压差是建筑火灾中烟气流动的主要驱动力之一,建筑的防排烟系统必须考虑如何增加或减小这种驱动力,以控制烟气的流动与蔓延。本文在双区模型基础上,对火灾条件下室内外压差分布特点进行了分析,给出了自然充填、自然排烟和机械排烟过程中内外压差的计算方法。 Pressure drop is one of the main driving forces for smoke flow in building fire. Building smoke control system must consider how to increase or decrease this driving force to control the flow and spread of flue gas. Based on the two-zone model, this paper analyzes the distribution of indoor and outdoor pressure in fire conditions, and gives the calculation method of internal and external pressure difference during natural filling, natural exhaust and mechanical exhaust.