lagström. He contrasted the company's Geely ownership to the years under Ford, when "there were always squeezed budgets" and "it was short-term everything." Ford, Lagström noted, "never understood Volvo."


That totally matches my understanding of Ford.
 
Tangent.

^^^

interesting. the previous gen s60 I believe was designed before ford bought them. the early s60s were solid, bank-vault like. I had an 01 and an 05. The 09, which was the final year of that body, has a lot of cost cutting. I wonder if ford played a role there-- interior glues, material assembly, and increased body panel gaps are obvious. I test drove a '14 before I bought the 09 and it was a further step backward. It was solid and well built, but the plastics were less supple and the cabin noise had increased noticeably. Even the degraded '09 was quieter and felt more hefty/solid. It did not drive or feel like a volvo to me, more like an accord, especially with the road noise and feel, which was responsive, but felt very lightweight and bouncy - not a typical volvo feel to me. So we went with the '09.

don't get me wrong, the 14 was by no means a bad car--- but compared to the previous gen it seemed to have lost some of the driving characteristics that I personally enjoy.
 
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In the 90s when I was into turbos, someone was telling me of a drag racer in the 70s or 80s who was running a compressed air tank and pre-spooling his turbos. The drag racer was a car book author (not of turbos though). I just don't remember his name now.
 
Oh for sure implications to emissions are included. I'd put money on Volvo using the system as an emission strategy also. Small things like the throttle-shut rich condition known and loved by all. The fuel present could be exploited to keep the turbine spun, while also reducing the downstream rich condition. Fresh oxygen, without having to pass through the CC, could enhance the catalyst performance also.
 
https://www.google.hr/url?sa=t&source=web&rct=j&url=https://www.groupe-psa.com/en/newsroom/automotive-innovation/hybrid-air/&ved=0ahUKEwiT3eDU98_UAhXPzRoKHYv6C8wQFggZMAA&usg=AFQjCNHt1CMARhrQ2jISyElm-OX1dU54og&sig2=MFt_ZrqSiEJxxQGIn9vXBw

PSA is making compressed air hybrid.
 
Originally Posted By: NateDN10
According to the article they don't use the compressed air tank to blow air into the intake, like the Chevy system you mentioned - they blow it into the exhaust, to spool the turbo. So to me it seems like the only similarity is the compressed air tank.


that's why I said "sort of"...cosider the turbo as a lever...push the intake end, or push the turbine.
 
Seems like the Focus RS has something similar between shifts where it dumps fuel during the exhaust stroke - intentional backfiring - which keeps the turbo spun up for when the driver grabs the next gear.
 
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