Questions tagged [combustion]

70 questions
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Why afterburners are needed instead of burning more fuel inside the turbine?

I'm reading this article on afterburners: https://www.airspacemag.com/flight-today/how-things-work-afterburners-18481403/ It says in the article: A typical jet engine uses only about half the oxygen it ingests, leaving a large amount of potential…
S. Rotos
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Derivation for the Formulas of the Approximate Ultimate Analysis of Coal

I've been given the following to memorize; But my head is so crammed with many others that I need to find another way; Are these formulas Empirical? I was hoping that if I derive it from a much more primitive form; I maybe able to remember it. $${…
james
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3
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Advice on simple spark ignition system

I'm looking for any tips on a simple and cheap means of generating a regular spark for ignition of propane in air, could be electrical or other but needs to be simple and fairly reliable. Criteria are : needs to remotely ignite/re-ignite a…
Chris Johns
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Trouble with Valveless PulseJet

My friend and I are working on building a valveless pulsejet out of sheet metal. We initially built a small one (a few feet in length) using the below dimensions: The issue was that we were unable to get it running without compressed air. When we…
andycate
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Calculating Mass Fractions of a Hydrogen and Oxygen Gas Mixture Pre Ignition

I am trying to calculate mass fractions of a Hydrogen Oxygen gas mixture as a function of equivalence ratio before ignition. My work is the following: Equivalence Ratio:…
Unique Worldline
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