1420 replies to this topic

[study]

Guys I have an Question, isnt Renault leading manufacture when it comes to turbos in the car industry? Thanks in Advance

 

Just my own opinion, I'd put BMW above them.

 

A lot of manufacturers have being using turbos for a while

 

ford/cosworth

volvo

saab

mitsubishi

subaru

lancia

[KingTiger]

Thanks TC3000/Lazy, that really cleared it up. 

 

I thought that the MGUH literally harvested heat from the turbo and its systems but in hindsight that doesn't make a whole lot of sense. 

Edited by KingTiger, 20 March 2014 - 03:45.

[DanardiF1]

Just my own opinion, I'd put BMW above them.

 

A lot of manufacturers have being using turbos for a while

 

ford/cosworth

volvo

saab

mitsubishi

subaru

lancia

 

Audi

[TractionEvent]

As an indication, you can look at this illustration:

 

 

the appendix H (Heat), is perhaps a bit of an misnomer.

the MGU-H harvests the energy of the exhaust gas flow, which is mainly pressure/velocity, but it is the heat of the combustion process, that causes the pressure (first inside the cylinder) and then when the exhaust valve opens, the gas exits the engine. The Exhaust flow has velocity and heat, but the turbo and the attached MGU-H making more use of the velocity, not the heat directly (like a Peltier element would do). It's more like a windturbine. The gas velocity, get's slowed down, by the turbine, which causes a slight increase in pressure. This turns the turbine.

On the other side of the turbine (connected via a shaft) you have another turbine, the compressor, which compresses air to feed into the engine.

But, and this is the "trick", because the fuel flow in this engines is limited, you have more energy in the exhaust flow, then you need to drive the compressor.

You can think of it like, having a windturbine on the top of your roof, which rotates in the wind, you use this rotation to pump water for your house.

What would happen if you have strong wind? You would pump more water, but at one point you don't need more water, so what now.

If you don't do anything, you will flood your house, because you keep pumping more water then  you need. So you need to slow down the turbine, by "giving it more work to do".

So, every time you have too much wind, you connect, a generator on top of your watermill to the windmill. The extra load, makes sure, that you don't get more water then you need, but you make use of the extra energy which is there to be harvested from the wind.

In a nutshell, that's what the MGU-H does. Every time, when there is more energy in the exhaust flow, then you need to drive the compressor, it provides an additional load to keep the compressor speed ( and thereby the boost pressure) in check, and produces electricity instead.

The electricity which get's produces, can either be fed into the ES (battery) for later use, or it can be directly transfered to the MGU-K and help to propel the car forward.

The car is then driven to some part by the "engine" (ICE) and to another part via the MGU-K (electrical motor), which is then called hybrid drive.

Too bad that system wouldn't work 

[TractionEvent]

It would if the compressor was faced the correct way though...

[OO7]

The following post came via Timstr11 on the Mercedes W05 Thread:

 

 

A quote from Aldo Costa on Mercedes PU relative to Renault's

 

1. Petr Hlawiczka ‏@hlawiczka  57m

   #F1 Costa: "We have GPS data, so I think everyone can see that, when it’s running at full power, #Renault engine has remarkable performance"

   Expand

    

2. Petr Hlawiczka ‏@hlawiczka  59m

   #F1 Costa: @MercedesAMGF1 won't dominate, see #RedBull progress. @RenaultSportF1 engine has remarkable performance.http://f1news.autoroad.cz/novinky/47102-mercedes-si-nemysli-ze-letos-bude-dominovat-upozornuje-na-vykonny-motor-renaultu/ …

[FirstWatt]

Too bad that system wouldn't work 

Why??

 

The drawing is perfectly OK as a simplified setup.

 

TC3000 calls the direct use of the electrical energy, generated in MGU-H and directly used in MGU-K, "hybrid drive".

 

I'll rather call it compounding, which has been exploited eg by Wright for aviation engines, by Scania and Volvo for trucks, or in marine engines: Here

Cosworth calls this mode "self sustained mode" because it doesn't need to accumulate or use energy from a storage.

[Lazy]

The following post came via Timstr11 on the Mercedes W05 Thread:

Is that with 4% higher fuel rate

[OO7]

Is that with 4% higher fuel rate

 Do you know what Lazy, a few minutes after I posted the message I began to think the same thing.

 

To be fair I would think data from other Renault powered cars was included.

[FirstWatt]

I don't think he is questioning the general principle behind such a setup, just pointing out, that in the graphic the compressor wheel is shown incorrectly.

If you take the turbine side, and see in which direction the turbo would spin, then the compressor wheel would turn in the wrong direction, for it to work.

If you look closely (pay attention the "pitch" of the compressor blades), I'm sure you will see what he is getting at.

Aha thanks, didn't spot this...

[oetzi]

I was looking for the table that shows the year-on-year increase in permitted ERS usage for the new PUs - I know I've seen it, but Google is not my friend on this. Does anyone know where to find a copy?

[FatHippo]

If such a list exists, it could be found in the Technical Regulations - available at a FIA website near you.

[oetzi]

Thanks but no, checked there. For future years they only have tables of what's getting frozen and weighting of parts.

 

Anyone else have any ideas?

[FirstWatt]

So much for the valuable information at this site (TJ13):
 

After the Australian GP rumours begun to circulate about what could have been the secret of so much performance and reliability on the Mercedes power unit.

Reliable sources have indicated that the simplified design of the power unit may hold the advantage to the Mercedes PU106. According to these rumours, Mercedes have chosen to give up some of the power of the ERS to have more reliability and a continuous and constant flow of energy. What is it about?

Well, at Brixworth, engineers chose to renounce a part of the energy by reducing battery pack storage capacity (2MJ instead of 4MJ) , the advantages of this would be many. First of all – a much lighter battery pack- around 12/13Kg instead of the 25Kg the competition are running with. The reduced amount of energy translates also into lower cooling needs and in a more clearly defined package.

Now let's look at the regulation:
 

5.4.3 The total weight of the part of the ES that stores energy, i.e. the cells (including any clamping plates) and electrical connections between cells, must be no less than 20kg and must not exceed 25kg.

Indeed questionable, how much c..p is spread by sites which seem to be serious.

[Gorma]

So much for the valuable information at this site (TJ13):
 

Now let's look at the regulation:
 

Indeed questionable, how much c..p is spread by sites which seem to be serious.

Well they can have smaller batteries with reduced cooling needs and ballast within the batterypacks. 

[Clatter]

Well they can have smaller batteries with reduced cooling needs and ballast within the batterypacks. 

I'm not sure that packing ballast around the batteries is going to aid cooling though.

[Gorma]

I'm not sure that packing ballast around the batteries is going to aid cooling though.

Well not around them, below them. You can have a 13kg battery pack on top of 7kg of ballast rather than a 25kg battery pack. I'd assume that the cooling need for a 13kg battery is less than for a 25kg one. 

[rodlamas]

Question: can you still deploy 4MJ on a qualifying lap just having 2MJ in store + having been able only to harvest 2MJ per lap?

[FirstWatt]

I'm not sure that packing ballast around the batteries is going to aid cooling though.

Not really, as cooling demand is not given by the amount of storage (max 4MJ or 1.11 kWh) but from the technology used (inner resistance) and rate of charge / discharge.
 
And you cannot deliberately add ballast, as it is required that the total weight of the part of the ES that stores energy, i.e. the cells including any clamping plates and electrical connections between cells have to be 20-25kg, not the housing etc.

One possible way which Mercedes could have chosen is the use of Supercaps or Ultracaps (FastCap being a brand eg) which have poor energy density but high power density.
126 kW charge / discharge power and a capacity of 1.11 kWh gives >110C, you already are at the limit of most cells according to the Ragone Chart here.

Using capacitors may reduce capacity but increase available discharge power.

But it will not save weight in any case, and will be at the cost of increased dimensions....

[Wuzak]

Question: can you still deploy 4MJ on a qualifying lap just having 2MJ in store + having been able only to harvest 2MJ per lap?

 

Yes. Providing you use some of the storage before you recover energy at the next corner.

 

I guess the advantag of having 4MJ of storage is that you can run a qualifying lap without needing to harvest from the rear brakes, which should, perhaps, give a more stable braking platform.

[Gorma]

It seems that the Renault and Ferrari power units are more thirsty than Mercedes. Williams for example didn't even start with the maximum allowed fuel, which to me is quite amazing.