TERS : Thermal Energy Recovery System

[wuzak]

planned development of the V16 BRM was boost/ rpm matching by vortex throttling of supercharger entry at high engine rpm

The BRM V16 supercharger was developed by Rolls-Royce. It was a mini-Merlin supercharger. Two stages on a common shaft.

There were some bits that RR recommended but BRM did not use. I think they were intake guide vanes.

[WhiteBlue]

I have re-read the regulations and the turbine has to be connected to the compressor at all times.
So there is no real chance of any power train development. F1 remains a restricted aero formula....

I think you are a bit over the top with your interpretation. I got the impression from the reports of the working group that there will be development steps in the future. But those steps will be under tight control of the F1 commission which is still dominated by the teams. And if the team majority is mostly concerned about a cost race they will handle developments quite restrictive. So a fair assessment in my view would be a very slow development pace compared to the time before the engine freeze. Homologation seems to be there to stay and development only be available in carefully metered drops. I do not like it very much but the cost concerns have to be taken seriously. Unless the FiA comes up with a budget cap that the top teams subscribe to.

[autogyro]

Why not accept that it is the FIA working groups that design F1 cars these days and not the teams.
The teams simply fine tune the add ons when they are allowed.

[Nando]

It depends. For example Ferrari was the one pushing for V6´s so i´m sure it´s not all FIA design when it comes to the cars.

[LogicPro]

I'm going to ask you a question that may sound stupid, but I couldn't find this info on the web...

Is the turbine of the new TERS also connected to a compressor as on normal turbocharged engines? (= it both boosts air pressure into the cylinders and provides additional power as KERS does)
Or is it only linked to the electric system that stores energy into batteries? (with no compressor)

Thank you in advance.

[Tommy Cookers]

Is the turbine of the new TERS also connected to a compressor as on normal turbocharged engines? (= it both boosts air pressure into the cylinders and provides additional power as KERS does)

yes, because the rules demand this
(IMO for simplicity and road relevance)

although seperation of supercharger driving and power recovery turbine functionalities has attractions and historical precedents
eg a few thousand? Wright 'Turbo-Compound' Duplex Cyclone aircraft engines made around 1950-1960

[WhiteBlue]

Is the turbine of the new TERS also connected to a compressor as on normal turbocharged engines? (= it both boosts air pressure into the cylinders and provides additional power as KERS does)
Or is it only linked to the electric system that stores energy into batteries? (with no compressor)

You basically have a conventional turbo design with the turbine on steroids. It is over sized in order to extract all the energy from the exhaust gas that can be extracted. Naturally the compressor alone could not handle all the power and torque of that turbine. To make use of the excess energy not needed to drive the compressor there is a motor/generator unit attached to the turbo shaft which runs at full speed of the turbo. This MGU-H can run in motor mode and spool up the compressor to avoid turbo lag. But mainly we expect the MGU-H to harvest electrical energy which will be directly transferred to the second MGU-K to push the car. The MGU-K is the unit that previously was called KERS. From next year on it will be run in continuous mode all the time when the throttle pedal is pushed. KERS buttons will be abolished. So the combination of the turbine, the MGU-H and the MGU-K will build a hybrid electric turbocompounder.

[LogicPro]

Thanks for both replies.

This MGU-H can run in motor mode and spool up the compressor to avoid turbo lag. But mainly we expect the MGU-H to harvest electrical energy which will be directly transferred to the second MGU-K to push the car.

So a deisgner has to choose if the MGU-H has to boost intake pressure (avoid turbo-lag) or to harvest energy used by the MGU-K, isn't it? Or is the same system designed for both purposes?
I'm thinking that if a team wants it only to harvest energy for the MGU-K, then it can be designed only as a generator and not motor/generator: could it result in a weight reduction?

[Tommy Cookers]

So a deisgner has to choose if the MGU-H has to boost intake pressure (avoid turbo-lag) or to harvest energy used by the MGU-K, isn't it? Or is the same system designed for both purposes?
I'm thinking that if a team wants it only to harvest energy for the MGU-K, then it can be designed only as a generator and not motor/generator: could it result in a weight reduction?

No
in principle (many) electric 'motors' and 'generators' are machines that will work as motors if supplied with electrical energy, and as generators if supplied with mechanical energy
this applies in ordinary cars (it was very visible with the dc generators in old cars)
also if the starter remains engaged when the engine runs it will act as a very powerful generator (then fail)
(some small-engined cars had 1 electrical machine for starting and generating eg 'Dynastart' motor-generator)

the MG is one electrical machine operable (at different times) as a motor or as a generator (it is not 2 machines)
this combined functionality is the reason behind the 2014 rules
it will be simpler or lighter than (otherwise attractive) schemes with seperate supercharger drive and exhaust power recovery

(I think the plan has (European) car makers marketing this to us soon, at a price)

[WhiteBlue]

Agree with TC there. There would be no weight saving, only loss of functionality if one of the functions of the MGU-H was not used.

[autogyro]

Let us hope that in the future the FIA see fit to allow designers to disconnect the mechanical link between the turbine and the compressor.
IMO it is only then that the use of modern electronic control will be able to achieve real fuel savings.

[ringo]

That would have a lower overall efficiency.

[Tommy Cookers]

arguably the 2014 engine is not a true compound because the PRT function is not seperate
wouldn't the turbine people rather it was ?

arguably the (electrical) exhaust power recovery only makes sense because the 'son of KERS' system is mandated
without that, the scheme does not seem better than mechanical compounding

given that the engines run (or only need to run) at a nearly constant speed (and have effectively a constant fuel rate)
mechanically driving the supercharging need would be better

although for road cars, hybrid supercharger drive (mechanical drive in series with a small intermittent modulated MG) is good


does anyone think that the 2014 rules are not related to upcoming marketing/legitimising of complicated road car product ?

[WhiteBlue]

The main concern of the engine working group was cost control. They did not want a development cost race and they started with a simple turbo charger. The heat recovery function was later added as an enhancement. The original plan called for a simple L4 turbo to be introduced in 2013. In 2014 heat recovery was supposed to be introduced in an undisclosed way. When the whole project got delayed by switching the engine to the V6 format they decided to roll the heat recovery into the same initial spec but they still wanted to keep it simple and a standard design. So the current spec is a compromize.

[autogyro]

It is not possible to encourage the development of energy recovery systems for internal combustion engines, if you tightly specify the design layout.
All the powertrain designers can do is fine tune an established sytem.
For what purpose?

The end result in spin off into road vehicle technology will be no more than marketing hype.