An Investigation on the Formation Mechanisms of Carbon Monoxide in Enclosure Fires Happening In Tall Timber Buildings: An Atomistic Approach

Description

Timber building has becomes an innovative and sustainable architectural solution in view of the research on wood mechanics and bio-spired materials in the past few decades. However, the safety issue related to the wood combustion is still a concern before wood can be applied to building construction extensive.? In fact, the question related to wood pyrolysis and decomposition remains unanswered.? In particular, little is known with regard to the formation mechanism of toxic carbon monoxide in timber building fire.? Prior research studies in this area mainly focus on the experimental approach. It is found that the carbon monoxide yields at least double in wood when there is a vitiation of oxygen supply, which can be easily in tall buildings suffered from fire attacks.? However, these findings cannot give any clues upon the formation mechanism of carbon monoxide, which is fundamental and crucial for a comprehensive understanding upon wood combustion. Such mechanism is indeed important for designing the fire safety aspect of the tall timber building, especially related to the evacuation route during fire. Through the recent development of material modeling technique, molecular dynamics simulation equipped with reactive force field is capable to reveal the decomposition of the wood constituents from an atomistic perspective, so that the formation mechanism of carbon monoxide under different oxygen content can be explored.The objective of this research is to investigate the formation mechanism of carbon monoxide fundamentally and comprehensively using reactive molecular dynamics simulation equipped with bench-scale fire tests. It is proposed to investigate by means of a synergistic effort that consists of atomistic modeling of cellulose, hemicellulose and lignin, reactive molecular dynamics simulations of carbon monoxide formation during wood combustion, fire tests from material level, modeling smoke and gas flow in tall timber building during fire using computational fluid mechanics. Synergizing the knowledge developed in these research tasks, this study will form the basis for augmenting existing design specifications for tall timber building by including the quantitative fire safety design related to the carbon monoxide formation during wood combustion, leading to a much more reliable and sustainable design.? It is envisioned that this proposed research is crucial for understanding the complete and incomplete combustion processes, which leads to an advancement of thermal and combustion science of timber-based materials, and for understanding the relative rating of their flammability and fire safety, which is crucial when wood is used in tall building design.