Featured Hyundai IONIQ - Prius competitor?

. Is it how they get 104HP from 1.6L Atkinson engine? This is comparable to Toyota's 1.5L Otto cycle engine. How that emissions are going to impact their European sales?

 

I doubt that Ioniq's high emissions will impact European sales. The car has its approval before the new WLTP test cycle comes in. Its CO2 numbers are good. Also, automakers are being allowed some leeway to exceed emissions limits for the first year or so of the new test cycle. But, for anyone who cares about the environmental impact of their driving, Prius is a better choice. Hyundai and other GDI makers will eventually have to up their emissions performance, perhaps by installing particulate filters.

I consider it disgraceful that new cars are still being brought to market that fail to meet the limits specified in regulations that are several years old. And they are getting away with it. Some non-plug-in cars do properly pass the Euro6 limits in normal driving, including Toyota hybrids and also some BMW and Mercedes diesels. The Suzuki Ignis SHVS mild hybrid also passes and is the least expensive car to do so in ADAC tests.

 

The chemical energy of a fuel is converted to mechanical energy during the expansion, or power, stroke of the piston. All else being equal, the longer that piston travel is, the more fuel energy that gets put to work moving the car. A long expansion ratio means a high compression ratio though. Which generally means a higher octane fuel is needed in a spark ignition engine to avoid knocking.

A higher octane requirement on a car generally hurts sales, because people are generally, well, cheap. Aside from raising the octane minimum of regular gas, which isn't really that bad of an idea, there are other technical options to getting the efficiency benefits of a long expansion stroke. Atkinsonation is one method known here; valve timing delays closure on the compression stroke so that the effective ratio is lower. This reduces the power output of the engine though, which is why it is used in hybrids; the electric motors supplement the ICE power output.

Another method is to use direct injection. Heat is a big cause of knock, and higher compression generates more heat. Instead letting a mix of fuel and air get sucked into the cylinder on the intake stroke, a direct injection engine squirts the fuel in near the end of the compression stroke. The fuel doesn't heat up by being compressed, and it actually cools the cylinder some. This allows lower octane fuels to be used in high compression engines. This improves the engine's power and efficiency without the sales hurdle of needing more expensive fuel.

The downside of DI in the past was carbon build up, but better engine controls have allowed it to go mainstream. The issue now is particulate emissions. It is the same injection system used in diesels, so it has some of the same problems. Car emission regulations basically ignored particulates from gasoline cars, and some port injected ones exceeded the limits that got DPFs on all the diesel cars. The GDI engine going mainstream means that the particulates can no longer be ignored.

There might be improvements and engine designs that reduce the particulates produced in a GDI engine, but an exhaust filter ultimately does a better job. Eventually, we'll see exhaust filters on even port injected cars; a DPF equipped diesel emits less particulates than gasoline cars now.
Attacking GDI engine particulate emissions - SAE International

 

Trollbait - excellent article (as usual)

Question: You said - " Eventually, we'll see exhaust filters on even port injected cars; a DPF equipped diesel emits less particulates than gasoline cars now."

Will exhaust filters cause higher exhaust back pressure?

 

Unless the intake valve is held open during part of the compression stroke moving charge back into the intake manifold. In a four cylinder engine, another cylinder will be in intake stroke so there won't be any pressure issues in the intake manifold.

The only problem is how to vary the duration and angle of the intake valve operation. In a perfect world, no throttle plate would be needed. Just intake air pressure and temperature to quick adjust the fuel injection.

Bob Wilson

 

Yep, I mentioned adjusting the effective compression ratio through the intake valves.

 

Exhaust filters have been of diesels for years now. I suspect engineers have a pretty good idea on how to implement them without causing problems.

 

One difference is higher exhaust gas temperatures on gasoline engines, though. And, diesels do have thermal efficiency to spare, where gasoline engines don't.

Also, there's also the consideration of... do you encourage the high cost (both to manufacturers and in long-term maintenance) of GPFs, or do you encourage increasing amounts of electrification to avoid running the engine altogether?

 

the valve gymnastics ability is there -

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Yeah, it's being used and called valvematic. Toyota has it in US Corolla eco. Maybe some other cars?

 

Of course we're already at 40% thermal efficiency but adding more would be a good thing.

Bob Wilson

 

Why does it have to be or the other? Set the emission limit fuel economy target, and let the market decide. The ICE still has a long life ahead of it; no reason to let it slack off because plug ins will be taking more market share.

I believe the 1.8L valvematic only available on the Eco here is the only 1.8L option on Corollas and Auris in Europe. US tends to get advanced Toyota tech last.

 

It's the never-ending debate over affordability versus emissions performance, really.

And, a port-injected motor like the one in the Prius is getting into the realm where the dominant PM emissions are coming from the tires, the brake pads (even with regenerative braking), and disturbed road dust.

In any case, though, the emissions regulations won't give a choice between, say, a hybrid with a GPF, and a range-extended vehicle without one - the range extended vehicle's required to meet regulations in a per-mile charge sustaining mode sense, not in a lifetime average sense. That means that even the range-extended vehicle will have the cost impact of the GPF, when it may make more sense to allow it higher CS emissions, if it helps the cost (and therefore accessibility) of the car for the CD mode operations that it usually gets used in.

Also, I suspect a range-extended vehicle will have a higher proportion of its CS operation in rural areas, too, where the CD operation occurs in cities.

 

As far as I'm aware, the particulate limits for gasoline engines will be at that of diesels. While a port injected engine can exceed that limit, I don't think there is any such engine in a car today. That leaves only direct injection gas engines getting an exhaust filter. I spoke of port injection needing a filter, but I see that day far off.

Direct injection improves engine efficiency and performance, but it is not the only option for doing some. Toyota's new 1.5L going in the European Yaris has a 13.5:1 compression ratio with port injection and using regular octane of that market. It's the benefits of direct injection without actually using DI. GPFs aren't going to become essentially mandatory on all gasoline engines like DPFs have on diesels.

I see most hybrids move to DI for the efficiency, and thus need a GPF. That is less likely with PHEVs. It depends upon the design philosophy. A short EV range one, like that of the Prime's, will likely make use of DI and whatever other efficiency tricks the ICE in the hybrid sibling has. But there are variables to consider. A PHEV that has increased performance in the electrical side over the plain hybrid might be able to not need the performance increase of DI, and could stick to a port injected engine.

For those PHEVs, hybrid efficiency is important when it comes to lowering the car's annual gasoline use. As the EV range extends, hybrid efficiency becomes less important for that reduction. A PHEV like the Volt and i3 REx can skip on the GPF to reduce the vehicle's price, by just skipping DI on the engine, which also has its own cost increase over a base engine.

 

Take this with a grain of salt: 2017 Hyundai Ioniq Hybrid: It misses lofty EPA expectation, but it's impossible to dislike | Automotive | stltoday.com

The Hyundai Ioniq hybrid is so doggone likable, we forgave the little guy when its real-world mpg wound up breaking our hearts.

In 225 miles of combined city/hwy driving, our Ioniq hybrid delivered to us 46 mpg, notably less than the 55 the EPA thought we'd get. . . .​

I just checked Fuelly and it looks like the car is close enough. This is not the first time we've seen poor MPG reported in a car report. No, I'm not giving up our Prius Prime and the stepped transmission of the Ioniq is not my cuppa tea.

Bob Wilson

 

Almost a personal note to Bob Wilson.

I appreciate your post ... responsible, well thought out and informative. I also appreciate Hill, bisco and Trollbait.

Regrettably, the Ioniq is off of my short list. I had high hopes for it, and seriously thought I would get one.
It is also regrettable that Toyota's design department has taken off on the tangent they have gone. I really believe the Prius is a far superior vehicle, I just can't stand the looks.

But here is my point: Today I was reading an article about millennials. The article pointed out that generally speaking, as a class, they are changing our society in a major way. (Generally) they are not interested in camping (we have acres of unsold 5th wheels and motor homes); playing golf (acres of beautiful little used real estate that is a burden on the tax payer); wearing expensive apparel, jewelry (vacant and closing department stores) .... and here is the 'kicker' .... driving new cars. Toyota is alleged to have re-designed the Prius for a more youthful client ... when 1) they can't afford a new car, and 2) they could care less about a new car. Sure ... there are exceptions.

In my day, a car was everything. I could not wait to get behind the wheel; visit the showroom and look at the new offerings; talk to mechanics and understand all the fine details, and read auto magazines from cover to cover. I wonder if (what I see as a US trend) is repeated in other parts of the world?

I have been reading the Tesla forum ..... but I'm growing weary of the constant debate about global warming, CO2 emissions, President Trump and the Paris accord. Why do the fringe (left and right) congregate around hybrids and EV's? Politics has invaded every discussion and every thought.

 

people change. who knows what each generation will be buying. sure we see trends, but tastes change with age. i sometimes think that the successful companies are not the smart ones, but the lucky ones.
bill gates? lucky
steve jobs? lucky
jeff bezos? lucky
elon musk? lucky.
sure, it takes smarts and dedication. but for all the lucky ones, how many fell by the wayside because they were unlucky?
how will car companies prosper if people lose interest? consolidation, cooperation, they'll make bets on the future. will the smart ones succeed, or those that work hardest, or the lucky?

 

Just sharing that we are on the same page about this:

Part of the problem is since the first Prius arrived in the USA, the automotive press, echoed by others, couldn't explain why anyone would buy one ... except to claim we are advocating some sort of 'green agenda.' As I've tried to point out, I've been an advocate of fuel efficiency since the 1970s BEFORE the first oil embargo.

Sad to say, I know too much chemistry, physics, and math to ignore the obvious but prefer to apply it to our cars. It is a shame we are often challenged by the "green lifestyle" accusations and "coal trolls" who could never understand that fuel efficiency is another type of 'car bling' like alloy wheels, spoilers, and a moon roof.

Bob Wilson

 

it's less worrysome for some (like me) to invest < ⅛ of 1% of one's PC time around FHOP. It's unlikely anyone wants to see my view in writing anymore than i do, anyway.

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Was the youthful demographic target for the Prius design decided upon before or after Toyota axed Scion?
As was said upon Scion's axing, most young people don't buy new cars because they can't afford a new one. There may have been an uptick of young people with new cars as the middle class was doing well, and parents helped with the car purchase. My first new car was a 1996 Taurus that my grandfather bought. Wasn't my first car; that was a 1986 Buick hand me down from him.

Cars have not gotten cheaper through the years, and student loan debt has climbed during that time. Whether or not they want a car to begin with, millennials might only be able to afford a used car.

Hybrids and EVs are still on the fringe side of sales in the US, and when you more than one person, you have politics.