Post by: Winston Smith on June 05, 2005, 10:58:28 AM
How do internal combustion engines work? What, exactly is knock. How is it eliminatd?
Thanks for your help
Post by: Iain on June 05, 2005, 11:03:44 AM
http://www.schoolscience.co.uk/content/4/chemistry/petroleum/knowl/4/2index.htm?knock.html
World at your fingertips, cool stuff.
Post by: Sindawe on June 05, 2005, 11:20:21 AM
http://en.wikipedia.org/wiki/Internal_combustion_engine
Engine knock
http://en.wikipedia.org/wiki/Engine_knock
Post by: K Frame on June 05, 2005, 05:59:01 PM
Engine knock was a HUGE problem in the old days until a chemist by the name of Thomas Midgely finally discovered the cause, and the first effective anti-knock compound, tetra-ethyl lead.
Invention and Technology had a big article on the guy a couple of years ago. A real renaissance man who ended up accidentally hanging himself with a device he designed to enhance his mobility after he contracted, I believe, polio.
Post by: Preacherman on June 06, 2005, 05:37:55 AM
Post by: Fly320s on June 06, 2005, 08:41:30 AM
Answer: Suck, squeeze, bang, and blow.
Post by: cfabe on June 06, 2005, 11:25:49 AM
Quote from: Fly320s
Answer: Suck, squeeze, bang, and blow.
Or on a 2-stroke, "finish exhaust, intake, and squeeze", "bang, blow, pressurize intake charge in crankcase, and begin intake"
Post by: Antibubba on June 07, 2005, 01:16:11 AM
Post by: cfabe on June 07, 2005, 03:56:30 AM
Atkinson was another engine inventor who developed a slightly different engine, to get around Otto's patents. Main differences are that his piston-crankshaft linkage was more complex, using a pivot and a second link, and that he controlled the engine's power output by adjusting the intake valve timing rather than using a throttle valve to restrict the intake charge. This different method of power control ended up being more efficient because it reduced pumping losses (sucking through a closed throttle valve) at low rpms and loads, where most driving is done. The prius uses this intake valve timing method, and has a slightly offset crankshaft to reduce piston-cylinder frictional losses, but just uses one con rod, not the multi-link setup that Atkinson originally used. It's still a 4-stroke suck-squeeze-bang-blow engine, just the suck happens a little differently, and the geometry is changed a little bit. Overall result is that it's more efficent in the power areas where a car engine is typically operated.
Post by: mfree on June 07, 2005, 05:12:32 AM
Diesel is ICE too, except the fuel is injected near top compression and the heat of the compressed charge lights the fuel. All else is relatively the same, except for Detroit's two strokes.
Two stroke engines are another ball of wax for ICE altogether. LOTS of variants there, reed valve, piston shroud valve, orbital DI engines, forced induction/evacuation methods, etc.
Post by: atek3 on June 07, 2005, 10:47:14 AM
Oh the crankshaft's connected to the timing bone, the timing bone's connected to the camshaft bone, the camshaft bone's connected to the cam lobe bone, the cam lobe bone's connected to the lifter bone, the lifter bone's connected to the pushrod bone, the pushrod bone's connected to the rocker arm bone, The rocker arm bone's connected to the valve bone.
atek3
Post by: cfabe on June 07, 2005, 10:57:45 AM
Post by: atek3 on June 07, 2005, 11:12:59 AM
atek3
Post by: Stickjockey on June 07, 2005, 03:39:47 PM
Yet another very informative site. May I also reccommend finding a copy of Department of the Army TM9-8, "Principles of Automotive Vehicles." A bit outdated, but still more information about almost anything with an engine than you would ever want to know.