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Hot Blast Stove offering hot blast to blast furnace is a necessary equipment for combustion and heat transfer ,with complicated pipe system ,the stability of the pipe system in Hot Blast Stove is one of the most important factors that affecting longevity and high temperature. Finding the important reason of integrate combined numerical, spot-test and experiment also, general analysis all the factors.Study the gas dynamic characteristic based on non-steady flow theory of gas. First, calculating the pressure pulsation in the condition of different velocity and pulsant frequency through using CFD software, then calculate the ahead natural frequency and length of resonance, which offer a reference to the select of pipe length in Hot Blast Stove. At the same time, study the influence of temperature further more, through changing the preheating temperature of the gas, make the nature frequency of gas away from the nature frequency of pipe structure and excitation frequency to avoid resonance. Using ANSYS finite element software to calculate ahead nature frequency and match models of it, and discuss the influence of structure nature frequency in different preheating temperature, pressure and velocity according to the characteristic of pipe system. After knowing the structure nature frequency, optimize the structure, such as disposal the point of support, reduce the number of elbow, change the thickness of pipe, setting the dilatant and so on, which offer a basic to avoid resonance.Then the flow in the curved pipe and reducing pipe was simulated through using CFD software, know that fluid passing curved pipe, reducing pipe can form secondary flow, vortex shedding, circumfluence, occur separation of boundary layer and periodic circulation flow, make the fluid pulsant, then cause the pipe vibrancy. It is one of the efficient method that reducing the number of elbow and reducing pipe when the pipe system vibrante.At last, the pipe system was researched through water model experiment, using CCD Optional Imagin system, at the same time, analysis the signal from spot-test ,and compared with numerical and experiment, the results indicate: when the range of gas pulsation frequency approach the gas nature frequency and structure nature frequency , the pipe will vibrant, which offer a basis to reduce vibrancy of the pipe system.
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