Patent ID: 8682601

Claim:
A safety valve vibration analyzer that analyzes vibration of a valve disc in a safety valve, the safety valve analyzer comprising: an input unit in which set conditions of a physical model including the safety valve and an upstream pipe connected to the safety valve is inputted; a first holder that holds a safety valve governing equations including an equation of motion of the valve disc, a flow equation at the safety valve inlet, a flow equation at the safety valve outlet, and a mass conservation equation in a valve box; a second holder that holds a pipe governing equations including a mass conservation equation, an energy equation, and an equation of motion of a fluid flowing the upstream pipe; a third holder that holds a valve lifting force function representing the relation between the valve lift and a valve lifting force exerting on the valve disc; and a computer processing unit coupled to said input unit and said holders wherein said computer processing unit derives a time variation of a valve lift by using the set conditions inputted in the input unit, using the safety valve governing equations, including the equation of motion of the valve disc to which the valve lifting force function read from the third holder is applied, the flow equation at the safety valve inlet, the flow equation at the safety valve outlet and the mass conservation equation in a valve box, and using the pipe governing equations held in the second holder.