I really like your research and development here, yet there are a few ideas which I have about the opposed free piston motor design that I would like to ask about. First, it seems like there is a possibility of using the back EMF of the coil to add power to the compression stroke, particularly with a capacitor sized to do so. Second, there seems to be a need for an electrical fan supercharger to maximize volumetric efficiency. Third, I think this could be a hydrogen machine, particularly synthetic hydrogen made from multi-fuel reformation in a GEET fuel processing plasma reactor. In that case the control parameters would be much more narrow and there would be less need for variable compression. And that relates to the question of whether this type of machine can be engineered to run without an ECM, on a straight electro-mechanical basis, which would make it better for military applications where EM pulse weapons would destroy microcircuitry but not larger electrical devices. With hydrogen or synthetic hydrogen as the fuel, the combustion temperatures could be fairly low, which suggests an air cooled design where the electric fan driven suoercharger doubles as the cooling fan, scavenging heat off the cylinders and preheating the charge to optimal temperature. Furthermore, this electric fan could be turning something like a conventional turbocharger as the air handler, which would both place a vacuum on the exhaust and pressurize the intake, increasing the efficiency of the scavenging and reclaiming heat and power from the waste. In very cold climates this would be even more of an advantage, as hydrogen engines run chronically cold. For hot environments it would only be necessary to design the heat exhange surfaces to be large enough to allow adequate cooling with hotter air, and maybe a thermostatic waste gate that dumps the excess exhaust heat.
Also, did you investigate the Stelzer variation of the horizontally-opposed, free-piston engine which eliminate all phasing/variability issues? If so, why did you reject this configuration?
There are already lots of technical risks piled up, in addition to the technical risks of the opposed piston architecture. Remember, Achetes is "solving" the oil consumption problem by not lubricating the compression rings. That can take you so far.
That was very interesting, its nice to see some actual technical info instead of just advertising! Why are you even trying to adapt a off-the-shelf ECU? Wouldnt it be much better to design you own, new ECU for this type of engine since its soo radically different?
Hi Christian - It depends on the application and calibration objective, but for FPEs designed for power density, third party estimates are in the region of >3kW/litre and >0.8kW/kg. See: doi.org/10.1016/j.ecmx.2020.100030 Smallbone et al, 2020, The impact of disruptive powertrain technologies on energy consumption and carbon dioxide emissions from heavy-duty vehicles
Hi Giri - Great question; Good thermal design is key, and in the development system shown the internal combustion system is are partitioned on a separate cooling loop from the e-machines to ensure the operating temperatures for the magnets and the coils remain within their limits.
It is possible to make a 4-stroke Linear Generator with additional bounce chambers to drive the induction and exhaust strokes, but in general the power density, simplicity, efficiency and ultra-low emissions potential of the oil-free, DI uniflow scavenged two stroke arrangement make this a preferred format.
Yes - We make a technology 'platform' comprising linear electrical machines, embedded controls, software and tools. We work with companies including established OEMs and innovative new businesses to help them create new free piston products using this platform together with their own proprietary technology. See www.libertine.co.uk for more details, and please get in touch if you'd like us to help you make such a product!
@Libertine - Linear Power Systems Thank you very much. I'm certainly work on a studying simulation project about space propulsion DV efficiency, i found that internal combustion engine has very impressive efficiency and high Isp which no other types of current space propulsion system can over comes due to their low Isp nature, and in combustion field, free piston is actually the most efficient way im my current comparison in many types engine. So I'm very concerning about you and many combustion engines makers are truly standing on the edge of space technology, and seems no one want to moves on this absolutely step, I wish somehow one day I can work with company especially in this hard time, and before the electric motor platforms overhead ground transport field, combustion needs to move to space.
@@libertine-linearpowersyste8203 Toyota might not want but needs a better hybrid engine like yours. I test drove a Yaris hybrid, and I drove me nuts. ... too much noise and vibration. I literally sounded like a generator. To add to the annoyance, it randomly starts and stops. Imagine an air compressor stopping and starting under your bonnet. I think that you are underestimating the benefits and application of your engine. With such an engine, EV's could use a significantly smaller battery. Say - 100km range. A smaller battery could be swappable and serviceable like the Prius battery. To me, I seem pointless to install an oversized battery to account for battery degradation in 10 years time and range anxiety (like Tesla is doing). Keeping in mind, because battery tech is advancing rapidly, it might be more beneficial to replace an EV battery in 10 years time and recycle the old one instead of lugging dead weight around. On a side note, why don't you guys first design the motor to operate on conventional fuel at one speed, and sell that design tomorrow. If it can't bench test that to work well, it's probably not good enough or refined enough. We need an EV, or EV hybrid, for the masses and not just for the wealthy. On another side note, I've been looked at wheel hub motors to retrofit my ICE vehicle. The company that I was interested in hasn't replied to my email - probably because they have been brought out. But, this is an example of the future whereby electric architecture allows more flexibility. If you want to install strobe lights to track down aliens - done. If you want to install cement mixer - done. If you want to retrofit an old junk car to EV - done. Think Japanese electric cars, and then think about Japanese accessories ... Great work, and I will be looking out for future developments.
@@John____Smith amazing I suggest that you can make the burning chamber smaller, I mean multiple small cylinder instead big one, because it needs efficiency from more quick and less pressure difference compare to big chamber.
There is no need to use electronics that increase the complexity a lot and are fragile. You can know the location of the pistons in simpler ways. Also, generating electricity is not the only purpose of engines.
I gather you are supplying scavenge-air by means of external blower. Why? Surely a stepped-piston configuration would allow you to eliminate this efficiency-robbing extra complication? Did you explore this and if so, why didn't you proceed with it? Secondly; the linear alternator. There are all sorts of configurations and forms these may take. What options best suit a free-piston engine? The Rootes H.O. and indeed, the likes of the NAPIER Deltic represent a good bench-mark for port-design and optimal combustion. You should also consider (so-called) 'reverse-flow' cooling, e.g. Corvette LT1 engine. Also, investigate CATERPILLAR's extensive research into ceramic (adiabatic) engines.
Hi Andre - Thanks for this comment, all very relevant questions. Briefly; 1) Why the external blower? In our IGN20 development engine (shown) we use an external blower to provide the developer (in this case MAHLE Powertrain) with the means to sweep across a range of boost pressures to evaluate scavenging performance and port design. Similarly, the developer can apply a range of exhaust back pressures to evaluate turbo architectures. Separately in other machines we have also built Stelzer-type stepped pistons to evaluate integrated charge compression for compactness and efficiency. For production engines it's possible that developers could choose to go down any of these routes. The purpose of the intelliGEN development platform is to help developers inform that choice through simulation and empirical data. 2) Linear alternator e-machine type? We have built a wide range of e-machine types for different applications. The IGN20 machine is a 'slotless' machine for operational flexibility, but we have also built 'slotted stator' type machines for efficiency and it's likely that production machines will use one of several such slotted architectures. 3) Combustion architecture? The IGN20 machine embodies an opposed piston uniflow scavenged 2-stroke architecture, much like the historic opposed piston engine examples you mention, as well as more recent (and much cleaner and more efficient) opposed piston machines being developed by companies such as Achates and Mainspring. Whilst we provide a 'reference' opposed piston combustion architecture, it's up to FPE developers using our e-machine and control platform to optimise combustion system design details to make best use of the real time compression ratio control capability provided by the intelliGEN platform. I hope that's helpful - Please feel free to reach out via LinkedIn or our website for more details.
yes, but how much electricity? you get into things like current density per square centimeter, magnetic flux density... the core design. theres an issue with linear generators, and its to do with the flux linkage, the coupling, and the stroke. air gaps. as theres only so much stroke you can only have so much pole area and therefore only so much magnetic flux, and then you can only wrap so much copper around it. just because a magnet passing a wire makes an EMF doesnt mean its simple.
@@libertine-linearpowersyste8203 Hi, I tried to add a link to my similar solution '2012 07 26 linear combustion engine 11', maybe YT is blocking adding links.
woow what a great video, I am sharing it. Great work guys!
th-cam.com/video/orgtRCLOTFM/w-d-xo.html
Greating from mr.stelzer ...
Thanks for sharing, very cool.
I really like your research and development here, yet there are a few ideas which I have about the opposed free piston motor design that I would like to ask about. First, it seems like there is a possibility of using the back EMF of the coil to add power to the compression stroke, particularly with a capacitor sized to do so. Second, there seems to be a need for an electrical fan supercharger to maximize volumetric efficiency. Third, I think this could be a hydrogen machine, particularly synthetic hydrogen made from multi-fuel reformation in a GEET fuel processing plasma reactor. In that case the control parameters would be much more narrow and there would be less need for variable compression. And that relates to the question of whether this type of machine can be engineered to run without an ECM, on a straight electro-mechanical basis, which would make it better for military applications where EM pulse weapons would destroy microcircuitry but not larger electrical devices.
With hydrogen or synthetic hydrogen as the fuel, the combustion temperatures could be fairly low, which suggests an air cooled design where the electric fan driven suoercharger doubles as the cooling fan, scavenging heat off the cylinders and preheating the charge to optimal temperature. Furthermore, this electric fan could be turning something like a conventional turbocharger as the air handler, which would both place a vacuum on the exhaust and pressurize the intake, increasing the efficiency of the scavenging and reclaiming heat and power from the waste. In very cold climates this would be even more of an advantage, as hydrogen engines run chronically cold. For hot environments it would only be necessary to design the heat exhange surfaces to be large enough to allow adequate cooling with hotter air, and maybe a thermostatic waste gate that dumps the excess exhaust heat.
This looks promising for systems that need electric power directly. Cost effectiveness is a whole other issue, but keep up the good work
Awesomely!!!
Merrit Catalytic combustion engine (few pumping losses).
U-boats used free-piston engines for compressed air supply.
What is the lubrication doing. the piston rings create friction and what happens at the end of the firing stroke.
Also, did you investigate the Stelzer variation of the horizontally-opposed, free-piston engine which eliminate all phasing/variability issues? If so, why did you reject this configuration?
There are already lots of technical risks piled up, in addition to the technical risks of the opposed piston architecture. Remember, Achetes is "solving" the oil consumption problem by not lubricating the compression rings. That can take you so far.
i was trying to find out how they oiled the sealed, andyeah its silly
Interesting
How do you reduce vibrations in an engine❓️❓️❓️🤔
That was very interesting, its nice to see some actual technical info instead of just advertising!
Why are you even trying to adapt a off-the-shelf ECU? Wouldnt it be much better to design you own, new ECU for this type of engine since its soo radically different?
What kind of power density and specific power would you get out of one of these?
Hi Christian - It depends on the application and calibration objective, but for FPEs designed for power density, third party estimates are in the region of >3kW/litre and >0.8kW/kg.
See: doi.org/10.1016/j.ecmx.2020.100030
Smallbone et al, 2020, The impact of disruptive powertrain technologies on energy consumption and carbon dioxide emissions from heavy-duty vehicles
Is the heat produced in the combustion would reach the permanent magnet and demagnetised?
Hi Giri - Great question; Good thermal design is key, and in the development system shown the internal combustion system is are partitioned on a separate cooling loop from the e-machines to ensure the operating temperatures for the magnets and the coils remain within their limits.
You never really show where the POWER TAKE-OFF is on this engine. What moves? What is driven? How is power generated?
Making it less polluting than a 2-stroke engine is a very low bar. Lower emissions than current 4-stroke engines is a very high bar.
So is it possible to make it a 4-stroke engine?
It is possible to make a 4-stroke Linear Generator with additional bounce chambers to drive the induction and exhaust strokes, but in general the power density, simplicity, efficiency and ultra-low emissions potential of the oil-free, DI uniflow scavenged two stroke arrangement make this a preferred format.
Can the company makes custom special design engine?
Yes - We make a technology 'platform' comprising linear electrical machines, embedded controls, software and tools. We work with companies including established OEMs and innovative new businesses to help them create new free piston products using this platform together with their own proprietary technology. See www.libertine.co.uk for more details, and please get in touch if you'd like us to help you make such a product!
@Libertine - Linear Power Systems Thank you very much.
I'm certainly work on a studying simulation project about space propulsion DV efficiency, i found that internal combustion engine has very impressive efficiency and high Isp which no other types of current space propulsion system can over comes due to their low Isp nature, and in combustion field, free piston is actually the most efficient way im my current comparison in many types engine.
So I'm very concerning about you and many combustion engines makers are truly standing on the edge of space technology, and seems no one want to moves on this absolutely step, I wish somehow one day I can work with company especially in this hard time, and before the electric motor platforms overhead ground transport field, combustion needs to move to space.
@@libertine-linearpowersyste8203 Toyota might not want but needs a better hybrid engine like yours. I test drove a Yaris hybrid, and I drove me nuts. ... too much noise and vibration. I literally sounded like a generator. To add to the annoyance, it randomly starts and stops.
Imagine an air compressor stopping and starting under your bonnet.
I think that you are underestimating the benefits and application of your engine. With such an engine, EV's could use a significantly smaller battery. Say - 100km range. A smaller battery could be swappable and serviceable like the Prius battery.
To me, I seem pointless to install an oversized battery to account for battery degradation in 10 years time and range anxiety (like Tesla is doing). Keeping in mind, because battery tech is advancing rapidly, it might be more beneficial to replace an EV battery in 10 years time and recycle the old one instead of lugging dead weight around.
On a side note, why don't you guys first design the motor to operate on conventional fuel at one speed, and sell that design tomorrow. If it can't bench test that to work well, it's probably not good enough or refined enough.
We need an EV, or EV hybrid, for the masses and not just for the wealthy.
On another side note, I've been looked at wheel hub motors to retrofit my ICE vehicle. The company that I was interested in hasn't replied to my email - probably because they have been brought out. But, this is an example of the future whereby electric architecture allows more flexibility. If you want to install strobe lights to track down aliens - done. If you want to install cement mixer - done. If you want to retrofit an old junk car to EV - done. Think Japanese electric cars, and then think about Japanese accessories ...
Great work, and I will be looking out for future developments.
@@ligmaanl th-cam.com/video/orgtRCLOTFM/w-d-xo.html
@@John____Smith amazing I suggest that you can make the burning chamber smaller, I mean multiple small cylinder instead big one, because it needs efficiency from more quick and less pressure difference compare to big chamber.
There is no need to use electronics that increase the complexity a lot and are fragile. You can know the location of the pistons in simpler ways.
Also, generating electricity is not the only purpose of engines.
I gather you are supplying scavenge-air by means of external blower. Why? Surely a stepped-piston configuration would allow you to eliminate this efficiency-robbing extra complication? Did you explore this and if so, why didn't you proceed with it? Secondly; the linear alternator. There are all sorts of configurations and forms these may take. What options best suit a free-piston engine? The Rootes H.O. and indeed, the likes of the NAPIER Deltic represent a good bench-mark for port-design and optimal combustion. You should also consider (so-called) 'reverse-flow' cooling, e.g. Corvette LT1 engine. Also, investigate CATERPILLAR's extensive research into ceramic (adiabatic) engines.
Hi Andre - Thanks for this comment, all very relevant questions. Briefly;
1) Why the external blower? In our IGN20 development engine (shown) we use an external blower to provide the developer (in this case MAHLE Powertrain) with the means to sweep across a range of boost pressures to evaluate scavenging performance and port design. Similarly, the developer can apply a range of exhaust back pressures to evaluate turbo architectures. Separately in other machines we have also built Stelzer-type stepped pistons to evaluate integrated charge compression for compactness and efficiency. For production engines it's possible that developers could choose to go down any of these routes. The purpose of the intelliGEN development platform is to help developers inform that choice through simulation and empirical data.
2) Linear alternator e-machine type? We have built a wide range of e-machine types for different applications. The IGN20 machine is a 'slotless' machine for operational flexibility, but we have also built 'slotted stator' type machines for efficiency and it's likely that production machines will use one of several such slotted architectures.
3) Combustion architecture? The IGN20 machine embodies an opposed piston uniflow scavenged 2-stroke architecture, much like the historic opposed piston engine examples you mention, as well as more recent (and much cleaner and more efficient) opposed piston machines being developed by companies such as Achates and Mainspring. Whilst we provide a 'reference' opposed piston combustion architecture, it's up to FPE developers using our e-machine and control platform to optimise combustion system design details to make best use of the real time compression ratio control capability provided by the intelliGEN platform.
I hope that's helpful - Please feel free to reach out via LinkedIn or our website for more details.
If magnets are used inside the pistons and the cylinder is covered by copper coils, then the coils will produce electricity.
yes, but how much electricity?
you get into things like current density per square centimeter, magnetic flux density... the core design.
theres an issue with linear generators, and its to do with the flux linkage, the coupling, and the stroke. air gaps. as theres only so much stroke you can only have so much pole area and therefore only so much magnetic flux, and then you can only wrap so much copper around it.
just because a magnet passing a wire makes an EMF doesnt mean its simple.
@@paradiselost9946 Yeah, I see.
why are you deleting my comments?
I've not deleted any comments - could you try to repost?
@@libertine-linearpowersyste8203 Hi, I tried to add a link to my similar solution '2012 07 26 linear combustion engine 11', maybe YT is blocking adding links.
Interesting