Test your vocabulary with our 10-question quiz! Octane number is also known as octane rating. HCCI: Homogeneous Charge Compression Ignition, The Difference Between Deflagration and Detonation, What Is a Molotov Cocktail? The cetane number refers to the eace with which desel fuel ignites easily at a relatively low temperature. Updated with more commonly confused words! Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free! The octane number of a fuel, especially gasoline, is a measure of its anti-knock properties. Octane Level, also known as octane rating or octane number is the standard measure of the performance fuel for an internal combustion engine. In United States, I have understood that octane numbers are generally lower than in Europe for two reasons. n. A numerical representation of the antiknock properties of motor fuel, compared with a standard reference fuel, such as isooctane, which has an octane number of 100. Delivered to your inbox! Motor octane number synonyms, Motor octane number pronunciation, Motor octane number translation, English dictionary definition of Motor octane number. octane number , rating n a measure of the quality of a petrol expressed as the percentage of isooctane in a mixture of isooctane and n-heptane that gives a fuel … Octane number definition differences in different countries. 2021. Fuel having high Octane number is considered as Ideal fuel for the Gasoline engine. In contrast, fuels with lower octane numbers (but higher cetane numbers) are ideal for diesel engines, because diesel engines (also referred to as compression-ignition … Octane Number (RON, MON) & Knock Resistance The octane number (ON) is a measure of the knock resistance of gasoline. The detonation produces higher pressure than the engine may be able to withstand. Most fuels have an octane rating in the range of 100 to 0. Please tell us where you read or heard it (including the quote, if possible). Cetane Number measures the ignition delay of the fuel in the diesel engine. octane number meaning: 1. a number showing the quality of petrol by representing how well and with how much power it can…. Post the Definition of octane number to Facebook, Share the Definition of octane number on Twitter. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Octane number definition, (of gasoline) a designation of antiknock quality, numerically equal to the percentage of isooctane by volume in a mixture of isooctane and normal heptane that matches the given gasoline in antiknock characteristics. Dictionary entry overview: What does octane number mean? Viewed 2k times 3. Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. More from Merriam-Webster on octane number, Britannica.com: Encyclopedia article about octane number. Using Ethanol's Double Octane Boosting Effect with Low RON Naphtha-Based Fuel for an Octane … Rankovic N, Bourhis G., Loos M., and Dauphin R., "Understanding octane number evolution for enabling alternative low RON refinery streams and octane boosters as transportation fuels", Fuel, vol. Octane number, also called Antiknock Rating, measure of the ability of a fuel to resist knocking when ignited in a mixture with air in the cylinder of an internal-combustion engine.The octane number is determined by comparing, under standard conditions, the knock intensity of the fuel with that of blends of two reference fuels: iso-octane, which resists knocking, and heptane, which knocks readily. Comparative Study on Gasoline HCCI and DICI Combustion in High Load Range with High Compression Ratio for Passenger Cars Application Octane Number measures the ability of a fuel to resist pre-ignition of the fuel in the gasoline engine. Updated September 09, 2019. Reader Question: Should gasoline or kerosene be burned in a diesel engine? An octane rating, or octane number, is a standard measure of the performance of an engine or aviation gasoline. The higher the octane number, the more compression the fuel can withstand before detonating. The cetane number is similar to the octane rating in that it is a rating assigned to a fuel to rate the quality of its combustion. Octane number - definition A figure indicating the anti-knock properties of a fuel, based on a comparison with a mixture of iso octane and heptane. INTRODUCTION Octane Number o It’s a standard measure of the performance of an engine. Fuels with high octane numbers are used in high performance gasoline engines. Helmenstine, Anne Marie, Ph.D. (2020, August 25). Arbitrarily, pure iso-octane (2,2,4-trimethylpentane) is accorded a research octane number of 100, while the straight-chain paraffin n-heptane is given an octane number of zero. Send us feedback. The octane number of a fuel, especially gasoline, is a measure of its anti-knock properties. Fuels with low octane number (or high cetane numbers) are used in diesel engines, where fuel is not compressed. In a spark-ignition engine, using a fuel with too low an octane rating can lead to pre-ignition and engine knock, which can cause engine damage. Gasoline characteristics that have an important effect on engines and emissions include its octane number and chemical composition. Ask Question Asked 4 years, 1 month ago. She has taught science courses at the high school, college, and graduate levels. In other words, the fuel can cause the engine to undergo knocking when burnt. These example sentences are selected automatically from various online news sources to reflect current usage of the word 'octane number.' What You Should Know About the Diesel Fuel Cetane. 1. a measure of the antiknock properties of gasoline Familiarity information: OCTANE NUMBER used as a noun is very rare. American Heritage® Dictionary of the English Language, Fifth Edition. 'Nip it in the butt' or 'Nip it in the bud'. Also called octane rating. Octane number definition is - a number that is used to measure the antiknock properties of a liquid motor fuel (such as gasoline) with a higher number indicating a … Octane number is also known as octane rating. The higher the octane number, the more compression required for fuel ignition. Basically, compressing the air-fuel mixture may cause fuel to detonate before the flame front from the spark plug reaches it. In broad terms, fuels with a higher octane rating are used in high-performance gasoline engines that achieve higher compression ratios. OCTANE NUMBER AND CETANE NUMBER Cetane number (diesel fuel) and octane number (gasoline) both measure the tendency of the fuel to ignite spontaneously. Definition - What does Octane Level mean? Helmenstine, Anne Marie, Ph.D. "Octane Number Definition and Example." Definition Of Octane Number : Thus, the octane number of any fuel is defined ‘as the percentage of iso-octane in a mixture of iso-octane and n-heptane that has the same knocking as … ThoughtCo. “Octane number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/octane%20number. A mixture of compounds with an identical tendency to auto-ignite, under the same conditions of compression, would thus also be given an octane rating of 95. So fuels with a higher octane rating are useful in high-performance gasoline engines that require higher compression ratios. The octane rating of a fuel is also sometimes referred to as the octane number of the fuel. Octane Number Definition and Example. Firstly, the gasoline is often genuinely lower-octane. It is also called the antiknock rate of fuel. Accessed 12 Mar. https://www.thoughtco.com/definition-of-octane-number-604586 (accessed March 12, 2021). 'All Intensive Purposes' or 'All Intents and Purposes'? An octane rating, or octane number, is a standard measure of the performance of an engine or aviation fuel. Hence, octane number definition is extended to allow octane numbers higher than 100. Gasoline characteristics that have an important effect on engines and emissions include its octane number and chemical composition. An octane rating of 100 indicates minimal to no knocking (iso-octane), whereas an octane rating of 0 implies that the fuel has a very high knocking tendency (heptane). ‘The higher the octane number you see on a gas pump, the more the fuel can be compressed before it explodes.’ ‘However, ethanol has a good octane rating of around 112 and a high heat-off evaporation so it cools down the intake charge.’ ‘Pyrolysis oil can also be added to gasoline to increase its octane rating.’ A compound What Is Common Rail Direct Injection (CRD)? Definition and Explanation, The Properties and Applications of Platinum, Ph.D., Biomedical Sciences, University of Tennessee at Knoxville, B.A., Physics and Mathematics, Hastings College. 4. octane number. When fuel is used in an engine, the engine will generate a knocking effect. In Britain standard unleaded gasoline is 95RON. octane number (Noun) a measure of the antiknock properties of an automobile fuel; isooctane having an octane number of 100, a fuel with the same antiknock properties as a mixture of 90% isooctane and 10% heptane having an octane number of 90 Helmenstine, Anne Marie, Ph.D. "Octane Number Definition and Example." The higher the number, the better the fuel burns within the engine of a vehicle. Active 4 years, 1 month ago. The higher an octane number, the more stable the fuel. Noun 1. octane rating - a measure of the antiknock properties of gasoline octane number quantity, measure, amount - how much there is … The octane number is actually the simple average of two different octane rating methods— motor octane rating (MOR) and research octane rating (RON)—that differ primarily in the specifics of the operating conditions.