As an application of large scale distributed network computing system, RAM Grid tries to solve the problem of memory resource sharing and utilization. Due to the special properties of memory, traditional resource information management approaches cannot be adapted easily. This paper proposes a clustering based resource aggregating scheme under the background of RAM Grid, which can reduce the scale of resource information management efficiently. With analogy to the force field and potential energy theory in physics, the basic model, the force field-potential energy model, and the corresponding distributed algorithms are proposed, respectively. The model and algorithms are also evaluated by real network topologies based simulation.