Abstract Air curtains (ACs) are plane turbulent impinging jets that are used to separate two environments in terms of heat and mass transfer while still allowing traffic between these environments. The many applications of ACs across a wide variety of industries makes the evaluation of their performance an important but difficult task. The aim of this paper is to introduce a performance indicator, called the adapted separation efficiency, that is suitable for different types of systems that may involve different AC configurations (downward blowing, upward blowing, lateral blowing, multiple jets, etc.) at multiple scales, different transported quantities (heat, water vapor, particles, gases, etc.) subjected to various transport mechanisms (advection, molecular and turbulent diffusion) and varying environmental conditions (gradients in environmental pressure and/or density). It is defined using a conventional efficiency formula. The principle of this performance indicator is illustrated with a generic case study where the performance is evaluated for two basic AC configurations involving cross-jet pressure and density gradients, as well as different jet momentum fluxes. The case study is conducted based on computational fluid dynamics employing validated large eddy simulations.

中文翻译：

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气幕性能：引入适应的分离效率

摘要 空气幕 (AC) 是平面湍流撞击射流，用于在传热和传质方面将两个环境分开，同时仍允许这些环境之间的交通。空调在各行各业的许多应用使得对其性能的评估成为一项重要但困难的任务。本文的目的是介绍一个性能指标，称为自适应分离效率，适用于可能涉及不同 AC 配置（下吹、上吹、侧吹、多射流等）的不同类型系统在多个尺度、不同的传输量（热量、水蒸气、颗粒、气体等）受到各种传输机制（平流、分子和湍流扩散）和不同的环境条件（环境压力和/或密度的梯度）。它是使用传统的效率公式定义的。该性能指标的原理通过一个通用案例研究来说明，其中评估两个基本 AC 配置的性能，涉及交叉射流压力和密度梯度，以及不同的射流动量通量。案例研究是基于计算流体动力学进行的，采用经过验证的大涡模拟。以及不同的射流动量通量。案例研究是基于计算流体动力学进行的，采用经过验证的大涡模拟。以及不同的射流动量通量。案例研究是基于计算流体动力学进行的，采用经过验证的大涡模拟。