1. A method for creating a curved surface model, comprising: acquiring an already input section line of a target object; dividing three-dimensional space into zones using a plane on which the already input section line of the target object is located; generating, according to a shape of each zone and a section line comprised in each zone, a geometry located within each zone, wherein the section line comprised in each zone is interpolated into the surface of the geometry; extracting the surface of the geometry located within each zone to generate a sub-curved surface located within each zone, wherein a section line comprised in a zone where the sub-curved surface is located is interpolated into the sub-curved surface; and splicing the sub-curved surfaces to obtain a curved surface model of the target object, wherein after dividing the three-dimensional space into zones using the plane on which the already input section line of the target object is located, the method further comprises determining a type of each zone to process zones of a same type using a same processing method, and wherein determining the type of each zone comprises: determining that the zone is a body zone when section lines are comprised on two or more planes in all planes constituting a zone; determining that the zone is an end zone when a section line is comprised on only one plane in all planes constituting a zone; and determining that the zone is an empty zone when a section line is not comprised on any plane in all planes constituting a zone.