Honda Power Unit Hardware & Software

[Tommy Cookers]

I was thinking in terms of stator magnet arrangement in the ERS motors (MGU-H and MGU-K). It seemed like if Halbach arrays were to be used, we'd have 'boosted' magnetic flux inside, increasing the efficiency of the motor. That said, probably a lot of F1 teams are already utilising this effect.

presumably you ....
intended to write rotor magnet arrangement .... and .....
have read the links posted by Greg Locock in the thread 'Brushless dc motor diy' in Engineering Projects section ....
telling us via 'Halbach' type design 'air gap magnetic flux was effectively sinusoidal' (nearly eliminating one type of loss)

[Tommy Cookers]

In a way, because you reduce back pressure with higher turbine speed, which alters the pressure waves and how they reflect in the exhaust system. Since the H is also coupled to the compressor, compressor speed and thus intake pressure waves are altered....

untrue
because the pressure wave behaviours are independent of pressure

[Dee]

just wondering if Honda are bringing their upgrades after the summer break, the same as Mercedes?

[godlameroso]

In a way, because you reduce back pressure with higher turbine speed, which alters the pressure waves and how they reflect in the exhaust system. Since the H is also coupled to the compressor, compressor speed and thus intake pressure waves are altered....

untrue
because the pressure wave behaviours are independent of pressure

They are dependent on flow, and if you reduce or increase backpressure you alter those flow characteristics, and in turn the pressure waves that reflect back and forth. Flow entrains flow.

[ryaan2904]

I dont know what you mean by "core engine characteristics" but yes that's what the different strat modes and other switches do, change how much mgu's recharge (generator) vs adding to output power (motor).
This we know happens, how it happens is the top secret magic.

Core engine characteristics as in combustion characteristics because by altering the H unit's speed, you're affecting the in cylinder pressure right? and if they are affected won't the compression ignition characteristics also change?

In a way, because you reduce back pressure with higher turbine speed, which alters the pressure waves and how they reflect in the exhaust system. Since the H is also coupled to the compressor, compressor speed and thus intake pressure waves are altered. Furthermore, since Honda uses a bypass system compressor output can affect exhaust gas temperature and volume/density.

Do you mean that 'CAC exhaust bypass'? Can u explain please what that does?

[godlameroso]

Core engine characteristics as in combustion characteristics because by altering the H unit's speed, you're affecting the in cylinder pressure right? and if they are affected won't the compression ignition characteristics also change?

In a way, because you reduce back pressure with higher turbine speed, which alters the pressure waves and how they reflect in the exhaust system. Since the H is also coupled to the compressor, compressor speed and thus intake pressure waves are altered. Furthermore, since Honda uses a bypass system compressor output can affect exhaust gas temperature and volume/density.

Do you mean that 'CAC exhaust bypass'? Can u explain please what that does?

It increases mass flow to the turbine increasing recovery potential. Instead of using a compressor bypass that vents to the atmosphere, or back into the intake plenum, it is routed to the turbine to give the turbine wheel an extra push which can then be harvested by the MGU-H. It also has the benefit of lowering the temperature of the turbine components by providing cooler air from the compressor, improving reliability of components.

The trend in aviation is to use bigger engines because it's more efficient to have big fans that move a lot of ambient temperature air at a slower velocity, than it is to have jets that move a little bit of air really fast. Likely this design consideration was absorbed into the Honda engine from their aircraft engineers. They may have figured that using an oversize compressor with a bypass and electronically controlled turbine wastegate offered interesting opportunities, seems to be paying off for them.

If the compressor keeps the engine fed, and the turbine spinning, then in effect it reduces the backpressure created by the turbine to the combustion process. Instead of absorbing crank power it's absorbing excess compressor power, which can then be harvested and used later or to save the battery the inconvenience of spooling up the turbo in places. Probably other strategies I missed, I'm just some guy.

[PlatinumZealot]

I was thinking about, application of Halbach array to arrange the permanent magnets inside the ERS motors

What for?

If you missed my suggestion as to a purpose - a couple of posts back up the page - is that it?

I was thinking in terms of stator magnet arrangement in the ERS motors (MGU-H and MGU-K). It seemed like if Halbach arrays were to be used, we'd have 'boosted' magnetic flux inside, increasing the efficiency of the motor. That said, probably a lot of F1 teams are already utilising this effect.

Ok. The magnets inside the MGUH is already arranged for the highest density magnetic flux.

There is not much imorovement to find electrical efficiency wise in these cars. Limiting returns. A lot of the effort goes into weigh reduction, cooling, control and reliability. In other words don't expect sizeable power increases from ERS upgrades, but you can expect better reiliability and better control modes.

[AR3-GP]

What for?

If you missed my suggestion as to a purpose - a couple of posts back up the page - is that it?

I was thinking in terms of stator magnet arrangement in the ERS motors (MGU-H and MGU-K). It seemed like if Halbach arrays were to be used, we'd have 'boosted' magnetic flux inside, increasing the efficiency of the motor. That said, probably a lot of F1 teams are already utilising this effect.

Ok. The magnets inside the MGUH is already arranged for the highest density magnetic flux.

There is not much imorovement to find electrical efficiency wise in these cars. Limiting returns. A lot of the effort goes into weigh reduction, cooling, control and reliability. In other words don't expect sizeable power increases from ERS upgrades, but you can expect better reiliability and better control modes.

The power is capped at 120kw. There was never going to be a "power increase".

What teams can improve is providing a unit with more accessible power. (Better harvesting and longer deployment at the power cap)

[DutchPanther]

I was thinking in terms of stator magnet arrangement in the ERS motors (MGU-H and MGU-K). It seemed like if Halbach arrays were to be used, we'd have 'boosted' magnetic flux inside, increasing the efficiency of the motor. That said, probably a lot of F1 teams are already utilising this effect.

Ok. The magnets inside the MGUH is already arranged for the highest density magnetic flux.

There is not much imorovement to find electrical efficiency wise in these cars. Limiting returns. A lot of the effort goes into weigh reduction, cooling, control and reliability. In other words don't expect sizeable power increases from ERS upgrades, but you can expect better reiliability and better control modes.

The power is capped at 120kw. There was never going to be a "power increase".

What teams can improve is providing a unit with more accessible power. (Better harvesting and longer deployment at the power cap)

So basically increasing the efficiency of the unit.

[Tommy Cookers]

The power is capped at 120kw. There was never going to be a "power increase".

the motor power is not capped at 120 kW
the DC line motor power is limited to 126.3 kW so if efficiency is 95% mechanical power added to crankshaft is 120 kW

if efficiency is more than 95% the mechanical power added is (legally) 'increased' to more than 120 kW

similarly gains can be made in generating

[Tommy Cookers]

... in effect it reduces the backpressure created by the turbine to the combustion process .....

there is no (turbine) "backpressure to the combustion process"
exhaust is inherently a choked process - ie the backpressure has no effect on the power stroke

[PlatinumZealot]

I was thinking in terms of stator magnet arrangement in the ERS motors (MGU-H and MGU-K). It seemed like if Halbach arrays were to be used, we'd have 'boosted' magnetic flux inside, increasing the efficiency of the motor. That said, probably a lot of F1 teams are already utilising this effect.

Ok. The magnets inside the MGUH is already arranged for the highest density magnetic flux.

There is not much imorovement to find electrical efficiency wise in these cars. Limiting returns. A lot of the effort goes into weigh reduction, cooling, control and reliability. In other words don't expect sizeable power increases from ERS upgrades, but you can expect better reiliability and better control modes.

The power is capped at 120kw. There was never going to be a "power increase".

What teams can improve is providing a unit with more accessible power. (Better harvesting and longer deployment at the power cap)

MGUH is not limited as far as I remember.

[AR3-GP]

Ok. The magnets inside the MGUH is already arranged for the highest density magnetic flux.

There is not much imorovement to find electrical efficiency wise in these cars. Limiting returns. A lot of the effort goes into weigh reduction, cooling, control and reliability. In other words don't expect sizeable power increases from ERS upgrades, but you can expect better reiliability and better control modes.

The power is capped at 120kw. There was never going to be a "power increase".

What teams can improve is providing a unit with more accessible power. (Better harvesting and longer deployment at the power cap)

MGUH is not limited as far as I remember.

Apologies, I misunderstood your post. I thought you were referring to the MGU-K.

[godlameroso]

... in effect it reduces the backpressure created by the turbine to the combustion process .....

there is no (turbine) "backpressure to the combustion process"
exhaust is inherently a choked process - ie the backpressure has no effect on the power stroke

It does have an effect on cylinder scavenging and filling, which are crucial to the power stroke. As the power stroke is entirely dependent on those intermediate events, much like combustion itself is determined by intermediate reactive radicals in the fuel.

On a completely unrelated note, cooling exhaust gas could have the benefit of increasing the mass density of said gas. Afterall a limiting factor to a compressor is that the air is compressed to a point that the heat generated lowers density and with it the ability to do work. That is why intercoolers make more power, they increase the air density improving cylinder filling.

Perhaps one of the reasons fuel is necessary to power an engine is the fact that the density of combusted gases having CO2, NOx, and other molecules that are more dense than air means that you don't lose much gas density despite the high temperature. I imagine if we just heated air, it's density would be so low that there would be little to no power generated.

[gruntguru]

In a way, because you reduce back pressure with higher turbine speed . . .

I don't think this is right. Higher turbine speed = higher back pressure.