Honda Power Unit Hardware & Software

[Albrodpul]

[Blackout]

If the fluttering noise occurs when power is reduced (closing throttle) it is more likely to be a blow off valve.

An onboard video with a bad cam but with interesting sounds... You can hear the blow off valve many times
But no clear wastegate sounds IMO
(and a very strange sound at 1:12)

[Albrodpul]

Real Honda Power Unit.

[NL_Fer]

Real Honda Power Unit.

https://pbs.twimg.com/media/CQYny5_WEAAolZq.jpg:large

omg did the turbo overheat and shrunk

[wuzak]

Real Honda Power Unit.

https://pbs.twimg.com/media/CQYny5_WEAAolZq.jpg:large

omg did the turbo overheat and shrunk

Must have got wet....

[Wazari]

Some teams are also the manufacturer so I don't follow the logic of the FIA is trying to cut costs to teams and not the manufacturers? The cost to design and produce the MGU-H units alone must be enormous and sadly much of this technology will never see its way into production vehicles if that is supposedly the end goal. I just don't understand this, also with the blending of these exotic fuels.

Also, what is the purpose of fuel usage restrictions. We're going to spend millions of dollars to make these cars go as fast as possible, oh BTW, there is a fuel usage restriction. Go ahead and spend hundreds of thousands of pounds to make the exotic fuels but you can only use so much a lap. How is that cost saving? This reactionary management style of the FIA is going to ruin F! IMO. I don't think people realize the cost of the hardware (IE. PU's, bodywork, etc.) is not that great compared to the R and D and initial production start up costs. Once you develop and eventually cast an engine block, the subsequent ones are small in cost relative to the cost incurred prior. Limiting teams to 4 or 5 PU's a season doesn't make sense to me either. Maybe I'm too old school, but something needs to change in the FIA's total view with regards to PU's.

Don't even get me started on tires...........

[ringo]

That's a very compact power unit. Too compact for it's own good. Looks like they will need a completely new engine next year IMO if they are to be competitive.

[Wazari]

Yes it's very compact, designed to fit the "size 0" concept bodywork. They will have a new PU for 2016 with radical changes.

[gruntguru]

The formula is fuel efficiency. Opening a wastegate wastes energy. The PU is designed to waste the absolute minimum energy. The design process carefully matches the turbine, compressor, piston engine, MGUH etc to avoid any situation where the wastegate would need to be opened. Boost control is primarily by MGUH. At full power the MGUK (120 kW max) is able to use all the energy produced by the MGUH so there is no need to open the wastegate, even if the ES is full.

The wastegate is massive. Way bigger than they would need for boost control. Suggests that its primary function is to reduce back pressure to zero in qualy' mode.

It's not as surface level as that. The engine is not operating under steady state. Also the PU is not designed to waste the minimum amount of energy, it's designed and programmed track to track to produce the most performance from 100Kg of fuel. We see this when the cars go in different power modes during a race.
If it was just black and white as aboslute minimum there will only be 1 mode of operation.

In one sense the engines are operated very close to steady state. Power transients are initiated by the drivers right foot and opening or closing the throttle has an immediate effect on boost by restricting intake air flow. Except for extreme power reduction, the rpm is maintained above 10,000.

At WOT, the airflow required for constant AFR is identical everywhere from 10,500 to 15,000 so the operating point on the compressor map moves vertically. The MAP required to maintain constant airflow must reduce as rpm increases so the turbine speed reduces - but only by about 10% for a 20% reduction in MAP. (rpm only varies by 15% - 20% with each gear shift)

[gruntguru]

. . . . The design process carefully matches the turbine, compressor, piston engine, MGUH etc to avoid any situation where the wastegate would need to be opened.

The above is a very bold statement, and i don't think we know the design philosophy behind these engines. Basically you are saying that a four way performance compromise is being made, and a variable that reduces compromise is being ignored because it wastes a few grams of burnt fuel.

Let me give you an example. The car is exiting a corner on a wet track. The driver applies the throttle. The boost starts to climb and the energy store is full. Traction is limited. Are you telling me that the MGUH will attempt to control boost by sending over 100hp to the rear axle when it is not needed?
That's just one situation where you simply tie up the whole system with a cumbersome and finicky way of boost control.
Put a waste gate in the situation and you have independent and precise control over you power unit and traction.

Couple of points there.
1. The lap would be planned to avoid the possibility of the ES being full at a point where excess MGUH energy becomes available. (Not that this scenario is likely anyway. It is not easy to keep the ES charged)
2. Boost control would never require a "sudden" increase in MGUH output - especially not 100 kW worth.
3. These engines are "AFR elastic". If for some reason MAP suddenly increases with a corresponding throttle command from the driver, the engine management will not simply increase fuel flow in line with the MAP increase. If fuel flow stays the same, the power ouput will remain very similar - like a diesel.

[gruntguru]

wastegating to so-called zero (or partial reduction of) so-called backpressure is interesting
the turbine is at max rpm and will try to evacuate the exhaust manifold ??
the mu-h motoring power lost by driving the turbine will be how much ? ..... and how/why ??
we might want to throttle the turbine but cannot ?

I think a radial inflow turbine will actually backflow (pressurise the exh manifold) rather than evacuate it due to centrifugal force. This may be an advantage for axial or mixed flow turbines in this scenario.

I tend to think they must be relying on blowdown energy to overcome turbine windage (and backflow) without pressurising the exhaust during the exhaust stroke.

[Javert]

Real Honda Power Unit.

https://pbs.twimg.com/media/CQYny5_WEAAolZq.jpg:large

Looks very prototypal

[GoranF1]

A member of neighborly forum Autosport,named @scarbs(not sure if Craig!?) has said that compressor is actually not axial,but normal radial and very small one tucked in the V of the ICE,and that basically Honda did same mistake Ferrari did last year and whit the fix of that area he expect the same jump Ferrari did this year.

[Tommy Cookers]

wastegating to so-called zero (or partial reduction of) so-called backpressure is interesting
the turbine is at max rpm and will try to evacuate the exhaust manifold ??
the mu-h motoring power lost by driving the turbine will be how much ? ..... and how/why ??
we might want to throttle the turbine but cannot ?

I think a radial inflow turbine will actually backflow (pressurise the exh manifold) rather than evacuate it due to centrifugal force. This may be an advantage for axial or mixed flow turbines in this scenario.
I tend to think they must be relying on blowdown energy to overcome turbine windage (and backflow) without pressurising the exhaust during the exhaust stroke.

to reduce to nominal 'zero backpressure' ie close to ambient .....
the exhaust proportion that must exit via the wastegate is about 50% or 60%

ie as the blowdown 'AC component' exhaust gas is not seperable from the default 'DC component' exhaust gas
(without some high-speed dedicated porting/valving device that is not permitted ?)
the blowdown energy available in the turbine region is only 40 or 50% of the normal level

constant AFR above 10500 rpm (ie reducing MAP and exhaust pressure) has good points (and bad)
as hollus has reminded me, shifting up gives a rev drop of about 20% in the middle gears and 13% in the highest gears

[hollus]

Yes it's very compact, designed to fit the "size 0" concept bodywork. They will have a new PU for 2016 with radical changes.

Do you mean radical changes as:
a) as having new things that no one has ever ran before,
or b) as in very different from their 2015 PU but more similar to what other teams are running?