Mythbusting and the facts known about the Outlander Phev.

[Claymore]

Haha, Christiaan Huygens was Dutch, wasn't he ? He didn't believe in infinitesimal calculus until the end of his life :lol:

Times, there are changin'

I've got a very nice Christiaan Huygens clock. The times are a changin' on that too!



JimB

 

[anko]

There seems to be this belief in several of our contributors here that a CVT simply has to be mechanical. The PHEV in serial mode has no mechanical link between the engine and the road wheels and hence it cannot possibly have a CVT - that is just plain stupid! It is no different to saying that an internal combustion engine has pistons and cylinders and hence the rotary engine in a Mazda is not internal combustion. Until recently, all cars with a CVT had a mechanical coupling between the engine and the wheels - but that is simply because nobody had worked out how to build a CVT that didn't have a mechanical coupling. Until recently, all vacuum cleaners relied on bags and filters - is a Dyson not a vacuum cleaner?

Maby, maybe you should talk about cvt instead of CVT :ugeek: By capitalizing the acronym you are imho no longer referring to just an effect or a concept. Same when you refer to Gravity instead of gravity. Or Vacuum Cleaner versus vacuum cleaner.

 

[jaapv]

....If the engine was connected to a pump that was circulating hydraulic fluid to a servo on the wheels would you say that it was disengaged from the wheels? In my Landcruiser with a conventional torque converter, the engine is coupled to an impeller that is dragging another impeller attached to the gearbox round - no mechanical linkage - is that disengaged from the wheels? Why can't you see that the combination of a generator and electric motor is just another power coupling mechanism?

I'm laughing now saying that it must be really depressing faced with idiots like me....I promise to desist after this last analogy (Neverfuel should hide 'cos it's another aviation one although not mentioning CSUs and definitely not tarring or feathering :? ).

More 'imagineering'....we're in our Vulcan on a long distance mission and eventually we need more motion lotion so we formate with the tanker and take on fuel to replenish our supply.

The fuel flowing from the tanker will allow us extended range or indeed to increase fuel flow rate by adding power to climb or to increase speed.

To my mind that is no different from the role of the ICE in the PHEV adding 'fuel' to the drive battery.

I couldn't describe the aviation refuelling as an example of a CVT therefore again, in my mind the PHEV one fails too.

Fortunately it doesn't matter what I think.

The really depressing thing is that I can't even sit down to read the papers without looking at this thread to what's been posted! Fat chance of me keeping my promise to post no more, but I'll try.

JimB

Well, my post that you were replying to was not particularly commenting on whether or not the PHEV has a CVT, more replying to your assertion that "In serial mode the engine is disengaged from the wheels so whether its rpm changes when you play with the throttle doesn't pass the 'so what' test surely?"

There seems to be this belief in several of our contributors here that a CVT simply has to be mechanical. The PHEV in serial mode has no mechanical link between the engine and the road wheels and hence it cannot possibly have a CVT - that is just plain stupid! It is no different to saying that an internal combustion engine has pistons and cylinders and hence the rotary engine in a Mazda is not internal combustion. Until recently, all cars with a CVT had a mechanical coupling between the engine and the wheels - but that is simply because nobody had worked out how to build a CVT that didn't have a mechanical coupling. Until recently, all vacuum cleaners relied on bags and filters - is a Dyson not a vacuum cleaner?

Well, if your definition of a CVT is two connected events that are completely dissociated, quite few posts on this thread are CVTs... :lol:

 

[Trex]

There seems to be this belief in several of our contributors here that a CVT simply has to be mechanical.

Yes because that is part of the standard definition.

The PHEV in serial mode has no mechanical link between the engine and the road wheels and hence it cannot possibly have a CVT - that is just plain stupid!

No not stupid. :lol: Required by the standard definition.

It is no different to saying that an internal combustion engine has pistons and cylinders and hence the rotary engine in a Mazda is not internal combustion.

No. Under the standard definition of a internal combustion engine a Wankel has to be included.

Until recently, all cars with a CVT had a mechanical coupling between the engine and the wheels - but that is simply because nobody had worked out how to build a CVT that didn't have a mechanical coupling.

No they cannot work out how to build a CVT that didn't have a mechanical coupling unless they redefine the standard definition.

Until recently, all vacuum cleaners relied on bags and filters - is a Dyson not a vacuum cleaner?

Yes because it still uses a partial vacuum as required under the standard definition.

 

[anko]

There seems to be this belief in several of our contributors here that a CVT simply has to be mechanical.

Yes because that is part of the standard definition.

Again, please reveal the source for "the standaard definition" so we can be done with this. Oh, and while you are at it, please explain how a hydrostatic CVT matches that definition

 

[Trex]

There seems to be this belief in several of our contributors here that a CVT simply has to be mechanical.

Yes because that is part of the standard definition.

Again, please reveal the source for "the standaard definition" so we can be done with this. Oh, and while you are at it, please explain how a hydrostatic CVT matches that definition

A continuously variable transmission (CVT) (also known as a single-speed transmission, stepless transmission, variable pulley transmission, or, in case of motorcycles, a twist-and-go) is an automatic transmission that can change seamlessly through a continuous range of effective gear ratios. This contrasts with other mechanical transmissions that offer a finite number of gear ratios. Wikipedia

Note that last sentence and the words with "other mechanical transmissions".

Hydrostatic transmissions use a mechanically adjustable variable displacement pump for instance which would help it fall under this definition.
Hydraulic fluid which has mechanical properties would also help bring it under this definition.
Pumping fluids is mechanical don't you agree?

It is definitely not electrical.

 

[anko]

Of course it is not electrical, but that is not the point. Hydrostatic CVTs exists and if they are not mechanical, that would mean that CVTs do not have to be mechanical. And if CVTs do not have to be mechanical, why can't they be electrical?

Just google "hydrostatic versus mechanical". Will result in plenty of hits. For example http://machinedesign.com/mechanical-drives/hydrostatic-drives, which says:

Hydrostatic drives are widely recognized as an excellent means of power transmission when variable output speed is required. Typically outperforming mechanical and electrical variable-speed drives and gear-type transmissions, they offer fast response, maintain precise speed under varying loads, and allow infinitely variable speed control from zero to maximum.

Unlike gear transmissions, hydrostatics have a continuous power curve without peaks and valleys, and they can increase available torque without shifting gears. But despite the superior performance of hydrostatics, a major drawback has been higher cost compared to their mechanical counterparts.

This suggests that hydrostatic and mechanic are two different things. Then again, https://en.wikipedia.org/wiki/Hydrostatics talks says:

Hydrostatics is the branch of fluid mechanics that studies incompressible fluids at rest

which suggest hydrostatics is a special kind of mechanics.

I am lost .... :lol:

 

[Trex]

Of course it is not electrical, but that is not the point. Hydrostatic CVTs exists and if they are not mechanical, that would mean that CVTs do not have to be mechanical. And if CVTs do not have to be mechanical, why can't they be electrical?

Just google "hydrostatic versus mechanical". Will result in plenty of hits. For example http://machinedesign.com/mechanical-drives/hydrostatic-drives, which says:

Hydrostatic drives are widely recognized as an excellent means of power transmission when variable output speed is required. Typically outperforming mechanical and electrical variable-speed drives and gear-type transmissions, they offer fast response, maintain precise speed under varying loads, and allow infinitely variable speed control from zero to maximum.

Unlike gear transmissions, hydrostatics have a continuous power curve without peaks and valleys, and they can increase available torque without shifting gears. But despite the superior performance of hydrostatics, a major drawback has been higher cost compared to their mechanical counterparts.

This suggests that hydrostatic and mechanic are two different things. Then again, https://en.wikipedia.org/wiki/Hydrostatics talks says:

Hydrostatics is the branch of fluid mechanics that studies incompressible fluids at rest

which suggest hydrostatics is a special kind of mechanics.

I am lost .... :lol:

:lol:
As a person that did a fluid mechanics course (we use hydraulics in the machinery we build) over 30yrs ago I would not not like to think my teacher was having me on. He described it as a branch of mechanics.

 

[maby]

Well, in the first place, I would suggest that Wikipedia, while important, is not the font of all knowledge that it is sometimes considered to be.

Secondly, definitions change in order to follow developments in technology. You are quite happy to describe a rotary engine as internal combustion on the grounds that the fuel is burned within the main body of the engine rather than outside it, but you insist that a transmission that unquestionably delivers a continuously variable ratio cannot be CVT because it is not mechanical. It would be perfectly possible to take the design of the PHEV transmission, package it up in a black box that just had an input shaft, an output shaft and a control input (you could even make that mechanical if you really wanted!) and program up the firmware to produce a response curve that was indistinguishable from an old DAF box full of cones, gears and belts. That is a CVT and anyone that can't see that does not qualify as an engineer. Are you going to say that the PHEV transmission is not a CVT because it is not packaged as a black box? If you took the casing off a DAF transmission so that it became four cones linked by a drive belt, would it cease to be a CVT?

 

[jaapv]

As far as I am aware the original DAF transmission on the DAF 33 was not encased, it was just hidden under the floor.

Anyway, your Wankel analogy fails, as that is still all mechanical. The essence of an ICE is not pistons, it is internal combustion. Otherwise a Stirling Engine or steam engine would come within the definition.

In any case, even if one takes the mechanical aspect out of the PHEV system, it still does not behave like a CVT anyway, unless under a strictly defined set of circumstances. i.e. Series Hybrid. When running EV there is no transmission from the ICE at all, when running as parallel hybrid it is a fixed ratio transmission.

 

[Trex]

Well, in the first place, I would suggest that Wikipedia, while important, is not the font of all knowledge that it is sometimes considered to be.

Secondly, definitions change in order to follow developments in technology. You are quite happy to describe a rotary engine as internal combustion on the grounds that the fuel is burned within the main body of the engine rather than outside it, but you insist that a transmission that unquestionably delivers a continuously variable ratio cannot be CVT because it is not mechanical. It would be perfectly possible to take the design of the PHEV transmission, package it up in a black box that just had an input shaft, an output shaft and a control input (you could even make that mechanical if you really wanted!) and program up the firmware to produce a response curve that was indistinguishable from an old DAF box full of cones, gears and belts. That is a CVT and anyone that can't see that does not qualify as an engineer. Are you going to say that the PHEV transmission is not a CVT because it is not packaged as a black box? If you took the casing off a DAF transmission so that it became four cones linked by a drive belt, would it cease to be a CVT?

Sorry maby as an engineer I have to deal with facts and standard definitions.

For example, this is a simple one, lets say I redefine the whitworth thread. I will call it a thingamajig thread.
I am sure you can see where this is going. Not very professional.

Now lets look at the Phev. Series mode is nothing but a petrol-electric transmission. Been around for a long time. Not a new invention.
No matter how much I search I cannot see it described as a CVT. I wonder why?

I know. Pick me, pick me. Because it is not. :lol:

 

[ChrisMiller]

This is all a fascinating discussion of what different people understand the letters CVT to mean. But if I may quote Richard Feynman describing what he learnt from his father:

“See that bird?” he says. “It’s a Spencer’s warbler.” (I knew he didn't know the real name.) “Well, in Italian, it’s a Chutto Lapittida. In Portuguese, it’s a Bom da Peida. In Chinese, it’s a Chung-long-tah, and in Japanese, it’s a Katano Tekeda. You can know the name of that bird in all the languages of the world, but when you’re finished, you’ll know absolutely nothing whatever about the bird. You’ll only know about humans in different places, and what they call the bird. So let’s look at the bird and see what it’s doing—that’s what counts.” (I learned very early the difference between knowing the name of something and knowing something.)

So whether we choose to describe the PHEV as having a CVT or not is irrelevant, it's what it actually does that matters. And as I (now, thanks to this thread) understand it: when operating in parallel mode, the engine's rpm is a fixed multiple of the rotational speed of the wheels; whereas in serial mode, it isn't. Does anyone disagree, and (if so) why? If we're all agreed, we can move on to deciding how many angels can dance on the head of a pin.

 

[Claymore]

.........we can move on to deciding how many angels can dance on the head of a pin.

Chris, are these standard or non standard size pins and angels?

:twisted:

JimB

 

[ChrisMiller]

Chris, are these standard or non standard size pins and angels?

And can they do the fandango?

 

[greendwarf]

Well, in the first place, I would suggest that Wikipedia, while important, is not the font of all knowledge that it is sometimes considered to be.

And it's not admissible as evidence in court, as it can be edited by anyone to state whatever you want.

 

[Trex]

Well, in the first place, I would suggest that Wikipedia, while important, is not the font of all knowledge that it is sometimes considered to be.

And it's not admissible as evidence in court, as it can be edited by anyone to state whatever you want.

The source material certainly could be evidence in court. Wikipedia state:

One of the key policies of Wikipedia is that all article content has to be verifiable. This means that a reliable source must be able to support the material. All quotations and any material whose verifiability has been challenged or is likely to be challenged must include an inline citation of a source that directly supports the material. This also means that Wikipedia is not the place for original work, archival findings that have not been published, or evidence from any source that has not been published.

But you knew that all along and was just pulling our legs. :lol:

 

[greendwarf]

Well, in the first place, I would suggest that Wikipedia, while important, is not the font of all knowledge that it is sometimes considered to be.

And it's not admissible as evidence in court, as it can be edited by anyone to state whatever you want.

The source material certainly could be evidence in court. Wikipedia state:

One of the key policies of Wikipedia is that all article content has to be verifiable. This means that a reliable source must be able to support the material. All quotations and any material whose verifiability has been challenged or is likely to be challenged must include an inline citation of a source that directly supports the material. This also means that Wikipedia is not the place for original work, archival findings that have not been published, or evidence from any source that has not been published.

But you knew that all along and was just pulling our legs. :lol:

I'm afraid not - there are lots of articles without any source material other than the author him/herself. As far as ease of editing is concerned, one of my colleagues altered an article to demonstrate the unreliability point in court. :lol:

 

[ian4x4]

This topic should have been just titled 'MYTHBUSTING'.

I have enjoyed hours of reading this topic and getting misdirected into various suggested references.

I think we are doing the Outlander PHEV (and indeed all EV/PHEV/HYBRID cars) a mis-service by concentrating on the mechanical bits and ignoring the millions of line of code which can make it do anything the designers want.

I'm sorry to say that things change, both what we think will be possible, and the means of achieving our aims.

I am retired and I have seen the same things done mechanically, electro-mechanically, electronically (thermonically & solid state), and digitally.

Shouldn't we just produce a unique definition for the Outlander PHEV's drive train.

PS I have also learnt a lot about the regular contributors to this forum. Keep it up.

Thank You

 

[Trex]

I'm afraid not - there are lots of articles without any source material other than the author him/herself.

And there are lots of articles with source material other than the author him/herself. Their voluntary editors try to keep up.

As far as ease of editing is concerned, one of my colleagues altered an article to demonstrate the unreliability point in court. :lol:

Yes I know anyone can edit and again their voluntary editors try to keep up. Including banning IP addresses of offenders.
You do know that your colleague committed vandalism? :evil:

And as a person that knows of this vandalism you could be guilty of being an accessory. :twisted:

Wikipedia:Counter-Vandalism Unit is specifically set up try and stop people like your colleague.
The Counter-Vandalism Unit (CVU) is a Wikipedia project whose aim is to help detect and remove vandalism on Wikipedia by using tools and experience, and to provide advice on dealing with vandals.

They have a Wikipedia:Counter-Vandalism Unit/Academy to train persons for their Counter-Vandalism Unit.
The CV training program is designed to help new and/or inexperienced users who wish to assist with maintenance tasks to understand the basic principles of countering vandalism on Wikipedia, and to introduce the various 3rd party applications and helper scripts available to users with sufficient experience.

So greendwarf every time that phone rang or someone knocked on the door I would be worried if I were you. :?

They could be coming to get you. :shock:

 

[jaapv]

Still, there is an amazing amount of misinformation and plain mistakes in Wikipedia. Despite its pretensions, it is not the sum of all human knowledge. I had a run-in with the editors over my father's obituary. Not very professional and rather biased and ignorant, in my experience.