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First time eDrive and xDrive tech has been combined in one vehicle

BMW has unveiled the Concept X5 eDrive, which will be showcased at the New York International Auto Show. Although the vehicle is labeled as a concept, it’s a dead ringer for the production plug-in hybrid version of BMW’s popular crossover that it plans to bring to market sometime within the next year or two.
 
The hybrid drive system gets its primary motivation from a 245hp turbocharged 4-cylinder engine. That gas engine is combined with a 95hp/184 lb-ft electric motor developed by the BMW Group. Power for the electric motor comes from a lithium-ion battery pack (which is mounted under the cargo area) that can charge from any wall outlet.
 
The Concept X5 eDrive can drive on electricity alone for up to 20 miles at speeds up to 75 mph. BMW says that the car will have an average fuel consumption of over 74.3 mpg in the EU testing cycle (which means we’ll likely see less than half of that quoted figure under EPA guidelines). BMW says that the X5 concept can reach 62mph in under 7-seconds.

 
The Concept X5 eDrive is the first from BMW that uses its xDrive all-wheel-drive system paired with eDrive hybrid technology.
 
The concept also has a ConnectedDrive system that helps plan routes and lists the location of charging stations on the GPS map. This allows the driver to find a charging station when they are around town in electric mode.

Source: BMW



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RE: Tesla!
By snhoj on 4/22/2014 8:43:24 PM , Rating: 2

quote:
Drag is an aerodynamic effect; rolling resistance is a separate thing, and it's effects on the net friction that the vehicle must overcome to accelerate and move is not substantial. You are driving this conversation off topic by fixating on minutia.

Really, well all those poor fools buying low rolling resistance tires are just wasting their money then.

quote:
No, I didn't misunderstand you. The fact that the car is heavy contributes to its inefficiency. Rolling resistance is largely a factor of the tires - their width and their inflation pressure.

I bring up the Tesla’s weight and say it will increase rolling resistance, you say no the Tesla is heavy, I say that’s what I meant the Tesla is heavy, you say I didn’t misunderstand you the Tesla is heavy. Even when I agree with you, you have to disagree with me. Yes increasing rolling resistance will make the car less efficient. Yes I understand that rolling resistance is mostly about tires

quote:
You've already made two 'questionable' assumptions in an effort to make the numbers look "good" or seem right...but lets' examine this with your figures.

OK doing it the hard way. Using a published rolling resistance coefficient for a tire similar to what is fitted to the Tesla model S.
“RRC for the Goodyear Eagle GT HR (probably the closest to the RS-A2s) is 0.01217.”
This really quite close to the assumed coefficient calculated at 0.01327. So eliminating my questionable assumptions gives us 6.15 kW consumed by rolling resistance at 55 MPH. Drive efficiency declines to 81.2%. Note this 81.2% accounts for any braking and other energy losses unrelated to drive line efficiency. No questionable assumption left.

quote:
Going by what you cite as Tesla's 14.6 kW (20 HP) figure to sustain 55 MPH, we can simply scale up the power required for higher speeds, because:

Power:
= Work/Time
= Force x Distance/Time
= Force x Velocity

Air resistance is proportional to the square of the speed, and going from 55 to 80 MPH is a 25 MPH increase, or a 1.46 increase in velocity.

We square 1.46 to get 2.13, which is the new force.

The energy consumption of a vehicle virtually all comes back to two factors. Weight and aero drag. First you say weight will make a car inefficient then you totally disregard it in this calculation. So which is it, is weight in or is it out. Does weight generate a drag force which must be overcome or can we say its basically zero so we can just ignore it.

quote:
14.6 kW x 1.46 x 2.13 = 45.4 kW

So to drive your model S at 80 MPH using your 14.6 kW @ 55 MPH figure, it takes 45.4 kW or 60 HP - your results are off by quite a bit...at this rate your effective range will be around 150 miles, because remember, 45 kW of engine output will draw MORE than 45 kW from the batteries.

Like I said before, if you know how much power it takes to go a certain speed, you can figure out how much more (or less) you would need for a change in velocity using some very basic math.

A bit too basic unfortunately. It seems to have escaped your attention that aero drag scales with the cubic function of velocity when it comes to power requirements and including all the drag that doesn’t scale will dramatically exaggerate your figures. I told you exactly what the aero drag power requirements were at 55 MPH yet you choose to ignore that and generate more nonsense. If I apply a bit of reducto ad absurdum to your argument that all drag is aero drag and therefore scales to the square function of velocity then at zero velocity the car would exist in a frictionless state with only its inertia to resist motion if on a level surface. You would have no trouble pushing a 4700lb car with your pinky finger. It only takes a small force and a bit of time to overcome inertia.
quote:
Stepping up the voltage costs efficiency. I do not know what the operating voltage of the model S inverter happens to be, however I am well aware that it regulates its output voltage which is how it controls engine speed.

Actually I’ve been trying to tell you that it regulates its output amperage and it controls motor torque not speed. EV’s would be hard to drive if the motor controller and accelerator position regulated motor speed.
quote:
When I launch a car, I rev the engine up to a specific RPM and drop the clutch. The engine will stay at or near the launch RPM and then increase. There is nothing that says I cannot launch the car AT the redline if my tires have enough traction, thus having the engine producing almost all of its power AND torque from a stop.

EV’s don’t work that way. The power provided at a full throttle launch will ramp from some initial value required to overcome losses up to peak power at peak power RPM and speed.
quote:
The key point is that the batteries will be discharging at 850A or more when the drive program allows 'full power'...and it will be close to full power from a stop if you floor it and have the car in "performance mode".

Wrong. Peak amps is only drawn from the battery at peak power. Peak power occurs around 7000RPM. Peak torque is a band from 0 to7000 RPM. 7000 RPM by my calculation would occur around 57 MPH. Don't forget EV's control torque. You don't get "full power" but full torque when you floor it.

quote:
False. The idling engine is producing torque and therefore power. Simply because the car is not moving does not mean efficiency is 0%.

And that idling torque is totally consumed internally overcoming pumping losses and bearing friction. Energy out /energy in=efficiency. Zero energy out equals zero efficiency. If you happen to have the AC on it might not be completely zero efficiency granted. When it comes to efficiency and cars we can generate efficiency numbers for elements of the car but the car as a whole is a total loss system so what passes for an efficiency measure for the vehicle in totality is actually a rate of consumption.

quote:
0% efficiency means that the electric motor is drawing current but not moving, and since it is not moving it is not producing power so efficiency is 0%. When the motor draws current and does not move, the energy radiates as heat. It is not a difficult concept to fathom, even though it is only for a brief moment.

I didn’t disagree with you.
quote:
Tesla is trying to achieve an electric car that replaces gasoline cars, and that's just not happening. It takes too long to charge vs filling up with fuel, using the A/C can have a big impact on range, as can loading the car up with passengers and cargo. Reliability is also in question, and there are already plenty of reports from owners who have experienced problems like the car completely shutting off (while being driven) and being unable to start.


Actually I was thinking more about what their customers were hoping to achieve. Personally I would like to get off blood oil.


RE: Tesla!
By EricMartello on 5/3/2014 1:08:35 AM , Rating: 2
quote:
Really, well all those poor fools buying low rolling resistance tires are just wasting their money then.


Pretty much, and they're sacrificing handling and braking ability for a negligible "improvement" in fuel efficiency.

quote:
The energy consumption of a vehicle virtually all comes back to two factors. Weight and aero drag. First you say weight will make a car inefficient then you totally disregard it in this calculation. So which is it, is weight in or is it out. Does weight generate a drag force which must be overcome or can we say its basically zero so we can just ignore it.


I didn't disregard weight. Weight has already been accounted for by the baseline value, which I scaled.

It's really very simple and I'll repeat it for you: if we know how much power it takes for a vehicle to move at a certain speed on a level surface, we can use a simple scaling formula to ascertain the power required at higher or lower speeds.

quote:
A bit too basic unfortunately. It seems to have escaped your attention that aero drag scales with the cubic function of velocity when it comes to power requirements and including all the drag that doesn’t scale will dramatically exaggerate your figures.


False. The primary resisting force is aerodynamic drag. Again, your fixation on minutia in an effort to obfuscate the real point only makes you look like someone who can't accept that they were wrong.

quote:
I told you exactly what the aero drag power requirements were at 55 MPH yet you choose to ignore that and generate more nonsense. If I apply a bit of reducto ad absurdum to your argument that all drag is aero drag and therefore scales to the square function of velocity then at zero velocity the car would exist in a frictionless state with only its inertia to resist motion if on a level surface. You would have no trouble pushing a 4700lb car with your pinky finger. It only takes a small force and a bit of time to overcome inertia.


Verbal diarrhea is not the mark of someone who knows what they're talking about. You seem to be sliding into a pit of repetition peppered with stupidity. Next thing we'll have you telling us that climate change affects the tesla's efficiency because vegetable.

quote:
Actually I’ve been trying to tell you that it regulates its output amperage and it controls motor torque not speed. EV’s would be hard to drive if the motor controller and accelerator position regulated motor speed.


That's incorrect. It uses a PWM type of speed control, which limits voltage. Current limiting is an automatic result of pulsing the drive voltage at lower frequencies when the car is moving at lower speeds, and higher frequencies when the car is moving faster. The pwm system allows for "real time" feedback on what the engine is doing and allows its performance and response to be tuned. If you were to simply make a direct "always on" connection to the motor from the inverter, the car would probably have trouble gaining traction.

FYI direct current limiting causes the excess current to be bled off as heat. That would be a very inefficient method of regulating the engine speed...and incidentally it's why tesla uses a PWM speed control. And yes, it's called a SPEED CONTROL not a torque control.

quote:
EV’s don’t work that way. The power provided at a full throttle launch will ramp from some initial value required to overcome losses up to peak power at peak power RPM and speed.


I'm quite aware of the differences; but you've cleverly managed to miss my point yet again. The point I was making, is that while electric cars may have "full torque" from 0 RPM, launching a gasoline car from a stop can be done in such a way that you have nearly full power and torque from a stop. It's called launching for a reason.

Since the inverter regulates the motor using a PWM type of system, full throttle doesn't equal a full-on connection between the motor and power source. The entire powerband is regulated, and that means the power is always pulsed, i.e. on and off.

quote:
Wrong. Peak amps is only drawn from the battery at peak power. Peak power occurs around 7000RPM. Peak torque is a band from 0 to7000 RPM. 7000 RPM by my calculation would occur around 57 MPH. Don't forget EV's control torque. You don't get "full power" but full torque when you floor it.


The problem with people like you is that you believe you know what you're talking about but don't. Do you think that the motor spinning at 7,000 RPM in free air (no load) will draw the same current as it would pushing the weight of the car down a drag strip (full load)?

The amount of current drawn is inversely proportional to the delta between the no-load speed of the motor and the motor speed reduction when a is load placed on said motor.

What does that mean?

When there is NO LOAD on the motor, it is spinning at it's full RPM based on whatever the input voltage is and the current drawn is minimal.

When there is a load on the motor, the motor speed drops which causes the voltage to drop. The motor draws more current as it attempts to accelerate to its no-load RPM, or to a point that matches its input voltage.

Please shut up about your idiotic and incorrect calculations and moronic theories about how electric motor drive systems work. You really do not know what you are talking about here and it's just getting tedious repeating myself.

quote:
And that idling torque is totally consumed internally overcoming pumping losses and bearing friction.


The amount of power consumed by the belt driven accessories is minimal at idle. Torque is not consumed; it is transferred.

quote:
Actually I was thinking more about what their customers were hoping to achieve. Personally I would like to get off blood oil.


Blood oil? Yeah, I'm not surprised you'd believe in something as retarded as that.

You should be more concerned with your liberalism infection and the fact that it is steadily making you dumber. Have you considered just staying home all the time, thus eliminating the need for a vehicle altogether?


RE: Tesla!
By snhoj on 5/7/2014 8:14:22 PM , Rating: 2
quote:
I didn't disregard weight.

Oh yes you did. I for one happen to understand that zero squared is still zero.

quote:
Weight has already been accounted for by the baseline value, which I scaled.

Yes but you than scale it with total disregard of weight solely as a function of speed.

quote:
It's really very simple and I'll repeat it for you: if we know how much power it takes for a vehicle to move at a certain speed on a level surface, we can use a simple scaling formula to ascertain the power required at higher or lower speeds.

Repeating the same flawed argument over and over again doesn’t make it correct.

quote:
False. The primary resisting force is aerodynamic drag. Again, your fixation on minutia in an effort to obfuscate the real point only makes you look like someone who can't accept that they were wrong.

I don’t accept I’m wrong because I’m not and I have proved it. Minutia it’s not. Have you ever tried to push a 4700lb vehicle?

quote:
Verbal diarrhea is not the mark of someone who knows what they're talking about. You seem to be sliding into a pit of repetition peppered with stupidity. Next thing we'll have you telling us that climate change affects the Tesla's efficiency because vegetable.

I see name calling and personal attacks but I don’t see an argument. I guess you lost that one.

quote:
That's incorrect. It uses a PWM type of speed control, which limits voltage. Current limiting is an automatic result of pulsing the drive voltage at lower frequencies when the car is moving at lower speeds, and higher frequencies when the car is moving faster. The pwm system allows for "real time" feedback on what the engine is doing and allows its performance and response to be tuned.

If you can measure it you can control a system according to it.

quote:
If you were to simply make a direct "always on" connection to the motor from the inverter, the car would probably have trouble gaining traction.

I never said anything about always on.

quote:
FYI direct current limiting causes the excess current to be bled off as heat. That would be a very inefficient method of regulating the engine speed...and incidentally it's why tesla uses a PWM speed control. And yes, it's called a SPEED CONTROL not a torque control.

Who said anything about current limiting with an additional load? The Back EMF of the motor and the resistance of the windings can be used to control the current if you chop the voltage accordingly. I find it really hard to believe that you think you cannot control the torque output of a motor. Really?

quote:
I'm quite aware of the differences; but you've cleverly managed to miss my point yet again. The point I was making, is that while electric cars may have "full torque" from 0 RPM, launching a gasoline car from a stop can be done in such a way that you have nearly full power and torque from a stop. It's called launching for a reason.

I didn’t miss the point. The point was redundant. Just because you can have full power and massive torque and convert your tires to smoke at launch doesn’t mean that EV’s must have full power available at launch. They don’t and they don’t need to unless the objective is to make lots of expensive smoke.

quote:
Since the inverter regulates the motor using a PWM type of system, full throttle doesn't equal a full-on connection between the motor and power source. The entire powerband is regulated, and that means the power is always pulsed, i.e. on and off.

Yes, with the notable exception of exactly at peak power but only for DC systems.

quote:
The problem with people like you is that you believe you know what you're talking about but don't. Do you think that the motor spinning at 7,000 RPM in free air (no load) will draw the same current as it would pushing the weight of the car down a drag strip (full load)?

WTF. Of course not. Where are you getting this stuff from?

quote:
Please shut up about your idiotic and incorrect calculations and moronic theories about how electric motor drive systems work. You really do not know what you are talking about here and it's just getting tedious repeating myself.

When you get abusive do people pay more attention to what you say? Does it improve your credibility?

quote:
The amount of power consumed by the belt driven accessories is minimal at idle. Torque is not consumed; it is transferred.

When a system is in equilibrium, i.e. idling at a constant RPM, any torque produced by the engine must be matched by an equal and opposite torque or the engine would not be in a state of equilibrium and would either be accelerating or decelerating. When the drive is disengaged that torque will be predominantly internal losses. Physics 101. I’d be interested to hear your take on where that torque is being transferred to.


RE: Tesla!
By EricMartello on 5/10/2014 12:49:57 AM , Rating: 1
quote:
Oh yes you did. I for one happen to understand that zero squared is still zero.


If you are calculating the approximate power required for a car to move at a certain speed without knowing the power required to move at ANY speed in the first place, then weight would be part of that equation...but since we already knew how much power it takes to move the car at a given speed, weight has already been factored, and therefore we can scale power, as I did. Not sure how many times I have to repeat this until you get it.

quote:
Yes but you than scale it with total disregard of weight solely as a function of speed.


No, I did not. WEIGHT WAS ALREADY FACTORED IN TO DETERMINE THE BASE VALUE OF POWER REQUIRED TO TRAVEL 55 MPH. The car does not get heavier if it moves at a faster speed; the only thing that changes is the wind resistance.

You're really obsessing over nothing when your claims of superior efficiency have already been dispelled, so get over it and learn some basic math while you're at it.

quote:
Repeating the same flawed argument over and over again doesn’t make it correct.


And yet here you are, posting again, still wrong.

quote:
I don’t accept I’m wrong because I’m not and I have proved it. Minutia it’s not. Have you ever tried to push a 4700lb vehicle?


The only thing you've proven is that you flunked high school physics class, and even with your constant referencing of google and wikipedia, you still can't get it right. Have you ever pushed a car that weighs 2,000 LBS at 40 MPH and 4,000 LBS at 80 MPH? L...O...L

quote:
Who said anything about current limiting with an additional load? The Back EMF of the motor and the resistance of the windings can be used to control the current if you chop the voltage accordingly. I find it really hard to believe that you think you cannot control the torque output of a motor. Really?


Oh that's a new one - you restate things I've said and then try to present it as what you've been saying all along. LOL Nice job, but you are still not grasping the basic functions of an electric motor and its respective speed controller.

In the context of an electric motor, VOLTAGE is adjust to control the engine speed. A turning motor is producing power, which INCLUDES torque...however you incorrectly continue to refer to the speed controller as a torque modulator, and even suggest that the motor speed is regulated by limiting current to the engine when increasing/decreasing voltage is all that's necessary.

quote:
I didn’t miss the point. The point was redundant. Just because you can have full power and massive torque and convert your tires to smoke at launch doesn’t mean that EV’s must have full power available at launch. They don’t and they don’t need to unless the objective is to make lots of expensive smoke.


Actually it's not redundant, because it completely shatters the whole "full torque from zero RPM" line that the ignorant EV humpers cite as a major benefit of electric motors over gasoline engines...apparently they don't know how to launch a gasoline car to maximize its acceleration and assume that all acceleration happens off-idle...and if you launch correctly your tires will hook and you will accelerate quite nicely.

quote:
When you get abusive do people pay more attention to what you say? Does it improve your credibility?


I'm hardly being abusive...maybe you're just too whiny and thin-skinned.

quote:
When a system is in equilibrium, i.e. idling at a constant RPM, any torque produced by the engine must be matched by an equal and opposite torque or the engine would not be in a state of equilibrium and would either be accelerating or decelerating. When the drive is disengaged that torque will be predominantly internal losses. Physics 101. I’d be interested to hear your take on where that torque is being transferred to.


You probably spent hours writing this statement, even soliciting your asian friends for help, only to end up "not getting it".

Your previous statement attempted to portray the engine accessories as requiring all or most of the torque of the engine at idle - which is false. The power steering pump, the water pump, alternator and A/C unit combined place a relatively minor parasitic load on the engine, whether it's idling or at its redline.

Yes, I'm sure you thought you are brilliant for pointing out newton's 3rd law, but that is obvious that was never in question or in doubt.

Torque is a force, so it is transferred rotationally along an axis. It is not "consumed". Power is consumed, and power is torque x RPM.

An axle spinning at a certain RPM being driven with a fixed amount of torque can continue turning so long as the load placed on the axle does not exceed the amount of torque which is driving it...however if you increase the load on the axle without increasing the torque, the RPM will decline. Get it? That is power being consumed - the torque does not change.

Go back to school.


RE: Tesla!
By snhoj on 5/11/2014 7:03:13 PM , Rating: 2
quote:
If you are calculating the approximate power required for a car to move at a certain speed without knowing the power required to move at ANY speed in the first place, then weight would be part of that equation...but since we already knew how much power it takes to move the car at a given speed, weight has already been factored, and therefore we can scale power, as I did. Not sure how many times I have to repeat this until you get it.

Because weight doesn’t change with speed, the drag force due to weight doesn’t change with speed. Therefore the power consumed due to weight scales linearly with velocity or is proportional to mass times velocity. The drag force due to aero drag scales with the square of velocity. Therefore the power consumed due to velocity (aero drag) scales with the cube of speed or is proportional to velocity cubed. Adding the results of the linear function and the cube function creates a third function in which mass and velocity still feature separately. That third function is NOT proportional to the square of speed. Mass times velocity is NOT a constant and so cannot be factored out along with the other constants when figuring out proportionality. I’m not wrong about this.
quote:
so get over it and learn some basic math while you're at it.

quote:
quote:
Minutia it’s not. Have you ever tried to push a 4700lb vehicle?


That went straight over your head. The Tesla’s weight and tires will result in a rolling resistance of 56lb force. If you think that is insignificant to the point of being practically zero when compared to aero drag then what else can I say. Either you can’t understand or you won’t understand and neither of these makes you look good.

quote:
Oh that's a new one - you restate things I've said and then try to present it as what you've been saying all along. LOL Nice job, but you are still not grasping the basic functions of an electric motor and its respective speed controller.

An EV is not like one of your model aircraft and the correct terminology is Motor controller specifically so people like you won’t become confused. I posted this on the 4/16/2014 in this thread so it is what I have been saying all long.
quote:
In an EV we don't want to control the speed of the motor but the torque it puts out. If the accelerator position controlled speed the vehicle would be very difficult to drive. Hence the motor controller manipulates the current by manipulating the voltage but the voltage doesn't bear any direct relationship to the accelerator position. None of this is in disagreement with what you have said I’m just trying to add a different perspective. As for load when you encounter a hill the driver must adjust the accelerator pedal to maintain speed (as you currently do in your ICE powered car) increasing the current to maintain the voltage.


quote:
Actually it's not redundant, because it completely shatters the whole "full torque from zero RPM" line that the ignorant EV humpers cite as a major benefit of electric motors over gasoline engines...apparently they don't know how to launch a gasoline car to maximize its acceleration and assume that all acceleration happens off-idle...and if you launch correctly your tires will hook and you will accelerate quite nicely.

The advantage of full torque from zero is not having to have a clutch (or torque converter).The advantage is not having to have a clutch. It’s a mechanical simplification. In the case of Tesla the range of the motor is so broad that it also doesn’t need a gearbox and can make do with a single reduction ratio. A further mechanical simplification. The net result of this is lower weight better reliability and reduced cost.

quote:
I'm hardly being abusive...maybe you're just too whiny and thin-skinned.

Denial followed by more abuse. That’s funny LOL.

quote:
You probably spent hours writing this statement, even soliciting your asian friends for help, only to end up "not getting it".

Your previous statement attempted to portray the engine accessories as requiring all or most of the torque of the engine at idle - which is false. The power steering pump, the water pump, alternator and A/C unit combined place a relatively minor parasitic load on the engine, whether it's idling or at its redline.

Yes, I'm sure you thought you are brilliant for pointing out newton's 3rd law, but that is obvious that was never in question or in doubt.

Torque is a force, so it is transferred rotationally along an axis. It is not "consumed". Power is consumed, and power is torque x RPM.


So if torque is not consumed and power is consumed and power is torque x RPM then really it is just RPM that is being consumed?? LOL. You’re funny.

quote:
An axle spinning at a certain RPM being driven with a fixed amount of torque can continue turning so long as the load placed on the axle does not exceed the amount of torque which is driving it...however if you increase the load on the axle without increasing the torque, the RPM will decline. Get it? That is power being consumed - the torque does not change.

Go back to school.


All that and you still haven’t said were torque in an idling engine is being transferred to.

How does it feel Eric being bested by a “dim-witted buffoon”. Nothing in this world is free Eric not even cheap shots.


RE: Tesla!
By EricMartello on 5/15/2014 1:55:58 AM , Rating: 1
quote:
Because weight doesn’t change with speed, the drag force due to weight doesn’t change with speed.


Repeating what I said...brilliant, you're learning that you can be right more often if you just repeat what I say.

quote:
Therefore the power consumed due to weight scales linearly with velocity or is proportional to mass times velocity.


But then you decide to be a liberal, keep talking, and be wrong again when you could have just shut up and spared yourself further humiliation.

Let's talk about this thing called MOMENTUM. The weight of a vehicle at speed does not change, and if you are traveling at a constant velocity YOU ARE NOT ACCELERATING and therefore the effects of mass do not change.

Yes, it takes more power to accelerate a larger mass to a certain speed BUT once at speed, and that's what we're talking about here in case you totally missed it, there is no difference in power required to move the object due to mass.

The PRIMARY resisting force is wind resistance when traveling at a higher speed. That...is...all.

quote:
The drag force due to aero drag scales with the square of velocity. Therefore the power consumed due to velocity (aero drag) scales with the cube of speed or is proportional to velocity cubed.


Funny, this guy lost the battle, the audience went home but he's still so sure he's right. Then he says this and proves that he still doesn't get it.

quote:
Adding the results of the linear function and the cube function creates a third function in which mass and velocity still feature separately. That third function is NOT proportional to the square of speed. Mass times velocity is NOT a constant and so cannot be factored out along with the other constants when figuring out proportionality. I’m not wrong about this.


Oh, you are terribly wrong and if you think you're not then you are fitting the very definition of stupid.

We are talking about a constant velocity, not a change in velocity (acceleration). Mass doesn't change due to speed, and once a mass is moving it has this thing called momentum.

Momentum, in the case of a moving car, is effectively a constant that will scale linearly with velocity - and that makes sense because like I told you before, the car weighs exactly the same at 55 MPH as it does at 80 MPH.

The power requirements I provided to you are accurate...period...and more importantly, you were wrong altogether about EVs being more efficient so trying to make your "last stand" here and failing isn't doing you any favors.

quote:
That went straight over your head. The Tesla’s weight and tires will result in a rolling resistance of 56lb force. If you think that is insignificant to the point of being practically zero when compared to aero drag then what else can I say. Either you can’t understand or you won’t understand and neither of these makes you look good.


No, I simply disregard irrelevant statements such as this one...but keep talking about rolling resistance, man...like you even know what that is. It's really helping you get your point across, except your point that EVs are "more efficient" than their gasoline counterparts is a myth I've already dispelled so what exactly are you hoping to accomplish by continuing to display how poorly you understand physics?

quote:
An EV is not like one of your model aircraft and the correct terminology is Motor controller specifically so people like you won’t become confused. I posted this on the 4/16/2014 in this thread so it is what I have been saying all long.


EVs are virtually identical to model RC cars and planes, save for the Tesla using an AC motor while the models use DC motors and do not require an inverter.

You could call a speed controller a "motor controller" just like you could call a woman a "dame", but just like calling a woman a dame suggests you have no clue how to deal with women...referring to a speed controller as a "motor controller" suggests you have no clue about electric drive systems.

quote:
The advantage of full torque from zero is not having to have a clutch (or torque converter).The advantage is not having to have a clutch. It’s a mechanical simplification.


In terms of driving performance its really not an "advantage" in any way, shape or form. It's just a mechanical necessity, because there is no reason to idle an electric motor.

quote:
In the case of Tesla the range of the motor is so broad that it also doesn’t need a gearbox and can make do with a single reduction ratio. A further mechanical simplification. The net result of this is lower weight better reliability and reduced cost.


A direct drive is one of the perks of using an electric drive system, but I've demonstrated that it's a stretch to say that it is "better". As far as being more reliable? Maybe, maybe not. The motor itself is probably not going to break down but the complex electronics that make it run are prone to failure.

So you have a more reliable transmission but you introduce potentially thousands of potential failure points with each additional line of code and electronic component required to make the car work.

Net effect? No improvement over a modern gasoline car in this dept either.

quote:
So if torque is not consumed and power is consumed and power is torque x RPM then really it is just RPM that is being consumed?? LOL. You’re funny.


If an engine produces a constant 100 ft-lbs of torque and the no-load engine speed is 1,000 RPM, adding a load that reduces the RPM by 500 is equivalent to a 50% drop in power. Note that the input torque remains unchanged, hence it is not being "consumed".

(1,000 RPM x 100 ft-lbs) / 5252 = 19.04 HP (no-load)
(500 RPM x 100 ft-lbs) / 5252 = 9.52 HP (50% load)

It's funny that you cannot grasp this concept and yet feel compelled to continue replying. I almost feel like you're being wrong on purpose because you want me to educate you.

quote:
All that and you still haven’t said were torque in an idling engine is being transferred to.


Torque is transferred to anything that is connected to the output shaft of the engine. Why are you struggling with these kiddie concepts?

quote:
How does it feel Eric being bested by a “dim-witted buffoon”. Nothing in this world is free Eric not even cheap shots.


Really, or is this a segue into your comedy routine? LOL


"I mean, if you wanna break down someone's door, why don't you start with AT&T, for God sakes? They make your amazing phone unusable as a phone!" -- Jon Stewart on Apple and the iPhone














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