New Efficient Supercharger with Variable Drive for Downsized Gasoline Engines
22 September 2010
Rotrak, the new 50:50 joint-venture between traction drive specialist Torotrak plc and centrifugal supercharger company Rotrex AS, will present a highly efficient supercharger system in a paper at the 15th Supercharging Conference in Dresden on 24 September. The joint venture company combines a Rotrex supercharger with a Torotrak full-toroidal traction drive to produce a mechanical supercharger system that overcomes the problems inherent in conventional supercharger and turbocharger systems.
Turbo lag can become increasingly intrusive as engines get smaller. Superchargers are mechanically geared to enhance performance at either low or high engine speeds. The Rotrak solution overcomes this constraint by connecting the supercharger to the engine by a compact variable drive, allowing efficient operation across the whole engine speed range.
The need to reduce CO2 emissions is leading to downsized engines, heavily boosted by turbo- or supercharging. But while these engines easily reach high peak power and torque figures, they struggle to provide the required low-speed response. A fully integrated centrifugal compressor connected to the engine via a variable drive will achieve a unique combination of low- and high-speed performance with a highly cost-effective system.
—Torotrak engineering manager David Burtt, co-author of the paper
Gasoline engines are typically less expensive than diesels for the same application but have higher exhaust temperatures, making advanced turbocharging more difficult.
Independent analysis has estimated that the world market for pressure-charged gasoline engines will grow from 2.5 million today to 12 million by 2016. The emergence of a practical and cost-effective way to supercharge small gasoline engines could have significant market impact.
—David Burtt
Beside performance (hp) gain, what total efficiency gain (% or mpg) can be obtained with improved turbo? Smaller + lighter ICE, when coupled with lighter lower drag body, could provide better mpg.
Posted by: HarveyD | 22 September 2010 at 10:06 AM
This is like putting a CVT on a supercharger, kind of clever. We are trading hardware for fuel, so when fuel costs are $4000 per year and you can save $1000 per year on a more advanced model, people may consider it.
Posted by: SJC | 22 September 2010 at 10:38 AM
You'd think that with all the innovations documented by this site recently, someone would put them all together in one vehicle platform for a true quantum leap forward for the common ICE vehicle. Take an OPOC engine, add Fiat multi-air technology, a Rotrak supercharger, Transonic supercritical fuel injection, and add an Antonov TX-6 transmission...then you should have a platform for a vehicle that gets insanely good mileage.
Posted by: ejj | 22 September 2010 at 11:06 AM
I agree, one could go down the list of new developments and pick the best to make one heck of a car. Cost and price will always be an issue, but when trading costs with $4+ per gallon gas, the decisions become easier.
Posted by: SJC | 22 September 2010 at 11:33 AM
Problem is, with all the gas-saving devices and with oncoming PHEV's, etc. gasoline prices won't be $4 but may just hover around $2, enough to dampen any further incentive for higher fuel efficiency or petroleum-sparing technologies. OPEC may be tempted to drive gas down to below $2 in order to destroy existing investments in alternative fuel technologies, and to prevent any future of such.
Posted by: Roger Pham | 22 September 2010 at 01:49 PM
I think demand from the BRIC countries (especially China and India) will be enough to keep the oil market buoyant for quite some time.
Gasoline is $6-7 / US Gallon now in Europe (and has been for some time), and people get by, mainly by driving smaller cars, driving diesels and driving less.
There has been no apocalypse.
[Just Ford Fiestas and diesel Golfs] (etc)
Posted by: mahonj | 22 September 2010 at 03:20 PM
Before the Great Recession, demand was 87 million barrels per day and supply was 85 million barrels per day world wide. Once the world economy starts to come back we could see demand go to 100 million barrels per day world wide and supply no where near catching up.
Posted by: SJC | 22 September 2010 at 05:38 PM
Demand will always equal supply (plus inventory changes); the price will move until they match.
The exhaust-temperature issue isn't hard to handle by venting intake air into the exhaust to cool it (and EGT affects catalytic converters and filters, so it has to be managed regardless). Turbocharging eliminates the crankshaft load of supercharging, and can even feed exhaust energy back to the crankshaft (in diesels).
Posted by: Engineer-Poet | 23 September 2010 at 07:12 AM
Demand does not always equal supply, where do you get these "ideas"?
Posted by: SJC | 23 September 2010 at 08:57 AM
Roger. If that happens, it would be the ideal time to increase gas taxes by up to $2/gal.
The new Mercedes S250 is using some of the new ways to reduce fuel consumption as low as 41/mpg. If all known ways were used, including lither bodies with less drag, 60+/mpg would be possible.
Posted by: HarveyD | 23 September 2010 at 08:57 AM
Posted by: Engineer-Poet | 23 September 2010 at 05:43 PM
Demand may not go away, but substitution enters. If gasoline is $10 per gallon, some may use the bus, but their desire (demand) does not go away. If they get a raise in pay, they may buy gasoline again and drive, if they supply is available at the price they can afford. Either way, demand is still there.
There can be a world demand for oil that exceeds supply and we are about to see that happen. You can drive the price up and demand will appear to go away, but it does not. It is just the amount transacted at the given price that appears to be equilibrium. Demand can be thought of as the desire to purchase at a given price, but none is available at that price and the desire does not go away.
Posted by: SJC | 23 September 2010 at 09:33 PM
Another example is a cartel like OPEC. If world active demand wants 2 million barrels per day, but OPEC says no, then active demand exceeds available supply, because OPEC controls supply. It does not matter the bid price, the answer is NO.
Posted by: SJC | 23 September 2010 at 09:43 PM
Another example is demand destruction. If I buy an EV and like it, then I may not go back to gasoline even if the price goes down.
If gasoline is $5 per gallon, but supply is tight, there may be a line to get gasoline until the supply runs out. The people at the back of the line still demand gasoline at $5 per gallon, but there is no supply.
Raising the price to $10 per gallon will not bring more supply, the gasoline tanker truck does not arrive until next Tuesday. They are not likely to build more refineries nor drill more wells right away, so at $10 per gallon people buy EVs and you have demand destruction through substitution.
Just because on a given day a certain amount is sold at a given price does not say much about supply and demand. How much oil is in the pipeline? How many drivers have to drive farther in the future? Certainly potential demand in China and India is probably going to rise. It is not there yet, but people are contemplating that.
Posted by: SJC | 23 September 2010 at 10:53 PM
Demand destruction can be long-term. If people switch from 22-MPG vehicles to 40-MPG vehicles, their demand will almost certainly be slashed for the duration of their car loan. If they switch to the bus and scrap their car or allow it to fall into disrepair, their demand will be slashed until they can repair or replace it.
Thereby raising the price, pushing someone else out of the market for the limited and shrinking supply of petroleum. Demand will change to match the supply, unless and until the price falls so far that producers cut back or go bankrupt (which appears unlikely to happen, as it is not in the interest of anyone with the capability to do anything about it).That's not "demand" as used in economics. There has been a world desire for oil which is well beyond what's currently pumped; it's been that way since the price runup which began in 2005. The world would happily consume 90 million barrels per day if could be supplied for $20/bbl. Reality is over $70/bbl and demand around 84 million bbl/day at that price.
If you buy an EV (presumably trading in a car to buy it), you're going to be driving it until you can afford another vehicle. There is a certain amount of lock-in involved, and other inertia besides. US gasoline consumption took until the 1990's to recover to the pre-oil-shock level despite oil having been inexpensive for quite some time. People who bought Rabbits and Omnis and Chevettes didn't just go out and double their driving when gas prices fell by half; it took years for memory to fade and the SUV phenomenon to get going. It's taking equally long for the SUV phenomenon to die (a well-deserved and overdue death).
Meaning the commodity is underpriced. Political interference like "anti-gouging" laws always create rationing by unavailability instead of demand destruction by price.
No, but it may have cut demand to match the supply instead of under-pricing the commodity (which always leads to shortages). If the price went up to $10, people going out of the area would fill up before returning and might even bring some extra containers for additional fuel. If the price is artifiacally limited this doesn't happen until there are outright shortages.
Posted by: Engineer-Poet | 25 September 2010 at 09:07 PM
Under priced and overpriced are just convenient terms to make things fit they way you want them to. We will see gasoline go above $5 per gallon WITH shortages. I don't think you will have lots of people agreeing that gasoline over $5 per gallon is "under priced" except by some convenient definition in terms. Those are just economic circular explanations for something that should never have happened in the first place.
We need methanol to substitute for gasoline NOW. Not 5 years from now, we do not have that much time. I do not want to say years from now that I told you so. I want us to get ahead of the curve and head off a major problem before it occurs. Let's show ourselves how smart we really are and stop reacting to problems after they become huge. Let's get at the problem while it is still small, before it becomes too large to deal with.
Posted by: SJC | 26 September 2010 at 10:18 AM
There is also price elasticity of demand and supply. The price of oil quadrupled but the supply did not, the demand actually went up. With oil 4 time the price, the supply did not go up four fold and the demand did not go down by 3/4. The convenient explanation is that the oil was under priced, that is convenient but where is the equilibrium point? When most are priced out of the market and economies collapse?
We can not play experimental economic games trying to fit the square peg in the round hole. Too many people's lives and incomes are at stake. That is an after the fact experiment with too many lives on the line, that is wrong to do. After you turn this knob or that one and the collapse occurs, "oops" just does not cut it.
Quit trying to find convenient circular explanations to tell people that this is just the way it is, as if it is a natural process. Economies are man made, they do not follow natural physical laws. What goes up must come down is a simple attempt to explain complex situations and it does nothing to prevent the problems from occurring in the first place.
Posted by: SJC | 26 September 2010 at 10:39 AM
Around the peak a number of e.g. island nations were unable to pay for oil to run their electric grids and were at risk of going dark. That's demand destruction. A more controlled form of demand destruction is Aruba's new wind farm; oil is being displaced by renewables.
Posted by: Engineer-Poet | 26 September 2010 at 07:44 PM
"You don't do yourself any favors by showing how ignorant you are of elementary economics."
I have completed four semesters of economics, two lower division macro and micro and two upper division macro and micro with good grades. Would you care to share your academic achievements in economics?
Posted by: SJC | 27 September 2010 at 08:21 AM
There is education and then there is indoctrination. When you only take one semester of micro/macro economics you hear about how it is suppose to work, if all markets filled and cleared perfectly. If you go further with your education you learn that it actually does not work that way.
Posted by: SJC | 27 September 2010 at 10:07 AM
Posted by: Engineer-Poet | 27 September 2010 at 11:12 AM
I am done talking with you.
Posted by: SJC | 27 September 2010 at 11:28 AM
I could dismiss you with a snarky comment like "thank goodness for small favors", but you've really missed an opportunity here.
Despite your alleged superior education in economics, you haven't cited anything to back up your assertion about "over-pricing". I've linked to a definition of the market-clearing price, but if there are other relevant factors it would benefit others reading this thread to know what they are and how they work. Even if I would never believe you, you've failed to make your case to them.
If what you've got is the subject of established coursework, it's probably got a good write-up somewhere on the web. Link to it. It can't hurt.
Posted by: Engineer-Poet | 27 September 2010 at 08:23 PM
The problem is that most leaders and governments aren't too knowledgeable in Economics, and that's why we are in the big mess that we are in today!
One party believes in tax cut as a cure for all economic problems, and another party believes in more government spending and government programs as the panacea. All are intended as sound bites designed attract votes by the average, common people, with little comprehension of the economic process at hand, instead of a careful analysis and engineered plan by the engineers to coordinate all sectors and level of government with the private sectors.
Only the wealthy in the private sectors can have enough capital to create investments and businesses and jobs to ride out of the recession and the catastrophic budget deficit. Tax cuts for the rich or for small business won't help creating any jobs, if they don't know what to invest in that would give them a good return and a more certain future.
Posted by: Roger Pham | 27 September 2010 at 11:24 PM