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Re: Another great idea from the government a new IC engine - 14 years ago
Harry- Speaking as an interested stockholder, is anyone close to commercially producing one of these yet? Tomby TH - SteamStuff
Re: Parts -- tubes and benders - 14 years ago
Rolly- Normally you only get mill tensile properties on alloy or high strength low alloy steel. Chemistries are normal, these days most everyone is pretty consistent about them. Make sure the sulfur is below .010%. Some of the Chinese and Russian stuff is a little shaky. Your process of heating the inside is a good one if you go to red heat, since the gain in wall thickness will probablyby TH - SteamStuff
Re: Turbulator's - 14 years ago
Jeremy- You really don't want to heat those pipes to red heat, unless you are making them out of 304 stainless. Carbon steel loses strength above 1340F, and it will creep, i.e. blow up like a balloon, over time below that. Alloying can raise the usable temp, but it costs more. 304 will take red heat, and nickel alloys like Inconel will go as high as you want, but unless you won the Lottery,by TH - SteamStuff
Re: Another great idea from the government a new IC engine - 14 years ago
Actually, this might be a good time to try for some funding. Most of the folks in Transportation and Energy that were burned by Lear and the others are retired by now, and as this election proves, most people have short memories. As long as it's framed as a green idea (burning biofuels?) it could work. Makes the burner and emissions work a bigger problem, but that's what government grants areby TH - SteamStuff
Another great idea from the government a new IC engine - 14 years ago
This is a news item from Argonne National labs on a burn-nearly-anything engine. Just think how much easier this would be for a boiler!! I guess steam isn't complicated enough for the government to be interested. http://www.anl.gov/Media_Center/News/2008/ES080905.pdfby TH - SteamStuff
Re: You guys have to take a look at this car. - 14 years ago
Bottom line, a car maker has to be able to make an engine, a trans and a drive train and drop it into a chassis and have the whole package cost somewhere in the thousands, not tens of thousands, AND comply with all the smart and/or idiotic rules the various federal, Canadian and state agencies come up with, AND keep the company lawyers and ambulance chasers off their collective back. This is notby TH - SteamStuff
Re: You guys have to take a look at this car. - 14 years ago
Caleb, Peter, Ok, where to start? First, the engineers are not in charge, haven't been since Hank the Deuce kicked off. Congress, the liability lawyers and the bean counters dictate what gets built. Us grunts just have to live in that world. Any good ambulance chaser would crucify GM if they built a car based on a aircraft style tube frame. And if you think you can build a safer car by maby TH - SteamStuff
Re: You guys have to take a look at this car. - 14 years ago
I think the Rotax engines are not all they are cracked up to be. Looking at the retail price of the largest one I could find, which is still pretty puny for a four passenger vehicle, they seem kind of pricy for an auto application. Also, an engine that is intended for occasional use like a snowmobile or airplane has different design needs than a vehicle. The typical powerplant coming out of Deby TH - SteamStuff
Re: You guys have to take a look at this car. - 14 years ago
Peter, Unfortunately you are looking at half the picture. I sat through a fascinating session at last year's SAE congress about using high strength steel to reduce car weight. One of the talks was about the reasons we have to change the way we make cars, by looking at the changes over a decade of the Rabbit. The original Rabbit weighed 1700#, got over 40 MPG and was a deathtrap. A decade lby TH - SteamStuff
Re: You guys have to take a look at this car. - 14 years ago
Ken You're right about the continuing improvements in steel development to reduce weight. I've been working on some motor mounts recently, and by changing the steel to an advanced high strength grade I reduced the thickness used by 35% with no safety issues. This stuff has actually better fatigue properties than the grade used before. Other parts can be even thinner, depending on the endby TH - SteamStuff
Re: Compressive Steam Condensation - 14 years ago
Yes, this topic has wandered a bit. Nukes would be needed to support plug-in hybrids and straight electrics. I've been fascinated by the pundits and greenies pushing this alternative and at the same time fighting the powerplants to support it. Solar and wind are a joke for the amount of power needed. I have seen Boone's weather vanes on trucks on I-20 regularly, and it seems like a lot of efby TH - SteamStuff
Re: EFFICENCY - 15 years ago
The process GM is using would not use the boiler as an electrode. Like Jeremy said, that would be begging for corrosion problems. This is using the differential between waste heat and ambient temp to drive large thermocouples and make a few watts. If GM can make a reasonably priced unit I for one would have no qualms about stealing the idea. No moving parts (maybe a fan for the heat sink), aby TH - SteamStuff
Re: EFFICENCY - 15 years ago
The idea is to run the power into a battery or other accumulator. It's DC to begin with, so it would be easy to use as a charging source. It all depends on how well it works with the temperature range available. Once GM puts it on a car info should be available.by TH - SteamStuff
Re: EFFICENCY - 15 years ago
One other thought, even with a very efficient boiler setup there will still be a significant amount of waste heat in the exhaust. Since that type of heat is what this system was intended for, that could be a good spot for it. It's not continuous, but nothing is on a steam car. That's why they invented batteries. Is that what you are doing with your boiler, Bill?by TH - SteamStuff
Re: EFFICENCY - 15 years ago
Hi Bill This could eliminate the need for an alternator, more of an exchange of stuff instead of an add-on. Fewer pulleys and belts, for one thing. This will reduce the load on the condenser, so you can shrink it as well. Heat sinks are no big deal anymore, anyone dealing with high-power semiconductors can whip up a heat sink big enough to handle this. Also, with no moving parts this shouby TH - SteamStuff
Re: Bower and Bell engine - 15 years ago
Hi Brian Hope the tests are going well. Going back to my January questions, have you any performance data yet? Tomby TH - SteamStuff
Re: EFFICENCY - 15 years ago
You are missing my point. Fins can significantly increase heat dissipation while keeping cost and weight under control, if you use a good conductor for the design. Fins are a lot cheaper than tubes, and can be a lot thinner. Show me any production vehicle that doesn't use fins in the radiator. Is the idea to design for an expensive hobby, or a practical car? Out of curiosity, have any of yby TH - SteamStuff
Re: EFFICENCY - 15 years ago
Rolly This depends on the design. There is still an effect, and if you use fins there's a BIG effect. A finned design will cost a lot less to build for materials and have fewer joints to leak. More to the point, I don't want a one-off design built by a watchmaker that takes a month to make one radiator. A good design can be made by a simple series of steps. Form, anneal, form anneal, again aby TH - SteamStuff
Re: EFFICENCY - 15 years ago
Some points to ponder... Aluminum has half the thermal conductivity of copper, but copper is 3.3 times denser, so for the same weight you should get almost double the heat transfer. The tradeoff is formability. Copper is great, but aluminum... Pure aluminum is good, but has no strength; alloy Al is strong but has lousy forming. That's one reason why they gave up on aluminum body panels for higby TH - SteamStuff
Re: EFFICENCY - 15 years ago
Caleb: Annealed copper is very soft, around 15ksi (100 mPa) yield strength. It hardens up nicely as you form it, but the thicknesses you mentioned will be very weak. Are you planning to use this as fin stock, or as part of the tube structure? In my youth I worked with tin plate steel down to .006", and with a nick in it you can tear that stuff with your bare hands. It's possible to makeby TH - SteamStuff
Re: EFFICENCY - 15 years ago
I looked at the Mesabi site, and I must admit the quick-change setup is slick. This system is designed to work under positive pressure, though. How well will it seal with negative pressure? Tomby TH - SteamStuff
Re: EFFICENCY - 15 years ago
Wow, where to start... Hundreds of 1/4" tubes means hundreds of flared ends and joints, and hundreds of chances for leaks. If you have access to a brazing oven there are ways to gang solder this, but for a prototype that's a lot of work. Got a spare month or so? Oval tubes with convolutions to increase surface area seem a lot more practical. The larger cross-section will prevent pluby TH - SteamStuff
Re: Allen Uniflow Book - 15 years ago
How many man hours will take to scan it? Tomby TH - SteamStuff
Re: EFFICENCY - 15 years ago
Bill: forming aluminum depends a lot on what grade you are using. We make truck steps for Peterbuilt from 5052, and if you slightly overform it throw it away. It's full of microcracks. Other alloys can be more forgiving, but you can overage some alloys at saturated steam temps, so the strength can drop significantly. Copper can be real easy to form, we make dome shaped parts 3" diameterby TH - SteamStuff
Re: EFFICENCY - 15 years ago
Caleb That extra 45 gallons is about the same as my girlfriend and me in the back seat (she's small, I'm not). A moderate amount of weight but may be a reasonable fix. I'm still interested in feedback about an auxiliary engine for accessories. One other thought, on the topic of large tanks: since one main problem with frequent refills is mineral accumulation, what if you put in a secoby TH - SteamStuff
Re: EFFICENCY - 15 years ago
I think sometimes we box ourselves in by overdesigning for worst cases. Making decisions based on having the capacity of an F-350 crew cab dually hauling an Airstream trailer up Pike's Peak is a neat exercise, but might be overkill. One thought buzzing in my head is a second, small engine that would run auxiliaries. Design for a small constant-speed maximum efficiency unit to power the altby TH - SteamStuff
Re: EFFICENCY - 15 years ago
Maybe I'm a little slow. but I was under the impression that one of the benefits of steam was that when the car was sitting there was no steam in use. Doesn't that imply that at very low speeds there is very little to condense? If you assume a 50% speed reduction of airflow through the unit compared to car speed. that 8.5 MPH needed translates to 17 MPH car speed. That's without fan assist,BTWby TH - SteamStuff
Re: EFFICENCY - 15 years ago
Having a little experience with forming metal (about 30 years or so) I think the dimpled tubes could be made economically if there was enough volume to justify the investment. Metal tube is made by roll forming a slit width into an o-cross section, then heating the edges and mashing them together. Round, oval, hexagonal, just a matter of how many rolls you need to put in place. Done all the tiby TH - SteamStuff
Re: EFFICENCY - 15 years ago
One fundamental problem with biofuel on the ethanol side is transportation. SOP for petroleum movement is pipelines with distribution centers to minimize cost. Gas, kerosene, etc. are pumped through the line, followed by a slug of water to clean the pipe for the next grade. Can't do that with ethanol, it mixes with water and will degrade the product. Truck or rail are much more expensive. Thiby TH - SteamStuff