By building fitting curve,we explore the characteristics of bed resistance and identify the critical fluidizing air blast;By conbining the fitting data,we build relations between bed air pressure,air chamber pressure and bed thickness,and forcast the bed thickness of running boiler.

Numerical simulation and analysis of smoke characteristics and critical velocity in underground railway tunnel while fire;

Furthermore, a critical velocity of air flow expression for transition from upward smoldering to flaming combustion is constructed.

The model for calculating the critical velocity in a tunnel cross-passage is established on the basis of the critical Froude theory.

Based on vibration theory,this paper presents concise methods for critical wind speed,Vcr,at which tube members start the aeolian vibration,and resonance force calculations,and analyzes the influences of resonant bending and fatigue stress on safety of web and auxiliary members that are subject to the aeolian vibration.

The three-series solution is taken up to the nonlinear differential equation of the galloping movement caused by the cross wind force acting on a high-rise structure, thus giving a reduced 3D expression in terms of steady-state response and critical wind speed.

At the same time,it analysis relative factors of smoke control in the tunnal, and gives the critical wind speed of smoke control in the typical tunnel.

We study the properties of doubling rate-risk function and critical risk and estimate the the maximal and minimal risks.