I have been given this task to find out the Research Octane Number (RON) and the Motor Octane Number (MON) of TX stream and I'm not aware as to how this can be done? Can anyone guide me to the instrumentation technique required and the experimental procedure employed.
Research octane number is determined through several titrations, which basically yield the average carbon chain length and fraction of double bonds. Motor octane rating is determined by running the fuel in a small engine with adjustable compression ratio, usually accomplished with eccentric crankshaft bearings. Gas pumps in the US have a sticker on them that says, "minimum octane rating (R+M)/2" which means that the average of research and motor octane ratings for this fuel is at least 89, 91, 93, or whatever. There is some interesting history behind having both ratings, as the unleaded suppliers thought they were not being credited as well as the leaded suppliers. Even though lead was removed long ago, the two ratings have persisted. Also, you should know that normal (straight chain) octane has a rating of 0 and iso-octane has a rating of 100. There is very little (if any) iso-octane in gasoline, even in the 1970s at the height of the motor car industry. You pay a premium for high octane fuel, not because it has more energy, but it's harder to ignite, avoiding detonation and knock. Diesel fuel when compressed and atomized explodes even without a spark plug plus diesel has more energy per unit mass than gasoline. Most consumers and even many engineers are ignorant of these important details.
RON describes the performance of an engine fuel at low temperatures and low speeds. We can obtain a value for RON by determining the performance of the fuel in a test engine and comparing the results with different mixtures of isooctane and heptane in the same engine.
MON describes the performance of an engine furl at high temperatures and high speeds. Unlike in the determination of RON, the speed we should consider in determining the MON is 900 rpm.
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