Preface: Special Issue on Fire-Induced Smoke Movement and Control

1. Introduction

Generally, fires in confined spaces have more intense burning behaviors than open-space fires due to the accumulation of heat and smoke released by fires. Driven by increasingly rapid globalization and urbanization, the immense growth of building density and complexity has led to larger fire frequency and consequences [1]. This significant increase in building fire risks have raised extensive concerns about smoke transportation and control on confined-space fires through full-scale experiments [2,3], reduced-scale experiments [4,5], numerical simulations [6,7], and statistical analysis [8]. Today, a vast number of studies on fire-induced smoke movement and control are being continuously reported. It is important to provide state-of-the-art insight and strengthen the field knowledge. This Special Issue presents a collection of 12 papers that address the fundamental and practical problems of smoke movement and control in various buildings.

2. Descriptions

This Special Issue consists of research in two directions, including smoke movement under natural ventilation and smoke control, and establishes a firm foundation for future research in the field of fire-induced smoke movement and control. Efforts regarding smoke transportation law under natural ventilation have been emphasized due to the importance of determining fire hazards. The dimension effect (curvature [5] and tunnel width [9] of underground space; deck spacing of the double-deck bridge [10]) and fire source effect (heat release [5,11] and fire source location [9]) on two-dimensional temperature distribution and smoke layer entrainment have been quantified. These scientific articles contribute fire hazard assessment methods to various building fires.

Recently, the contribution to smoke control is increasing continuously. Smoke control can be divided into passive and active control technologies. In terms of passive smoke control, a methodology for field testing of smoke control properties of fire facilities [12] and an optimized natural ventilator [13] have been provided. Compared to the passive method, active control receives more attention. Aiming at the underground space, ship engine room, and large atrium, the important design parameters of smoke control system, such as smoke vent layout [4], smoke exhaust rate [4,9,13], air supply volume [14], and longitudinal ventilation velocity [15,16,17], have been well-addressed. Advances in smoke exhaust strategies have the potential to guide engineering practice.

3. Future Research Direction

Although considerable progress has been made on fire-induced smoke movement and control, much work remains to be conducted. Firstly, the limitations of CFD fire modelling as the widely used method, i.e., long-lasting and costly computation, are still significant [1,18], and AI (artificial intelligence) with high-performance computing will have wider applications. Secondly, in recent years, extreme weather (e.g., heavy rainfall [19,20]) is becoming increasingly prevalent with global warming. The boundary condition describing the extreme environment will not be disregarded when studying confined space fires. Last but not least, with the complex interconnected infrastructures (e.g., underground interconnected tunnel [5,9]) and green buildings [21] rapidly emerging, the characteristics of smoke transportation in these new buildings will need to be concerned in the future.