1. A computerized analysis method for estimating a kneaded state of a fluid, comprising the steps of: defining a kneading space model which is a three-dimensional finite element model of a kneading space within which the fluid is kneaded; defining a fluid model of the fluid; defining the fluid model in the kneading space model so as to fill less than 100% of the kneading space and defining necessary kneading conditions; tracking a particle tracking, comprising the steps of: arranging a plurality of first virtual particles in the kneading space model; making a flow calculation of the fluid model based on the kneading conditions; tracking the first virtual particles disposed in the fluid model; and obtaining positions of the first virtual particles, wherein each first virtual particle is treated as having no dimension and no mass and exerting no influence on the flow calculation of the fluid model and further being movable according to the flow of the fluid model; and performing an estimation, comprising the steps of: uniformly and fixedly arranging a plurality of second virtual particles in the kneading space model, wherein each second virtual particle is treated as having no dimension and no mass and exerting no influence on the flow calculation; calculating fluid positions at which the current fluid model resides from the positions of the first virtual particles in the particle tracking step; obtaining positions of the second virtual particles which are uniformly and fixedly arranged and which reside at said fluid positions; defining the obtained positions of the second virtual particles as an ideal kneaded state; obtaining a degree of coincidence between the obtained positions of the second virtual particles and the positions of the first virtual particles obtained in the particle tracking step; defining the obtained degree of coincidence as degree of kneading of the fluid model; and developing a kneading machine according to the degree of kneading of the fluid model to perform an actual kneading process.