Octave 3 under windows is a very usable system. I prefer Scilab, in many ways to both Octave and Matlab, but at work I have Matlab and it is easier to switch between Octave and Matlab than Scilab and Matlab.
I've worked on the same car for 17 years. In that time the/base/ model has gone from 130 kW to 187 kW, manual to auto, heater to full automatic climate control, 6 airbags, ?crash to five stars, 16 inch wheels not 14 inch wheels, electric windows, electric seats, AmFM radio with two speakers to a CD with 6 speakers, and a vast reduction in emissions,ABS, IRS instead of live rear axle, etc etc. Fuel consumption has improved slightly.
Sure, we could have put all our engineering effort into reducing fuel usage, nobody rational would buy the thing.
Maybe, maybe not. See if you can follow this line of argument. If the device increases the efficiency by 5 to 20% then a current engine must lose 5-20%, compared with some ideal state. The only two things the device can do is change the combustion efficiency (that is, the proportion of the fuel that is burnt), or the combustion timing (that is, when the fuel burns).
In a typical diesel engine >99% of the fuel is burned (that is , HC emissions are very low), partly because a typical modern diesel doesn't run rich even at full torque. So it ain't the combustion efficiency.
The timing one is, I would admit, a bit of a possibility, but, if you look at the incremental bsfc at a constant speed, that is, how much the fuel consumption per unit power changes as you increase the power, it doesn't really indicate to me that there is any drop off in efficiency as the fuelling increases, and the burning takes longer. So, it seems to me that the burning process is fast enough.
As others have pointed out, rather than driving around in some crappy old car the proper experiment (you know, the scientific method) that any universty with an engineering department could do is to map the BSFC for the engine over its operating range.
Is the driving around experiment good science if he doesn't know his error limits?
So, 20%=snake oil. 5% - well, I don't believe it but just maybe.
The efficiency advantage of an 'over expanded' engine decreases as the compression ratio increases. Above 14:1 the difference is very small. So, given the power disadvantage of the Atkinson cycle, and of diesels, it seems unlikely that anyone would really bother with overexpanding a diesel engine.
It's not exactly a valid experiment, but on my mountain bike my lardy ass can keep up with a stringbean on a recumbent bike, on hill climbs. I used to go on week long cycling holidays with 1000-3000 other riders and was able to perform all sorts of experiments like this. I'm talking about the traditional 2F1R recumbents, I haven't seen enough of the others (such as short wheelbase 2 wheel recumbents) to try. Fantastic machines, great fun to ride on the flat, but Teh Suck up hills.
By hills I mean 10-20 minutes or so at 12-18kph. I believe on the Tour de France these are known as false hills,according to Phil Legett, who seems to think that anything less than 8% is practically downhill.
I've often argued that oil is too valuable to use as a fuel (generally), but really, why is it any harder to use coal or algae, or whtever as a plastic feedstock?
Mm. I think what amuses us is that Michigan's revolting arrogance has had so little result in the WSC. I think you did manage to beat us once, 18 years ago.
Shame really, most of the kids on the Michigan team seem OK, individually, but en masse, pass the sick bag, Alice.
When driving in traffic it is up to the following car to maintain a safe distance from the car in front.
Because the addition of affordable quantities of solar power to a conventional car would make virtually no difference to the running cost. Even if you used say 3 square yards of the best cells available you would be lucky to get 2 kWh per day, roughly equivalent to half a gallon of fuel. But, that array would cost you about $300000. If you send me $300000 I will send you $2 every day in return.
It typically takes me 10 minutes to store the state of where I was, 5 minutes to answer the 'quicky', and then 45 minutes to get back to where I was, in terms of train of thought.
Good call. I score some bullshit number on IQ tests (185, once, in a real one). I am smarter than the average bear, for sure, but... that bright and glinty ability to whizz through IQ tests is only vaguely related to my analytical success which is down to grim concentration and long, hard, thought. Quite why the shithead management persist in putting us in pods of cubicles so that I get the 'benefit' of background chatter is beyond me. Fortunately my sound cancelling headphones deal with that, albeit at the expense of giving me something more interesting than spreadsheets to entertain myself with.
Clue for fuckwit managers- if your staff are interested in music and are truly listening to the Brandenburg concertoes, then they are not paying much attention to the screen in front of them. Bach is a mind sucking alien.
Well I guess that is a choice you make. Why not use that time to learn some skills and get a decent paying job? I don't actually work as many hours as I can, I find that 37 hours at work, 2 hours doing my shares and up to 10 hours a week consulting is quite enough.
It seems odd to castigate me for putting a value on my time and then in your last sentence confirm that that is exactly what you do!
My time is $60 per hour, according to my payslip. If I do after hours consultancies I charge $150 ph. Exactly how fucking cheap would these groceries have to be, for the same quality?
I loathe shopping. The idea of driving further to do it is just insane.
My W95 machine would, just, run a GUI under Linux (RedHat) in 1997. It was amazingly slow. At the time I was told it needed far more RAM. As a W95 machine it was fine and would run games like Total Annihalation.
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You talk bollocks.
One-off conversions are signed off by engineers.
Gosh, that sounds very technical.
It is however a load of crap.
Modern EECs are designed to work correctly down to 8V, and will be as happy as Larry above 11V.
Could you enumerate those 10 reasons?
I'm not a huge fan of GM, but, so far as I can tell, the Volt is an interesting rethink on the (very) old Prius type strategy.
Octave 3 under windows is a very usable system. I prefer Scilab, in many ways to both Octave and Matlab, but at work I have Matlab and it is easier to switch between Octave and Matlab than Scilab and Matlab.
Good question.
I've worked on the same car for 17 years. In that time the /base/ model has gone from 130 kW to 187 kW, manual to auto, heater to full automatic climate control, 6 airbags, ?crash to five stars, 16 inch wheels not 14 inch wheels, electric windows, electric seats, AmFM radio with two speakers to a CD with 6 speakers, and a vast reduction in emissions,ABS, IRS instead of live rear axle, etc etc. Fuel consumption has improved slightly.
Sure, we could have put all our engineering effort into reducing fuel usage, nobody rational would buy the thing.
Maybe, maybe not. See if you can follow this line of argument. If the device increases the efficiency by 5 to 20% then a current engine must lose 5-20%, compared with some ideal state. The only two things the device can do is change the combustion efficiency (that is, the proportion of the fuel that is burnt), or the combustion timing (that is, when the fuel burns).
In a typical diesel engine >99% of the fuel is burned (that is , HC emissions are very low), partly because a typical modern diesel doesn't run rich even at full torque. So it ain't the combustion efficiency.
The timing one is, I would admit, a bit of a possibility, but, if you look at the incremental bsfc at a constant speed, that is, how much the fuel consumption per unit power changes as you increase the power, it doesn't really indicate to me that there is any drop off in efficiency as the fuelling increases, and the burning takes longer. So, it seems to me that the burning process is fast enough.
As others have pointed out, rather than driving around in some crappy old car the proper experiment (you know, the scientific method) that any universty with an engineering department could do is to map the BSFC for the engine over its operating range.
Is the driving around experiment good science if he doesn't know his error limits?
So, 20%=snake oil. 5% - well, I don't believe it but just maybe.
As I said, data taken from Heywood.
Why do you like MacPherson struts? And what is so great about their IRS?
It's all well executed stuff that works, but frankly so it should, on the Ultimate Driving Machine.
That's a pretty whiny article, and is wrong in the most crucial technical detail.
Here's the sfc for a Prius at 100% throttle, in g/kWh, sorry about the formatting
speed rpm ---->
500 1000 1500 2000 2500 3000 3500 4000 4500
|
727 396 323 270 243 237 235 236 246
I hope you see why whiny treehugger was talking crap.
The efficiency advantage of an 'over expanded' engine decreases as the compression ratio increases. Above 14:1 the difference is very small. So, given the power disadvantage of the Atkinson cycle, and of diesels, it seems unlikely that anyone would really bother with overexpanding a diesel engine.
Terminology and data taken from Heywood.
" It took $4/gallon gasoline before American companies decided to 'import' their small euro models."
I think you've misspelt
" It took $4/gallon gasoline before American consumers decided to 'buy' small euro models."
It's not exactly a valid experiment, but on my mountain bike my lardy ass can keep up with a stringbean on a recumbent bike, on hill climbs. I used to go on week long cycling holidays with 1000-3000 other riders and was able to perform all sorts of experiments like this. I'm talking about the traditional 2F1R recumbents, I haven't seen enough of the others (such as short wheelbase 2 wheel recumbents) to try. Fantastic machines, great fun to ride on the flat, but Teh Suck up hills.
By hills I mean 10-20 minutes or so at 12-18kph. I believe on the Tour de France these are known as false hills ,according to Phil Legett, who seems to think that anything less than 8% is practically downhill.
I've often argued that oil is too valuable to use as a fuel (generally), but really, why is it any harder to use coal or algae, or whtever as a plastic feedstock?
Can't prove a negative but zero accidents in 25 years of driving, including a lot of high speed work.
Mm. I think what amuses us is that Michigan's revolting arrogance has had so little result in the WSC. I think you did manage to beat us once, 18 years ago.
Shame really, most of the kids on the Michigan team seem OK, individually, but en masse, pass the sick bag, Alice.
When driving in traffic it is up to the following car to maintain a safe distance from the car in front.
Because the addition of affordable quantities of solar power to a conventional car would make virtually no difference to the running cost. Even if you used say 3 square yards of the best cells available you would be lucky to get 2 kWh per day, roughly equivalent to half a gallon of fuel. But, that array would cost you about $300000. If you send me $300000 I will send you $2 every day in return.
ah, good someone has quantified it. My opinion is that it is longer than 15 minutes, but that is the right ballpark
It typically takes me 10 minutes to store the state of where I was, 5 minutes to answer the 'quicky', and then 45 minutes to get back to where I was, in terms of train of thought.
That adds up to an hour.
So I switch me email off and turn my phone down.
Sorry guys...
Good call. I score some bullshit number on IQ tests (185, once, in a real one). I am smarter than the average bear, for sure, but... that bright and glinty ability to whizz through IQ tests is only vaguely related to my analytical success which is down to grim concentration and long, hard, thought. Quite why the shithead management persist in putting us in pods of cubicles so that I get the 'benefit' of background chatter is beyond me. Fortunately my sound cancelling headphones deal with that, albeit at the expense of giving me something more interesting than spreadsheets to entertain myself with.
Clue for fuckwit managers- if your staff are interested in music and are truly listening to the Brandenburg concertoes, then they are not paying much attention to the screen in front of them. Bach is a mind sucking alien.
I would but the mod category "comically stupid" seems to have gone missing in action
Well I guess that is a choice you make. Why not use that time to learn some skills and get a decent paying job? I don't actually work as many hours as I can, I find that 37 hours at work, 2 hours doing my shares and up to 10 hours a week consulting is quite enough.
It seems odd to castigate me for putting a value on my time and then in your last sentence confirm that that is exactly what you do!
My time is $60 per hour, according to my payslip. If I do after hours consultancies I charge $150 ph. Exactly how fucking cheap would these groceries have to be, for the same quality?
I loathe shopping. The idea of driving further to do it is just insane.
Sorry, not in my experience.
My W95 machine would, just, run a GUI under Linux (RedHat) in 1997. It was amazingly slow. At the time I was told it needed far more RAM. As a W95 machine it was fine and would run games like Total Annihalation.
Gosh, FUD.
The current equivalent of my laptop costs 498 Oz dollars. Add 200 bucks of memory.
It runs
FEA software
MS Office
MSC ADAMS
Lots of games
Solidworks
In fact I struggle to think of any serious software it won't run. Maybe some games, I suppose.
And, since I have VMware installed it runs Linux software as a client ( is that the right word?) as well.
FUD FUD FUD FUD FUD
My engineering (real engineering that can kill people) job takes me one hour to walk to, 15 minutes on my pushbike, or 7 minutes by car.
So, in the other 3.5 hours I have over you, I could either do consultancy work, read books, go sailing, or get drunk in the pub with my friends.
Good luck with the lifestyle.