ækvivalensforhold

ækvivalensforhold is a Danish term that translates to equivalence ratio in English. It is a fundamental concept used in chemistry and engineering, particularly in combustion processes and chemical reactions. The equivalence ratio quantifies the relative amounts of fuel and oxidant present in a system. It is defined as the ratio of the actual fuel-air ratio to the stoichiometric fuel-air ratio.

A stoichiometric mixture is one where the amounts of fuel and oxidant are precisely in the proportions required for complete combustion, with no excess of either reactant. An equivalence ratio of one (φ = 1) signifies a stoichiometric mixture. When the equivalence ratio is less than one (φ < 1), it indicates a fuel-lean mixture, meaning there is more oxidant than is needed for complete combustion. Conversely, an equivalence ratio greater than one (φ > 1) signifies a fuel-rich mixture, where there is insufficient oxidant for complete combustion of all the fuel.

Understanding the equivalence ratio is crucial for controlling and optimizing combustion efficiency, emissions, and performance in engines, furnaces, and other combustion devices. It influences factors such as flame temperature, pollutant formation (like NOx and carbon monoxide), and fuel consumption. In chemical synthesis, the equivalence ratio helps determine reaction completeness and product yield. The concept is widely applied in fields ranging from automotive engineering to industrial chemical processes.