Hi, Just for the record, some may be wondering just exactly what a Turbine is. (I studied Aeronautical Engineering, but it has been a few years.) ;-) I'll try to put it in non-aeronautic speak, to the best of my memory. A turbine is a set of "propellers", all one after the other, on the same shaft. If functions exactly opposite to a propeller. A propeller takes rotational energy from the motor and pushes the air back, providing thrust. A turbine sits in a speeding stream of air, slowing down the air, and producing rotational energy (typically for driving a generator of some type). An aircraft jet engine has a turbine in it, although not all turbines are in jet engines. Some turbines are in power stations, where steam is turned into rotational energy, which drives a generator, which produces electric power. A jet engine relies on burning fuel to thrust air out the back of the engine for its thrust. It does not act at all like a propeller. A jet engine is made up of several stages: the fan, the compressor, the combustion chamber, the turbine, and the nozzle. The fan, compressor, and turbine all have "blades" that look sort of like propeller blades, but none of them has the function of a propeller. All of these are connected to the same shaft, but at their respective stages. * Fan - looks like a big propeller, but its purpose is not to produce thrust. It rotates within a large housing called a "cowling". It's purpose is to "pre-compress" the air flowing into the compressor. * Compressor - Precompressed air from the fan flows into the compressor. The compressor has many rows of blades to compress the air to a higher and higher pressure as it approaches the combustion chamber. The purpose of this is that combustion produces a lot more energy when it occurs at high pressure. So the compressor's job is to get the air to a high pressure so that you get the most bang per gallon of fuel in combustion. * Combustion chamber - Fuel is mixed with the high pressure air and ignited. The explosion (burn process) and the shape of the chamber cause the air to rush out the back of the engine at high speed. * Turbine - On its way out of the engine, the air flows over the turbine, which looks exactly like the compressor but in reverse. Its job is to steal some of the energy back from the exiting gases in order to keep driving the compressor and fan and thus keep the engine running. * Nozzle - The chamber where the gases (air and burned fuel) escape from the jet engine is shaped in a special way to facilitate maximum speedup of the air and hence maximum thrust. There! That's your annual dose of thermodynamics and aerodynamics. ;-) So... how is this relevant to the logo hunt? If you do a side view, you probably ought to stack up a set of "propellers", one in front of the other to be more like a turbine. It appears the logo hunt is going more in the direction of the simple "saw blade" over "turbine". That looks pretty nice. Real turbines have straight blades and always operate within a housing. (add an outer circle perhaps? maybe I will try this.) Nonetheless, the "saw blade's" swept blades (not straight) do give the impression of rotation. Anyway, I hope this background was mildly interesting, though not completely relevant. Stephen At 11:59 PM 7/20/00 -0700, you wrote: >on 7/20/2000 11:26 PM, "Leon Messerschmidt" <[EMAIL PROTECTED]> wrote: > >> Haven't seen Rafal's logo yet, but these would my be first choice at the >> moment - maybe >> add a dash of color? :-) >> >> ~ Leon > >nice, but propellers aren't turbines. > >-jon > ------------------------------------------------------------ To subscribe: [EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Search: <http://www.mail-archive.com/turbine%40list.working-dogs.com/> Problems?: [EMAIL PROTECTED]
