BMW ICE Steam Hybrid
Finally, someone finds a practical way to use the wasted ICE heat: http://www.gizmag.com/go/4936/ The concept uses energy from the exhaust gasses of the traditional Internal Combustion Engine (ICE) to power a steam engine which also contributes power to the automobile ? an overall 15 per cent improvement for the combined drive system. ___ Try the New Netscape Mail Today! Virtually Spam-Free | More Storage | Import Your Contact List http://mail.netscape.com
Re: BMW ICE Steam Hybrid
becuase... running a sirling off the heat from the engine coolant and block is innefficient? On 12/20/05, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: Finally, someone finds a practical way to use the wasted ICE heat: http://www.gizmag.com/go/4936/The concept uses energy from the exhaust gasses of the traditionalInternal Combustion Engine (ICE) to power a steam engine which alsocontributes power to the automobile ? an overall 15 per cent improvement for the combined drive system.___Try the New Netscape Mail Today!Virtually Spam-Free | More Storage | Import Your Contact List http://mail.netscape.com-- Monsieur l'abbé, I detest what you write, but I would give my life to make it possible for you to continue to writeVoltaire
Re: BMW ICE Steam Hybrid
If so, all ya gotta do is make the post heat-exchange exhaust pipe bigger. -Original Message- From: Merlyn Yup, but do they run into problems with backpressure? ___ Try the New Netscape Mail Today! Virtually Spam-Free | More Storage | Import Your Contact List http://mail.netscape.com
Re: BMW ICE Steam Hybrid
leaking pen wrote: becuase... running a sirling off the heat from the engine coolant and block is innefficient? Who says the actual engines they're using aren't similar to Stirling engines? They pipe the hot fluids to a pair of expansion units but the article doesn't say what's inside those units. In any case recapturing 80% of the exhaust heat sounds pretty impressive to me. Looks like they had a glance at steam locomotives before they designed it :-) ... notice that both circuits, low and hi temp, first make steam (or should we say steam -- not sure it's actually water they're boiling!) and then superheat it at the back of the exhaust pipe? The old steam locomotives used a very similar trick, boiling the water and then running the steam through the boiler again before using it. Of course the second pass is upstream of the first pass in the exhaust circuit. Did you notice the photo of a man holding his hand on the exhaust pipe with the engine operating? Pretty cool... Notice also that both system, low and high temp, use the radiator of the car for the cold reservoir. The first stage of the low-temp circuit appears to suck hot water directly from the engine and dump the heat from it into the radiator. In fact, the diagrams make it appear as though there is no longer any direct connection from the engine to the radiator. And elsewhere, Merlyn said: Yup, but do they run into problems with backpressure? Cooling the exhaust necessitates that it becomes denser. I have heard that backpressure can be a problem with exhaust cooling, but do not have the references handy. [Again, that's Merlyn, not LP!] I would suspect not, for a couple reasons. First, muffling an engine puts a _lot_ of backpressure on it, and takes away about 10% of its power IIRC. (This is one reason small airplanes are often so noisy -- a muffler would be too big a power drain.) But note that they can probably ditch at least one muffler when they put this in the exhaust system: going through a heat exchanger very probably has about the same effect on the noise as going over the baffles of a conventional muffler. So, they're most likely trading one source of backpressure for another, rather than just adding one. (I assume BMW's normally have more than one muffler, of course!) Second, boat engines have used water-cooled manifolds for just about ever and they apparently work just fine. No doubt a little power is stolen, but that's the only bad consequence AFAIK. And according to the numbers, BMW's seeing a significant increase in power from this, so they're clearly reclaiming more energy than they're losing through the backpressure increase. Keep in mind that the cost of the backpressure is really just the cost of pumping the exhaust through the heat-exchanger. Surely, one can arrange a heat-exchanger to extract more heat from hot gasses than the pump that operates it consumes; otherwise steam engines couldn't work! On 12/20/05, [EMAIL PROTECTED] mailto:[EMAIL PROTECTED]* [EMAIL PROTECTED] mailto:[EMAIL PROTECTED] wrote: Finally, someone finds a practical way to use the wasted ICE heat: http://www.gizmag.com/go/4936/ The concept uses energy from the exhaust gasses of the traditional Internal Combustion Engine (ICE) to power a steam engine which also contributes power to the automobile ? an overall 15 per cent improvement for the combined drive system. ___ Try the New Netscape Mail Today! Virtually Spam-Free | More Storage | Import Your Contact List http://mail.netscape.com -- Monsieur l'abbé, I detest what you write, but I would give my life to make it possible for you to continue to write Voltaire
Re: BMW ICE Steam Hybrid
okay, i hadnt looked that close at the schematics. you're right, they ARE using the other waste heat as well. On 12/20/05, Stephen A. Lawrence [EMAIL PROTECTED] wrote: leaking pen wrote: becuase...running a sirling off the heat from the engine coolant and block is innefficient?Who says the actual engines they're using aren't similar to Stirlingengines?They pipe the hot fluids to a pair of expansion units butthe article doesn't say what's inside those units. In any case recapturing 80% of the exhaust heat sounds pretty impressiveto me.Looks like they had a glance at steam locomotives before they designedit :-) ... notice that both circuits, low and hi temp, first make steam (or should we say steam -- not sure it's actually water they'reboiling!) and then superheat it at the back of the exhaust pipe?Theold steam locomotives used a very similar trick, boiling the water and then running the steam through the boiler again before using it.Ofcourse the second pass is upstream of the first pass in the exhaustcircuit.Did you notice the photo of a man holding his hand on the exhaust pipe with the engine operating?Pretty cool...Notice also that both system, low and high temp, use the radiator of thecar for the cold reservoir.The first stage of the low-temp circuit appears to suck hot water directly from the engine and dump the heatfrom it into the radiator.In fact, the diagrams make it appear asthough there is no longer any direct connection from the engine to the radiator.And elsewhere, Merlyn said: Yup, but do they run into problems with backpressure? Cooling the exhaust necessitates that it becomes denser.I have heard that backpressure can be a problem with exhaust cooling, but do not have the references handy.[Again, that's Merlyn, not LP!]I would suspect not, for a couple reasons.First, muffling an engine puts a _lot_ of backpressure on it, and takes away about 10% of its power IIRC.(This is one reason small airplanesare often so noisy -- a muffler would be too big a power drain.)Butnote that they can probably ditch at least one muffler when they put this in the exhaust system:going through a heat exchanger veryprobably has about the same effect on the noise as going over thebaffles of a conventional muffler.So, they're most likely trading onesource of backpressure for another, rather than just adding one.(I assume BMW's normally have more than one muffler, of course!)Second, boat engines have used water-cooled manifolds for just aboutever and they apparently work just fine.No doubt a little power isstolen, but that's the only bad consequence AFAIK.And according to the numbers, BMW's seeing a significant increase in power from this, sothey're clearly reclaiming more energy than they're losing through thebackpressure increase.Keep in mind that the cost of the backpressure is really just the cost of pumping the exhaust through the heat-exchanger.Surely, onecan arrange a heat-exchanger to extract more heat from hot gasses thanthe pump that operates it consumes; otherwise steam engines couldn't work! On 12/20/05, *[EMAIL PROTECTED] mailto:[EMAIL PROTECTED]* [EMAIL PROTECTED] mailto:[EMAIL PROTECTED] wrote: Finally, someone finds a practical way to use the wasted ICE heat: http://www.gizmag.com/go/4936/ The concept uses energy from the exhaust gasses of the traditional Internal Combustion Engine (ICE) to power a steam engine which also contributes power to the automobile ? an overall 15 per cent improvement for the combined drive system. ___ Try the New Netscape Mail Today! Virtually Spam-Free | More Storage | Import Your Contact List http://mail.netscape.com -- Monsieur l'abbé, I detest what you write, but I would give my life to make it possible for you to continue to writeVoltaire-- Monsieur l'abbé, I detest what you write, but I would give my life to make it possible for you to continue to writeVoltaire
