Direct Numerical Simulations of Turbulent Spray Combustion: Behavior of Scalar Dissipation Rate By Abouelmagd Abdelsamie
نویسنده
چکیده
Scalar dissipation rate is an essential parameter in combustion theory; understanding its behavior is necessary for developing and improving combustion models. In most cases, the scalar dissipation rate shows different trends under different combustion conditions, and it is thus case-dependent. Spray combustion is categorized as a partially-premixed combustion system, leading to very complex processes. The objective of this work is to investigate the behavior of scalar dissipation rate in turbulent spray combustion using Direct Numerical Simulations (DNS). For this purpose, a temporally-evolving jet (TEJ) configuration has been examined. 3D simulations have been conducted using the in-house code DINO. This configuration constitutes a perfect numerical setting to investigate scalar dissipation rate, mixing, and shear in spray combustion. The conditional mean of scalar dissipation rate shows a non-monotonic behavior in mixture fraction space, highlighting the complexity of the interaction between spray, flame, and turbulence.
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