One-dimensional plant model unsteady flow evaluation method, evaluation system, and storage medium

摘要

PROBLEM TO BE SOLVED: To enable flexibly coping with partial change of boundary conditions such as erroneous closing of a valve and breakdown of a channel, by not using a coefficient matrix integrating the relation of each portion of a channel network, and cooperating softwares developed every constituent as it is. SOLUTION: In an estimating method of a one-dimensional plant model, branch points or confluent points of fluid in a channel network constituted of a plurality of constituting apparatuses and piping connecting the apparatuses are made junctions (11, 13, 16), and the constituting apparatuses (a pump 10, an intermediate heat exchanger 12, an air cooler 14, a vapor generator 15) are made nodes. A process wherein mass conserving error is distributed in inverse proportion to the fluid inertial value of each node connected with each junction, and the rate of change of flow rate of each node is calculated from an equation of motion is repeated. The flow rate of each node is obtained by adding the change of flow rate calculated from the rate of change of flow rate and time notching interval at the time when the mass conserving error becomes at most a specified value.