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Doctorate in Mechanical Engineering, entreprenuer
Interests: diesel and gasoline engines, cars, aircraft, railroads, electric drives
Recent Activity
I believe that the Class 8 Heavy Haul would be somewhat better using LNG with diesel pilot for ignition as being marketed by Westport Innovations. This allows the engine to run as a true compression ignition diesel while primarily running on natural gas. The article does note that this type engine was not considered as there was not sufficient data.
Yup, hard to make predictions especially about the future. Very difficult when the future is 10 years out and you do not know what the breakthroughs will be. Maybe Tesla will have taken over the automotive world or maybe they will have gone bankrupt and be all but forgotten.
GM either has or will have a more random deactivation scheme that is basically load following. For a V8, it could fire 5 cylinders one revolution, then 4 or maybe even 3 and all cylinders would see an equal loading.
Water injection was commonly used during WWII for turbocharged radial aircraft engines during takeoff. (high power and low altitude) It was also used in the 1962-63 Turbocharged Oldsmobile F-85.
This thing sets a new standard for UGLY. It would be more like a rain drop if was running in reverse, except that a raindrop only has that shape as it drips off of something. Once it is free, the surface tension pulls it into a sphere. You can get the same effect of the so called bone structure by separating 2 skins with either foam or honeycomb material which is how most race cars and contemporary aircraft are made. If I was grading it, I would give it a D at best.
Lad Ford is not shipping jobs out the US to Mexico. The US auto companies have had a long standing agreement with both Canada and Mexico where no duties are paid either way as long as the dollar value being shipped both ways balances. Ford builds engines in Mexico which are shipped to the US and US made Ford Taurus (for example) or US made Ford Escapes are shipped to Mexico. What this accomplishes is that it allows the smaller Mexican and Canadian markets to have a complete lineup of Ford (or GM) vehicles. Unfortunately, I do not have a solution for the low interests rates on savings.
I think that it is a beautifully designed car and it is probably really pleasant to drive but I still think that the price differential over the Chevy Volt is way too much. Maybe, I could justify a $10,000 price differential but the differential is apparently more like $30,000 (2016 ELR price and 2015 Volt price?).
This car looks really nice and the coefficient of drag of 0.26 is impressive but it will not get 60 mpg. With the diesel, it might get a real 45 mpg and with the 3 liter turbo-charged gasoline, it might get high 20's with careful driving. The numbers that come out of the European and Japanese driving cycles are very much inflated.
The Malibu is a larger vehicle than the Volt which more the size of the Chevrolet Cruze. Anyway, I am glad that GM is bringing out a reasonable strong hybrid onto the market. With the Volt, the Bolt (which needs a better name in my opinion) and the Hybrid Malibu, GM will have a reasonable electric lineup to build on.
Probably the only practical way to make hydrogen without generating CO2 is high temperature electrolysis using nuclear power and even then it is questionable. We will never have enough "renewable" electric power to waste on electrolysis. The power density is just not there. A good estimate for average electric capacity is 1 w/m2 for wind energy and about 25 w/m2 for solar photovoltaic for a reasonable sunny location. I did a calculation for the land area just to supply the current electric requirements for the US using 1.5 Mw wind turbines with the recommended spacing and ended up with twice the area of Wyoming.
Carnegie Mellon drove an automated car from Pittsburgh to San Diego(?) sometime before the DARPA Grand Challenges. So it was at least 12 years ago. They probably needed to take over for fueling and stopping but I believe all of the actual highway driving was done fully automated. Also, they did not announce their intentions to do this before hand.
If I understand this correctly, you could lower the smog level or at least the ozone level just by driving thru polluted air.
With a 50 mile range, the GM Volt looks like the clear winner among the PHEV vehicles announced today -- the Hyundai Sonata with 22 miles, the Mercedes-Benz C 350 PLUG-IN HYBRID with 19 miles, and the Volkswagen Cross Coupe GTE with 20 miles. For a point of reference, I live in the wide open west (Salt Lake City area) with a daily commute of 44 miles on the rare days that I only drive from home to work.
D You are probably confusing vehicles (maybe with the Plug-in Prius which has a limited electric power output). The current Volt has always run in full electric mode as long as the battery has sufficient charge and has a listed top speed of 100 mph with the notation in parentheses -- Test Track so it may be computer limited to 85 or so. Anyway, it has 149 hp in electric mode. With the battery depleted, it still mostly runs electrically with the ICE driving a generator. At higher speeds, the ICE clutches in to drive the wheels to optimize fuel efficiency.
Peterww GM has lots of dynomometers and exhaustively tests all of the engines. What the estimated torque figure means is that they have not finalized all of their ignition and fuel mapping. With computer controlled ignition and injectors, there are many possible parameters to set to optimize emissions, power, response, and economy. One of the more amazing videos of GM engine testing is on the following video which show a fully gimballed dynomometer running a race simulation on a Corvette engine with the engine tipping for cornering, acceleration, and braking loads.
I really doubt that there patents are worth much other than the goodwill that Toyota hopes to gain. All of the car companies have been working on this for a long time and probably have more patents than they know what to do with. Fuel cells have been worked on since 1838 (177 years)! Talk about a technology that has taken a long time to become commercially available. In 1959, Allis Chambers (remember them?) introduced a fuel cell tractor.
Maybe they have decided that the best use of their fuel cell patents is good publicity.
Out of curiosity, I wonder how much the CO2 is increased when you burn peat to make electricity.
This is not exactly new. The Chevrolet (GM) Corvette has had transverse glass leaf spring for both the front and rear for quite a while -- 15+ years?
Lad, Most 2-stroke diesels are relatively clean running while most 2-stroke gasoline engines are quite dirty. 2-stroke engines require a positive manifold pressure to work. The small 2-stroke gasoline engines use the back side of the piston to pump the fuel-air mixture into the combustion chamber and therefore need to have oil in the mixture as the bearings, etc are exposed to the fuel-air mixture. 2-stroke diesels have superchargers and/or turbochargers to supply the positive manifold pressure and the fuel is directly injected into the combustion chamber in a normal diesel manner. It is possible to build a clean burning 2-stroke gasoline engine but it requires a super-charger, direction injection and probably either poppet exhaust valves or opposed pistons. Most 2-stroke diesels either use poppet exhaust valves or opposed pistons and are referred to as uniflow scavenged engines. Most 2-stroke gasoline engines are loop-scavenged.
I am guessing that it is a student project. It looks like something that my students would build and needs some packaging and professional design work. However, if the cost is comparable to a pure battery vehicle, it is probably a good thing but you do not typically need as much range in this type of vehicle.
This only works when the engine is running and producing heat and even then you only get 1 KW from a engine that produces 450 KW (600 hp). A solid oxide fuel cell would probably be a better device as you would use it instead of running the engine when you only need electric power. Also, a modified turbo charger that includes a motor generator would generate more power using excess exhaust heat. But having said that, 1.5 million for some applied research may be a reasonable deal.
Davemart Theoretical efficiency is the efficiency you would get taking the ideal compression, ideal combustion, ideal expansion without any losses. Indicated efficiency is the efficiency that you would get taking the actual engine pressures so it would include compression, combustion, and expansion losses but would not include mechanical losses. What really matters is brake efficiency as this is the power measured with a dynamometer and compared with the theoretical power of the fuel consumed. However it is good to know something about theoretical efficiency and the indicated efficiency as that gives you some idea where your losses are occurring and what to strive for. You will not do better than Carnot efficiency but you can certainly get more than 45% as modern uniflow 2-stroke ship diesels get better than 50%. One of the potential problems with the proposed engine is that they say nothing about pollution controls. If they have high pressure, high temperature combustion which leads to higher efficiency, it also leads to high NOX generation. However, it may still be better than the 2-stroke SI engines running a mixture of gas and oil used for leaf blowers, etc. Those should be banned.
This is probably a very nice car and will get good mileage but as mahonj points out it will not get 57 mpg in the real world. The US (EPA), Europe, and Japan need to get together and have consistent mileage testing that is somehow close to what people could expect to get with normal driving. The US (EPA) ratings are probably much better than either the Japanese or European ratings but they have also had problems (and some deliberate cheating).