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Liviu Giurca, your post is obviously self-promotion since it links to a paper with your name on it. Nevertheless ... Nissan's solution "packages" in the same shape and size as a normal in-line 4-stroke engine except that the crankcase is a smidge wider - but implementing counter-rotating balance shafts (no longer needed) would also require space down there, so it ends up taking the same space as an in-line engine with balance shafts. No changes to vehicle architecture, same transmissions still fit, etc. Your opposed-piston engine is nowhere near the same shape and size as a conventional engine. And ... Nissan's engine will work with conventional emission controls for 4-stroke spark ignition engines (lambda sensor and 3-way catalyst). Yours, being a two stroke, will not. And two-strokes invariably have problems because of the need for the piston rings to be lubricated and to cross the intake and exhaust ports. As for the people wanting to simply ban all combustion engines and thus there is no point to improve the technology that we already have ... you are operating in a dream world. Combustion engines are going to be with us for quite a while and we might as well make the best of them. If Nissan's solution allows a spark-ignition engine to roughly match the efficiency of a diesel engine at part load (and it could) it solves a lot of headaches. I suspect it will be thirsty at full load (in low-compression mode) so this ain't the solution for long-haul trucking, but it'll do for automotive applications (which run at part load most of the time).
I would encourage people to google-search "I-71 bus crash" to understand why school buses today are diesel powered. By no means was switching to diesel the only way to deal with that situation, but it is best not to forget the lessons of the past. The location of the fuel tank with relation to the main entrance/exit door requires consideration. Front-engine school buses to this day still have the fuel tank in the same place.
I don't have a problem with most of the various driver aids being implemented ... but I have a problem with how Tesla is promoting their use. Volvo, M-B, etc who also use systems from the very same suppliers that Tesla uses are correct in their implementation: these systems at their current and near-term-foreseeable level of development should ENcourage the driver to pay attention and DIScourage driving hands-off. Automatic braking systems should not smoothly and comfortably bring the car to a stop if activated, for example. That would encourage drivers to rely on them. They should deliberately harshly engage the brakes in an uncomfortable manner to encourage the driver to not do whatever they did again. The safety function is still accomplished ... and the driver receives motivation to not do that again. Same with automatic lane-keeping; if corrections are made harshly it encourages the driver to stay awake, and if the corrections are a function of whether the driver used their indicators then that encourages the driver to use them. If the systems encourage the driver to pay attention and drive properly then there is no issue with handing over control to the driver in circumstances that the automated system can't handle (evidently, a white transport truck trailer against a sunny sky!), because the driver is already in control. The hand-over to human control is one of the big issues with how Tesla is trying to do it. What should the automation do if it knows it's entering a situation that it can't handle and the human does not take control when requested? Stop in the middle of an active lane where a motorway ends or a construction zone starts or when snow accumulation reaches a level where lane markings are obscured, and allow the vehicle behind to plow into it? (and there are many places in the world where stopping in an active traffic lane is illegal ... and rightly so) The technology is not perfect ... and average untrained humans can not be trusted to use it properly. Human-factors engineering is tough. The aircraft industry has learned many things the hard way already. This follows suit.
I would beg to differ on what the prime factors of the US traffic fatality rates are. Drunk/impaired driving, yes, I agree. Texting or otherwise distracted, that as well. High speed, not so much. Most of Europe has a motorway speed limit of 130 km/h give or take. Ontario (Canada) has the lowest such speed limit (100 km/h), but it's widely ignored. The actual travel speed on motorways is little different. (120 - 130 km/h, or 75 - 80 mph if you wish) And in any case, motorways are the safest roads, city streets the most dangerous. One factor Toronto shares with european large cities is that about half the traffic fatalities are pedestrians (many of whom have their noses buried in their phones nowadays). The USA has a problem with people not wearing seat belts in cars and not wearing helmets on motorcycles. Canada and all of Europe require these. This is a rather large factor.
The Tesla autopilot incidents are under discussion in another engineering forum that I am in. It seems that the system is only capable of operating properly under a fairly narrow set of conditions, and anything outside of those can cause it to fail. It does not do cross traffic, it does not do stop signs and traffic signals, etc. It does not do something that all good human drivers do ... scan their environment for potential threats, predict those threats, and take preventive action against the threat materializing. (It can be as simple as noting that there is a vehicle in an adjacent lane which is ending, predicting that this vehicle will do a lane change, and positioning oneself such that the other vehicle can do this action without conflict. Good drivers do this ... many drivers do not ... Autopilot does not) "Driver aids" - systems that bail drivers out when they screw up - are already here and will develop further. But Sweden and elsewhere don't have any more "self-driving" than the USA does. If there's a difference in safety statistics, this isn't the underlying factor. It cannot be. I can say what some of the differences are ... Better training of drivers, periodic re-testing of drivers, periodic safety inspections of vehicles (and these are inspections that actually have some teeth), better public transit, enforcement of traffic rules other than speeding (plenty of intersections have cameras), better lane discipline, drivers who know how to yield, roadway designs with roundabouts in place of traffic signals or stop signs (much harder to have a head-on or left-turn-into-oncoming-traffic), mandatory seat belts for car drivers, mandatory helmets for motorcyclists, and in some cases, roadways designed with consideration for what happens when a vehicle leaves the roadway.
... and a sun low in the sky is not a foreseeable situation - in fact something that everyone has to deal with every day? ... and their radar / ultrasound systems which ought to be immune to lighting conditions didn't work either? Tesla's autopilot systems have not had sufficient validation testing. Period. Other manufacturers have the same sensing technology available to them but they take greater measures to encourage the driver to remain in control of the vehicle. There's a reason for that. It's not ready for prime time. I know Tesla claims this is the first fatality in however million miles of Autopilot operation. Sure. Autopilot operation is in mostly low-risk scenarios - late model vehicles operated by wealthy-demographic owners (not teenagers) on motorways in good weather, etc. Doesn't work in adverse weather. Doesn't work in intersections (following stop signs or traffic signals). You know, situations where collisions actually occur ... 100 million miles of steady speed motorway driving in good weather is not comparable to 100 million miles of mixture of that plus urban plus construction zones plus rain plus snow and all the other stuff that humans have to deal with.
Henrik, you are optimistic on the timeframe by at least an order of magnitude. The validation testing on such a system alone - the validation testing that Tesla should have done! - will take a few years, and that's assuming you don't run into a show-stopper in the process of doing so. These systems do not work properly in adverse weather conditions or in traffic circumstances that are out of the norm. Tough one: Police officer directing traffic. Tougher one: Civilian directing traffic because the police haven't arrived yet. Tougher yet: Kids up to no good and waving their arms. The crash in Florida happened at an intersection with visibility conditions that could hardly have been better. And it still happened because a circumstance developed that the system could not deal with - one that a human could have easily dealt with, IF that human had been paying attention instead of watching a movie ...
Further evidence that Tesla's system is not ready for prime time and hasn't gone through sufficient validation testing. Lulling people into a false sense of security is extremely dangerous.
There is no way solar and wind are going to replace Bruce, Pickering, and Darlington nuclear plants in Ontario; these are ~50% of Ontario's electrical supply and that supply is not dependent on weather, and if the electric-car proponents (or even more so, fuel cell proponents!) get their wishes, we will be needing more, not less. Wind power is an uphill battle thanks to NIMBY residents. All I've heard about California's electrical supply is that it is strained to the limit as it stands right now. Losing a base-load nuclear plant sure doesn't seem like the right direction to go. The left hand (that wants to shut down nuclear power) does not know what the right hand (that wants more electric cars and fuel-cell vehicles that aren't really-expensive fossil-fuel vehicles) is doing.
As far as I can tell, this operates in the same manner as last year's Accord hybrid. Why would you want to eliminate the engine-connected motor/generator? Without it, there would be no way for the car to start off from a stop and operate at low speeds if the propulsion battery is discharged. The clutch cannot be engaged below engine idling speed (the car has to get moving first) and without a multi-speed gearbox, the mechanical coupling cannot provide enough torque to the wheels for an uphill start. The old Honda IMA system only had one motor/generator, and had a CVT transmission. The VW Jetta hybrid and all of the Hyundai/Kia hybrids only have one motor/generator but they have a multi-speed gearbox. The Toyota and Ford systems have two motor-generators but the design of the planetary coupling results in a maximum road speed above which the combustion engine must start. The BMW i3 is totally series hybrid with two motor/generators (actually, one of them is a generator only in that application) and no mechanical coupling, but that stinks when the propulsion battery is discharged. The new Chevrolet Volt is sorta like that except it has some clutches inside it to overcome that limitation. There's lots of ways to do these and there are good and bad things about every one of them.
There is a failure to explain acronyms here. What is the difference between a "BEV90" and a "BEV210"? What is the difference between a "PHEV10" and a "PHEV35"? One thing is plenty apparent: many of the alternatives are pretty costly and in some cases for rather marginal improvements, and if the end user isn't paying then the taxpayer will be paying, and either way, that's a tough sell!
There's no question that we need better rail infrastructure in this continent. But 300 km/h freight trains - presumably electrically powered?? Any idea how straight and level a rail line needs to be in order to do that without the train flying off curves? How's that going to work in the Sierra Nevada ... or West Virginia? Any idea how much power/energy it takes to accelerate 5000 tons to that sort of speed? Or climb a grade at that speed? Any idea how long such a train would take to accelerate to that speed ... or stop from that speed? No one (with any sense) is asking for this. A better rail infrastructure with ordinary top speeds of 100 - 130 km/h and therefore manageable demands for curves and slopes and rail crossings will do just fine. FWIW one of the big cost- and time-adders of combining rail with short-haul truck at both ends is the need to transfer cargo. You can do it with sea containers, and you can do it with flatbed rail cars that take a whole trailer on board, wheels and all. There are costs and downsides to both methods and some types of cargo can not be dealt with safely in this manner. Juggling rail cars at a rail yard so that containers with different destinations end up on the correct trains is no small chore; it takes up land, it takes up time, and it costs something! Part of the duties of a train crew include inspecting the equipment for safety hazards and checking for safety hazards as the train travels. There's more to it than just controlling the speed of the train and automating this sort of thing requires considerable risk analysis. Don't jump to conclusions.
Saying that electricity costs "20%" that of diesel is way over-optimistic in my area. I've done the electric car versus gasoline car math, and it's more like 50%, and heavy-truck diesels have much higher efficiency than passenger-car gasoline engines which would reduce this difference. Once the government figures out how to tax heavy commercial vehicles independently of their fuel source (which they will eventually have to, since these vehicles are responsible for a large portion of wear and tear on roadways) this could very well wipe out any hypothetical energy cost advantage that may currently exist. This is a difficult application, and I think for the moment that our efforts would be better spent elsewhere. Commuter vehicles, short-haul trucking, buses, local transport and service vehicles are all much better candidates for electrification. The inability to achieve perfection should not stop us from doing the things that we know how to.
You're dreaming if you think the need for long-haul trucking will go away any time soon. I alluded to people in Maine buying oranges. In reality it applies to almost all fresh foods that are not available locally (in either geography or time). I can get locally-grown corn on the cob in July, but not in December. Locally grown citrus fruit or bananas does not exist. Stuff like this is shipped on trucks because the shipment is time sensitive. Getting entire populations to exist only on locally grown food to eliminate long-haul trucking? Good luck with that. The entire northern half of North America has several months of the year with no locally-grown fresh fruits and vegetables. And these are far from the only examples. Everyone buys stuff over the internet these days. How do you think that's getting from (all too frequently) China to your doorstep in a week? Air freight and trucking. Would you prefer the thing you bought over the internet to take two months to arrive instead? Industrial machinery ... equipment to make parts for a much-vaunted electric vehicle that shall remain nameless (I know but cannot say - personal involvement, with non-disclosure agreements in place) was built in one place and shipped by truck to the production site half a continent away. Every time you hand off from one type of transport to another there is a risk of damage being done - and it takes time. Reality, folks. Deal with it.
There's no need for it to be autonomous; drivers can park one truck and jump into the next one ... in theory. Shippers will really love the extra delays that this will build into the system ... not! This does not work for owner/operators, either. Some would argue that the right solution for long-haul trucking is trains. The delays for time-critical shipments already make this hard to do. If people in Maine would stop buying oranges that have to come from somewhere else in the world ... good luck with that! I think we need to do things that we know how to do first. Short-haul trucking is a lot easier to deal with.
Supposing we have a VW e-golf, the new one with 200 km range and 37 kWh capacity, if we refill every 2nd charging station (every 160 km) it will need about 80% of its capacity at that time, i.e. 30 kWh, and at 50 kW charging rate (which is decent, but not great) it will take 36 minutes to recharge after having driven 160 km (so perhaps 80-ish minutes of driving followed by 36 minutes charging). Of course this is assuming you are driving repeatedly in this manner. If you have to go 160 km from home then you start out with your overnight charge and you only have to do this top-up once. Your hypothetical 1000 km trip would require 4 recharges. Keep in mind also that the whole of Germany is about 600 km across ... and is well served by trains and airlines. This infrastructure can (and, evidently, will) be built NOW. The hydrogen infrastructure is still a gleam in someone's imagination, and will be for quite a while ... maybe forever. Someone who wants an EV and really does want to do cross country trips with it would be well served to buy a Tesla rather than an e-Golf given that (A) the Tesla will go further on your initial overnight charge, and (B) the supercharging stations have twice the recharging rate ... It appears that Germany is well served by Supercharger stations that are already built and up and running; SAE Combo has some catching up to do.
The latter poster might not know that Ontario gets about 50% of its electric power from nuclear (and has an excess supply of nuclear power most nights), a good chunk of the rest from hydroelectric, then natural gas, then wind, then solar. No coal.
All well and good ... BUT ... They are missing the most important part of the picture, which is the number one thing holding me back from buying a Chevrolet Bolt as my next car ... publicly accessible SAE Combo compatible Level 3 charging stations in useful locations, because there are currently NONE. It would meet my needs to install such stations at two of the OnRoute service centers between Toronto and Windsor, and perhaps the one in Kingston and the ones near Barrie; obviously in both directions in all cases. Level 2 charging stations don't get the job done. I can't do a Windsor return trip with a 9 hour wait to get recharged in order to get home.
KiwiME, that information is proprietary, but these new transmissions are certainly being designed with a view towards minimizing internal friction. This transmission has 6 internal clutches and only two of them are open (disengaged) at a time - it's the disengaged clutches that have relative velocity between the clutch plates and that's a source of loss; the engaged clutches have no slippage and therefore no loss. In addition this transmission has other features designed to reduce oil-churning and oil-pumping losses (mentioned in the article); it ought to be equal or better than the ZF 8-speed which is already very good. The close ratio spacing allows the torque converter to be locked up a greater percentage of the time, and that's the big source of losses with normal automatics. I would expect this transmission to have pretty comparable (and high) mechanical efficiency to the various DCT or manual transmissions, better than any CVT, and certainly better than old-style automatics (that had ratios too far apart to allow torque converter lockup except in top gear). Disclaimer; one of my customers will be making parts for these, which is how I know a thing or two about them (they are making pre-production parts now). The article doesn't mention it but this is a Ford and GM co-developed transmission with Ford leading on this one (GM is leading an upcoming new front-drive transmission). The initial applications will be in high performance vehicles to showcase its capabilities (Ford Raptor, Camaro ZL1) but this transmission eventually will be coming to F150s and Silverados everywhere, replacing the Ford and GM rear-drive 6-speed transmissions, and that's when the big production volume hits.
For the foreseeable future, it will not be necessary for EVs or any other alternate-fuel vehicle to be all things to all people. There are two four-wheeled contraptions in the driveway at my house. One of them is a daily-driver that sees visits to job sites and groceries and the like. It's currently a subcompact car with a gasoline engine, but a Tesla 3 would do the job (via Supercharger stations that already exist) and a Bolt would do it if someone would get off their butts and build public-access Level 3 SAE Combo quick-charging stations, of which there are none in Ontario. Some days I would need a quick top-off charge - not necessarily a full 30 minute charge - to get home. I can live with that. The other four-wheeled contraption is used almost exclusively for vacations and long trips. It uses twice as many L/100 km but sees only a quarter of the annual mileage of the daily-driver. It would be pointless to make this a hybrid. It very frequently gets to highway speed and has cruise control set for long periods. No point having regenerative braking if you never use them. (Henrik's "self-driving" scenario i.e. rental vehicles would not work ... the interior of this vehicle is customised, there's more to it than just getting from one point to another ... and by the way, "self driving" is an independent function from "rental EV", these need not be tied together) Replacing the daily-driver with an EV and leaving the vacation vehicle as a gasoline engine vehicle would reduce household gasoline contraption by around 60% - 70%. I would apply the seemingly all-too-rare common-sense factor and call it "good enough".
To my knowledge, no reasonable person is asking for a BEV to be able to recharge in only 10 minutes after 400 mi / 600 km range. It's an order of magnitude past the point of diminishing returns. For people with recharging capability at home (and this will increase over time) an overnight charge is good enough, and the Bolt and Tesla have range that is good enough for most people. A 30 minute charge after 200 mi is acceptable to most people and would require somewhere near 100 kW of charge rate for a vehicle like the Bolt or Tesla 3, and that's doable today. Most people will not have to quick-charge in their daily travels, occasionally they will need a top-up (not even a full charge) to get home, and only on long trips would quick-charging be relied upon. This is good enough for most people as long as there are charging stations available. The infrastructure required to implement wide scale hydrogen refilling stations dwarfs that required to make EVs that are good enough for most people (and you'll never get them to be all things to all people all the time). And at the end of the day, if you want either the electricity or the hydrogen to come from a renewable source, the "miles down the road per wind turbine" or the "miles down the road per square kilometer of solar collection" is way, way ahead with BEV than with hydrogen.
I see only one direct injector per cylinder - within the bank of the V between the two intake valves, as usual. Direct-injection engines have had plenty of issues with carbon build-up on the intake valves because there's no fuel wash over the back of the intake valves, and having a port injection system fixes this. It allows the flexibility of using the direct injection system when it's advantageous to do that, and port injection when it's advantageous to do that.
Whether you use one motor driving through a differential or two separate motors each with a separate reduction gearbox shouldn't have any meaningful effect on the efficiency of the powertrain as a whole. Using two separate motors with two sets of inverter outputs will cost more but allows a limited-slip effect which is better for slippery surfaces, that's about all. If you want to connect the motors via multi-speed mechanical transmissions as suggested by someone above (and there are some advantages to doing so) then using two separate such drivetrains starts costing a lot more because now you need two of those, too! In-wheel motors aren't favorable in light-duty vehicles because there is a lot of equipment competing for space at the hubs (particularly with the front wheels) and the unsprung weight has adverse ride and handling effects on rough roads. The Tesla P90D uses one chassis-mounted motor in the front driving through a diff and CV shafts, and two motors in the back driving through CV shafts, and there's good reason for it being done that way. The Chevy Bolt uses one chassis-mounted motor driving the front through a diff and CV shafts, and my money is on the Tesla 3 doing the same (but in the rear) in order to save $ $ $.
The OPOC design will not allow this injector geometry nor will it allow a conventional injector geometry with the injector in the cylinder head pointed straight at the center of the cylinder, because it has no cylinder head (pistons face each other). All it means is that this research was never intended to be applied to an OPOC and to make an inference that it somehow could be, is not valid. This research was meant to be applied to a normal piston layout with a fixed cylinder head and 4 valves per cylinder with all three injectors fitted into real estate in the cylinder head that doesn't contain valves. OPOC requires side mounted injectors and flow patterns within the combustion chamber that are nothing like those of a normal bowl-in-piston with central injector design.
OPOC will not allow that injector and combustion chamber geometry. (Not saying it wouldn't allow some other geometry - it just won't allow that one.) That engine design is a whole new set of issues to deal with. The injectors would no doubt all be fed by the same common rail fuel supply. Pump and pressure regulator stays the same, fuel filter stays the same. It adds more injectors and more wiring to them, that's the added cost. The exhaust aftertreatment is the expensive bit. I have my doubts that this system could improve combustion efficiency by enough to remove the need for DPF and NOx aftertreatment. A system like this would likely have its cost/benefit analysis work out better for a large engine, such as heavy truck applications, as opposed to automotive.