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Doctorate in Mechanical Engineering, entreprenuer
Interests: diesel and gasoline engines, cars, aircraft, railroads, electric drives
Recent Activity
"The trick is to get from CO2 to CO" All it takes is energy as the reaction wants to go the other way. Basically, you can make anything if you have enough energy. However, I am really tired of hearing how we are going to make fuel out of surplus renewable electric power. We do not have surplus renewable electric nor do I believe that we ever will have. Maybe, we could use nuclear power especially if you can use the hear directly and skip the stage of generating electric power.
On and off between about 1990 and 2001, I worked on a 2-stroke opposed piston diesel engine that had the same crank, piston and connecting rod layout except that it now had 1 cylinder, 2 pistons, 4 connecting rods, 4 cranks, and a whole gear train to couple all the cranks together. I was not the designer but made an animated solid model of the assembly along with actual 1/3 scale rotating model of the first design which had a 1.5 liter displacement. The designer was Marius Paul from Engine Corporation of America (ECA). Unfortunately, their web site is no longer active. Later I was involved in making the cranks, connecting rods, and gears for a 3 liter per cylinder version. The engine was designed to run with an extremely high boost of about 150 psi. The 1.5 liter engine ran but had a number of problems with injectors, piston rings, etc. The 3 liter version was never completed. Anyway, I wonder some about the claim that "Neander invented a “space ball” design" as the engine I worked on had this design. Also, I know that FEV and Southwest Institute (SWI) had access to the ECA engine designs. Some of the original work was done with Detroit Diesel under a DARPA contract. The design does have the advantage that it does not have any piston side loads and it also has an advantage that they did not mention in that the compression take about 160 degrees of rotation while the expansion has about 200 degrees. However, it also has a lot of complexity that the single connecting rod, single crank engine does not have. I thought that the opposed piston opposed cylinder (OPOC) engine from EcoMotors with a single center crank was a clever solution to the multi-crank opposed piston engine with the gear train required to couple the cranks together. Interestingly, FEV was also involved with the OPOC engine.
This is probably better engineered but the 1957 Golden Hawk Studebaker (remember them?) offered a Paxton supercharger that had a variable speed drive. Is anything ever new? Of course Studebaker also offered electric vehicles about 110 years ago (1902-1912). Personally, I think that an electrically driven turbocharger is a better idea. At low power, you drive the compressor to produce more boost. At higher power, you pull electric power out of the turbo to control the boost and put the excess power back into the battery or drive other electric auxiliaries.
Thanks Herman More typing than I have time for but pretty much in line with my thinking. The VW vehicles look like a serious attempt to provide a range of electrified options along with other high efficiency vehicles.
Engineer-Poet: I would guess that more fuel is burned in local/regional trucking than long haul but use of LNG in long haul trucking is coming. UPS uses some LNG trucks between LA and Salt Lake. I believe that most interstate routes will have enough LNG refueling stations available by 2016 so that it would be possible to long haul on most routes using LNG.
Herman On a more serious note, I recently attended ConExpo (Construction Exposition) in Las Vegas mostly to look at Diesel engine emission technology and potential drive and part sources. John Deere had 2 diesel electric hybrid front-end loaders on display, one large (644K) and one very large (944K). Both used ultra-caps for energy storage. The 944K had individual electric motor drives while the 644K had a single electric drive motor with a more conventional drive train. Impressive machines. I was hoping that there would be one or more ultra-cap vendors with a display. Maybe next time.
I was at the recent ConExpo in Las Vegas (Construction equipment exposition) and talked to CAT, Deere, Volvo, Cummins, MTU, JCB about emission technology and efficiency. As best I could tell, running SCR which uses urea injection for NOX control instead of using cooled EGR allowed higher combustion temperature and therefore higher efficiency. Everyone seemed to have a slightly different story but everyone was claiming higher efficiency. The new Tier 4 final engines are quite clean and may even clean the air in certain polluted conditions.
Looks like it would be much more exciting to drive than most of Toyota's rather boring lineup.
Engineer_Poet Just to set the record straight, I was not blaming Americans for Japanese war atrocities. The Japanese committed horrendous atrocities during WW2 mostly to the Chinese but also the Koreans, Philippinos, etc. Anyway, I did get the number wrong, It was only 64 American airman that the Chinese helped escape. Out of 80 airmen, 3 died in crashes, 8 were captured (3 of those were executed and 1 was starved to death) and 5 landed in Vladivostok. For helping those 64 escape, the Japanese killed more Chinese that Hiroshima, Nagasaki, and the Tokyo firebombings combined. I was just trying to point out to Kelly that we are going to blame GM for questionable corporate activities that happened 80 years, we could look at some history that was only 70 years ago. Also, I am certainly no fan of Howard Zinn. I had to look him up in Wikipedia to make sure that I had the right person. It has been a long time ago (about 40 years) but I think that his son worked for the MIT Instrumentation Lab (Now called Draper Labs) when I worked there. Anyway, he hated his father and what his father stood for.
Kelly I was aware of GM's role in replacing trolley car with buses. I believe Goodyear also had a part in that. However that happened 80 years ago and it is unlikely that anyone that had anything to do with it is still alive. Also, the trolley and interurban system was already in trouble from increased use of automobiles. Maybe, you should blame Ford for mass producing low cost cars. Anyway, using your logic we could continue to punish the Japanese for WW2. Were you aware that the deadliest air raid in WW2 was not Hiroshima nor the Tokyo fire bombing but was the Doolittle raid? The bombing probably only killed a few Japanese but the Japanese killed over 250,000 Chinese because the Chinese helped 71 American airmen escape. That was only about 70 years ago. I think GM was largely responsible for the use of catalytic converters and the use of unleaded gasoline to reduce pollution. I remember Honda trying to push their CVCC technology back in the late 70's or early 80's as an alternative but fortunately GM prevailed and we have relatively clean burning engines and no longer have leaded gasoline. GM currently offers the Volt which is what I would consider the best of the PHEVs and offers an electric version of the Spark which has gotten good reviews. I would like to see them offer more electric cars but that may be in the works. I was happy to see them select Mary T. Barra as G.M.’s new chief executive as she has an engineering background and a father who had worked worked as a die maker at GM for 39 years. So she is both smart and knows the automotive business.
Kelly I have a hard time understanding your position. GM paid back the loans and the government has sold most if not all of their stock. GM is making a profit and in my opinion has a line up of very good vehicles and their engines are probably some of the best engineered engines available. There are several Japanese companies that would have been long gone had they not been propped up by the Japanese government including Nissan and Mazda. Nissan was in such bad shape that when it was bought by Renault, they brought in a Brazilian executive to try to straighten it out. Also, GM propped up Subaru (now part of Toyota), and Isuzu for a while. GM probably had some historical management and union problems but they were also carrying a large pension burden. I also think that some of their problems could have been prevented if the government had raised the tax on gasoline in a reasonable manner to encourage higher mileage cars instead of having the the CAFE system which encouraged the building of cheap fuel efficient cars while making a profit on luxury SUVs. They had actually started designing and building better and more fuel efficient cars before the collapse in 2008. Anyway, had GM gone under, they would have probably dragged the entire US auto industry under including the Japanese companies that are build cars in the US. I might note that I lost money as I had their stock. I have invested in them again and have a paper profit to show for it but not as much as I lost.
mahonj From "Colorado will also offer the segment’s only diesel engine in its second year – a proven Duramax 2.8L I-4 turbodiesel already offered in global markets."
Lad I was very surprised to see that BMW had offered a CVT with the Mini but they did for a few years for the first generation Mini. The current models have either a 6-speed manual or a 6-speed automatic. And, yes, slipping is the normal operation for a CVT. All traction type devices slip and in the realm in which they are designed to operate the slip is proportional to the torque transmitted in the same way that your tires are always slipping if they are transmitting any force to the road and the amount of slip depends on the amount of force. Roger Pham Nascar gets away without running a differential because the cars are always turning in one direction and never turning sharply during normal racing. Also, they tune the turning by running what they call stagger where the outside tires are a little larger than the inside tires. As the outside tires have more cornering load than the inside tires, the outside tires are also slipping more.
It may look complicated but I am sure that I would rather have this than a constantly slipping, constantly wearing CVT which I consider to be an out-dated idea. The only question that I would have is whether the lock-up torque converter is better than an dual clutch transmission. Maybe the lock-up torque converter is smoother and the dual clutch has slightly better performance. The dual clutch transmission seems to less complicated and has only 2 friction clutches.
Why drive some dull Prius when you could commute to work in the exciting new Porsche 919 hybrid?:)
I had a total of 3 different 3D printers in my university lab. The first was an early (1990 stereo lithography) and then 2 Fused Deposition Modelers (FDM). While the newer machines have improved, I was not very impressed with the capabilities of these machines. The ability to make weapons with these machines is very overstated. Basically, I always felt that the universities liked these machines as you could make something without any knowledge of real manufacturing techniques. If you want something other than a one-off models, these machines are mostly a waste of time. I also had a number of high quality CNC machine tools and had the ability to make real parts including transmission and engine parts.
Interesting but I doubt that it will fly. I think that it would be easier to use electric motor/generators to get the power into and out of the flywheel instead of a mechanical CVT drive.
I hope that this works out and is brought into production on a timely basis. If the traveling wave reactors come along later, they can presumably burn the waste. Any system that is not isolated in a completely remote area will be hocked to a grid and with 2 or more units, they would not need a backup systems as they will have a very high up-time or availability (almost certainly greater than 95%). However, it is common practice to have a backup power source so the controls keep working if the grid goes down but it would not be a disaster if the power is completely lost as there are no cooling pumps that must keep running to prevent a meltdown.
I have two major concerns: Where does the hydrogen come from. If it comes from steam reforming natural gas, it is probably better to just run a natural gas fired turbine (Brayton cycle) with a steam bottoming (Rankine) cycle. The second concern is with cold ironing which means turning off the main engine. Many of ships with a single very large diesel engine had engines that were started once and only turned off when they were either dry docked for rebuilding or were decommissioned. There was no on-board ability for the crew to restart the engine if it was stopped. Sounds strange but was true.
"We are also going to introduce new test cycles which will better reflect real driving conditions." Does this mean that they will no longer pretend that a 400 hp super car with a hybrid drive will get 60 mpg in real life driving conditions?
We were given a heads-up and a news release on this about 2 1/2 years ago. At the moment, we use a competitors gear drive with hydrostatic motors but I am planning on going to the ConExpo-Con/Agg trade show and this is something that I will want to see. I really believe that electric drives are the future but it will take a while to displace hydraulics. Anyway, it is another link to why electric drives are more efficient.
Peter_XX I am not scorning other solutions. As I said hydraulic hybrids may make sense for start stop applications with trash pickup trucks being the most obvious. But in general, hydraulics are not more efficient. As I said, I work as an engineer (and also part owner) of a start up building a specialized self-propelled agricultural harvester. The machine is part hydraulic and part servo electric. We use hydraulics for some functions as they are more cost effective but they are not more efficient. We just changed one function from hydraulic to electric. The electric drive cost more but the performance was better. In the future, we anticipate changing more functions to electric and would like to go to electric traction drives but we currently use hydrostatic drives with a variable displacement pump and 2 speed motors. Why? Because the hydrostatic drives are less expensive but they are not more efficient. It is also not where most of the power s being used during normal operations. We do use electric drives for some of the high power consumption functions and it makes a major difference in fuel consumption. The Peugeot air/hydraulic hybrids will be more efficient than non-hybrids but I would not expect them to be more efficient than electric hybrids. However, the air/hydraulic system may be less expensive.
I believe that a hydraulic hybrid may be more cost effective than an electric hybrid for some stop and go applications. A trash pickup truck is an obvious example where the truck accelerates to the next stop which may be only 30 m away and then brakes. These trucks also have other hydraulic functions so a hydraulic hybrid makes sense. However, while it may be more cost effective in the current market, it is not more thermal dynamically efficient. We had a meeting last week with some sales engineers from Parker Hannifin, Parker is big in hydraulics and builds some of the hydraulic trash truck hybrid systems. However, they are working on electric traction drives which is what they were trying to sell us. They told us that they are working on electric hybrids for trash trucks because of greater efficiency. There are a number of problems with the efficiency of hydraulic systems. Most hydraulic accumulator are gas over hydraulic. When you compress a gas, it heats up. If any of this heat is lost, it is an efficiency loss. A bigger problem is flow loss especially thru flow control valves (throttling loss). Modern digital Pulse Width Modulated (PWM) electric controls do not have this problem as the power is either full on or full off and do hot have the equivalent of a throttling loss. Also, in general, electric motors and alternators are more efficient than hydraulic motors and pumps. Now, why is Peugeot building their air over hydraulic system? Maybe they think that it is less expensive and they will have a cost niche. Maybe, they just want to be different.
Peter_XX Who said (besides you) that electric drives are more efficient than hydraulic? John Deere Caterpillar "Compared to the Caterpillar D7R Series II, the D7E is projected to deliver 25 percent more material moved per gallon of fuel." Comments from Caterpillar on the Cat 6120B H FS "Cut your fuel cost per ton by at least 25% compared to other shovel options – without sacrificing productivity – with our diesel-electric hybrid technology." See I work for a start up that is using electric servo drives on a specialized piece of agricultural equipment. Essentially, an electric gentry robot. Anyway, our fuel consumption is about half that of our competitors who use hydraulic drives. We will be converting more of the machine to electric. We recently had a sales presentation from Parker on the possible use of electric traction drives. Parker build both hydraulic and electric drives but I think that the handwriting is on the wall for the future of hydraulics -- it is on the way out for many applications. Also, if hydraulics were more efficient we would have diesel hydraulic locomotives instead of diesel electric locomotives and this idea was given a serious try back in 50's or 60's.
I hope that this comes to fruition. Of all of the low carbon energy solutions that I have seen, this is the one that seems to make the most sense. High energy density with low land use and low waste. I believe that you can also burn up the existing nuclear waste with this type of reactor.