Honda Power Unit Hardware & Software

[bergie88]

Cosworth expected something around 120 HP from the MGU H but only around 600 from ICE

http://i.imgur.com/pMHl9vv.jpg

How do you get the 120 bhp from this picture? When it is true it is impressive for sure.

[gruntguru]

Cosworth expected something around 120 HP from the MGU H but only around 600 from ICE

http://i.imgur.com/pMHl9vv.jpg

How do you get the 120 bhp from this picture? When it is true it is impressive for sure.

It is the gap between the dashed line and the solid white line above it.
The gap between the dashed line and the solid red line is the MGUK maximum 160 hp added to the dashed "crankshaft power only" line.

[bergie88]

Cosworth expected something around 120 HP from the MGU H but only around 600 from ICE

http://i.imgur.com/pMHl9vv.jpg

How do you get the 120 bhp from this picture? When it is true it is impressive for sure.

It is the gap between the dashed line and the solid white line above it.

Ah I see, I was focussing more on the red and white solid line. What do you think grunt, is this possible? I've seen several calculations on the forum but they were never as high as 120 bhp if I am correct.

[NL_Fer]

I believe most mgu-h power is recovered during the last part of the straights, when the ice is running 12000rpm. The higher the revs, less time is available in the cilinder to burn the fuel, and more heat is wasted. Here the turbo and mgu-h come in to collect this wasted energy.

But the more energy is recovered, the hotter the turbo will get, to a point they have to let the exhaust gasses released, just to prohibit turbo becoming to hot.

Macca asked for a size zero package, now heat is a problem.

Just look it the other cars, the all route fresh intake air, to the area around the turbo (turbine) and i believe it's a task of aero departement to facilitate this.

[Tommy Cookers]

....... It might be worth checking the gear ratios calculated elsewhere in this forum to see how wide the power band needs to be. 10,500 - 12,000 for example requires a maximum ratio spacing of 12,000/10,500 = 120/105 = 1.14 so a maximum spacing of 14% between gears to stay within that band.

the 'one-time' adjustment window has passed, (except Honda ?) we have the same 8 overall (through) ratios 'for all races for ever'
(the Cosworth study didn't know this ?)
for most purposes effectively a 6 speed 'box
so we might expect the ratio spacing to be more like 17 or 18% ie 10500 - 12300/12400 rpm ?
(so why wouldn't the gu-h power vary with rpm ? I say)

attempts to have some closer ratios mean that others must be wider
this might be related to some of the so-called 'lift and coast' behaviour

[Andres125sx]

This lack of generation from the brakes is part of the reason teh cars "lift and coast" at some circuits - so they can extend the time the MGUK is harvesting during braking.

Can you explain this please?

I can´t imagine how any mgu-k generation may compensate lift and coast. If they do it because they need to save fuel so then use it to generate more energy, then ok, but using lift and coast only to harvest more energy from mgu-k shouldn´t be worth the time lost, should it?

[drunkf1fan]

This lack of generation from the brakes is part of the reason teh cars "lift and coast" at some circuits - so they can extend the time the MGUK is harvesting during braking.

Can you explain this please?

I can´t imagine how any mgu-k generation may compensate lift and coast. If they do it because they need to save fuel so then use it to generate more energy, then ok, but using lift and coast only to harvest more energy from mgu-k shouldn´t be worth the time lost, should it?

Even then you don't want to harvest from mgu-k. The idea of lift and coast is right there in the third word, coast, not slow. mgu-k harvesting is in effect braking. It's counter productive to lift and coast. THe idea is to save fuel with as little time penalty as possible. You take foot off the throttle earlier to save a little fuel, if you brake earlier as well it would be terrible. If anything with lift and coast you slow earlier but naturally through normal inefficiency forces and actually brake later and less hard when you finally brake.

Lift and coast probably reduces overall harvesting in reality.

[Cold Fussion]

It's only 120 kW of braking power, roughly around 1/10th the full braking effect.

[Arterius]

Can't have one without the other, a larger compressor produces more exhaust gases, which requires a bigger turbine which produces more MGU-H power which makes more MGU-K power which produces more crankshaft power.

Seriously? A normal turbo engine without a MGU-H the turbine would be sized to efficiently produce the required power for the compressor to produce the required boost for the fuel flow. The rest of the exhaust is sent through the waste gate. To efficiently harvest energy for the MGU-H you will require a bigger turbine to make use of all the exhaust gases. This doesn't effect the compressor in any way at all as the fuel flow is fixed and so the boost required for it. As such to extract more energy for the MGU-H you require a large turbine Not a larger compressor.
Therefore Ferrari's problem last year of not being able to get enough energy from the MGU-H come down to having a too small turbine and has nothing to do with the size of the compressor.

[wuzak]

This lack of generation from the brakes is part of the reason teh cars "lift and coast" at some circuits - so they can extend the time the MGUK is harvesting during braking.

Can you explain this please?

I can´t imagine how any mgu-k generation may compensate lift and coast. If they do it because they need to save fuel so then use it to generate more energy, then ok, but using lift and coast only to harvest more energy from mgu-k shouldn´t be worth the time lost, should it?

Even then you don't want to harvest from mgu-k. The idea of lift and coast is right there in the third word, coast, not slow. mgu-k harvesting is in effect braking. It's counter productive to lift and coast. THe idea is to save fuel with as little time penalty as possible. You take foot off the throttle earlier to save a little fuel, if you brake earlier as well it would be terrible. If anything with lift and coast you slow earlier but naturally through normal inefficiency forces and actually brake later and less hard when you finally brake.

Lift and coast probably reduces overall harvesting in reality.

When the drivers lift off the throttle early the car is going to slow down because of drag. In some circumstances (when at high speed), lifting off the throttle would give as much as 1g deceleration. I can't imagine harvesting would make that much of a difference in that braking phase.

In any case, the equation is simple - how much time is lost generating with the MGUK in a lift and coast scenario compared to how much is gained by having a fully charged energy store (or charging it to the allowed 2MJ from brake recovery) ?

Even if they don't use the MGUK in this phase, the equation is the loss of time from getting off the throttle early compared with being able to use a higher power mode on acceleration.

The answer seems to be that there is more to be gained in acceleration than can ever be lost in the lift and coast phase. It seems obvious when you think that any gain in acceleration is maintained along the length of the next straight.

[godlameroso]

Can't have one without the other, a larger compressor produces more exhaust gases, which requires a bigger turbine which produces more MGU-H power which makes more MGU-K power which produces more crankshaft power.

Seriously? A normal turbo engine without a MGU-H the turbine would be sized to efficiently produce the required power for the compressor to produce the required boost for the fuel flow. The rest of the exhaust is sent through the waste gate. To efficiently harvest energy for the MGU-H you will require a bigger turbine to make use of all the exhaust gases. This doesn't effect the compressor in any way at all as the fuel flow is fixed and so the boost required for it. As such to extract more energy for the MGU-H you require a large turbine Not a larger compressor.
Therefore Ferrari's problem last year of not being able to get enough energy from the MGU-H come down to having a too small turbine and has nothing to do with the size of the compressor.

How do you know how much boost pressure teams run exactly? It may very well be that to get the maximum amount of power from these units is to not focus as much on the ICE as on the ERS side. Or being able to make good ICE power even when compromised when making MGU-H/K power. You invest in researching that which is unlimited if you want to make quick gains. Once you find your bearings, the parts that are not regulated can bear the most fruit.

[bergie88]

Can't have one without the other, a larger compressor produces more exhaust gases, which requires a bigger turbine which produces more MGU-H power which makes more MGU-K power which produces more crankshaft power.

Seriously? A normal turbo engine without a MGU-H the turbine would be sized to efficiently produce the required power for the compressor to produce the required boost for the fuel flow. The rest of the exhaust is sent through the waste gate. To efficiently harvest energy for the MGU-H you will require a bigger turbine to make use of all the exhaust gases. This doesn't effect the compressor in any way at all as the fuel flow is fixed and so the boost required for it. As such to extract more energy for the MGU-H you require a large turbine Not a larger compressor.
Therefore Ferrari's problem last year of not being able to get enough energy from the MGU-H come down to having a too small turbine and has nothing to do with the size of the compressor.

How do you know how much boost pressure teams run exactly? It may very well be that to get the maximum amount of power from these units is to not focus as much on the ICE as on the ERS side. Or being able to make good ICE power even when compromised when making MGU-H/K power. You invest in researching that which is unlimited if you want to make quick gains. Once you find your bearings, the parts that are not regulated can bear the most fruit.

You are right, but you are constantly talking about the size of the compressor, which is, in my opinion and I think also the one from Arterius, less important than the turbine size. The compressor should only be matched such that the desired boost pressure is delivered, which is fairly well known under the teams I assume due to the fuel flow limit, also last year. However, the turbine should be sized to extract as much energy as possible from the exhaust gases, which was underestimated for example by Ferrari last year and I think Honda this year.

[godlameroso]

Seriously? A normal turbo engine without a MGU-H the turbine would be sized to efficiently produce the required power for the compressor to produce the required boost for the fuel flow. The rest of the exhaust is sent through the waste gate. To efficiently harvest energy for the MGU-H you will require a bigger turbine to make use of all the exhaust gases. This doesn't effect the compressor in any way at all as the fuel flow is fixed and so the boost required for it. As such to extract more energy for the MGU-H you require a large turbine Not a larger compressor.
Therefore Ferrari's problem last year of not being able to get enough energy from the MGU-H come down to having a too small turbine and has nothing to do with the size of the compressor.

You could have ultra lean running if you design your combustion chambers, and DI system to have a type of stratified charge, so you can burn at or a little bit above stochiometric in part of the chamber, as long as you can control and precisely burn fuel at the right amount, and introduce boost pressure without making the overall AF mixture too lean, I don't see the downside to running as much boost pressure as possible given the PU configuration.

[Andres125sx]

When the drivers lift off the throttle early the car is going to slow down because of drag. In some circumstances (when at high speed), lifting off the throttle would give as much as 1g deceleration. I can't imagine harvesting would make that much of a difference in that braking phase.

In any case, the equation is simple - how much time is lost generating with the MGUK in a lift and coast scenario compared to how much is gained by having a fully charged energy store (or charging it to the allowed 2MJ from brake recovery) ?

Even if they don't use the MGUK in this phase, the equation is the loss of time from getting off the throttle early compared with being able to use a higher power mode on acceleration.

The answer seems to be that there is more to be gained in acceleration than can ever be lost in the lift and coast phase. It seems obvious when you think that any gain in acceleration is maintained along the length of the next straight.

Not sure at all. If true, all teams would lift and coast on every single braking point, except when ES is full, so for example McHonda would do this constantly. But not the case

[Cold Fussion]

When the drivers lift off the throttle early the car is going to slow down because of drag. In some circumstances (when at high speed), lifting off the throttle would give as much as 1g deceleration. I can't imagine harvesting would make that much of a difference in that braking phase.

In any case, the equation is simple - how much time is lost generating with the MGUK in a lift and coast scenario compared to how much is gained by having a fully charged energy store (or charging it to the allowed 2MJ from brake recovery) ?

Even if they don't use the MGUK in this phase, the equation is the loss of time from getting off the throttle early compared with being able to use a higher power mode on acceleration.

The answer seems to be that there is more to be gained in acceleration than can ever be lost in the lift and coast phase. It seems obvious when you think that any gain in acceleration is maintained along the length of the next straight.

Not sure at all. If true, all teams would lift and coast on every single braking point, except when ES is full, so for example McHonda would do this constantly. But not the case

No the comparison is whether or not lifting and coasting for fuel saving is more time efficient then lifting and coasting with mug-k harvesting. Obviously lifting and coasting, even with mgu-k harvesting is a much more time inefficient way then jumping on the brakes (because the mgu-k harvesting is roughly 1/10th the normal braking power).