Method for generating a shell mold for a casting

A method for generating a shell mold for a casting, the method comprising:

• recording a real surface geometry of the casting;
• generating a coherent base mesh based on the real surface geometry, the coherent base mesh composed of surface elements connected by base node points and defining an interior surface of the shell mold;
• generating a shell vector for each base node point, wherein the shell vector is oriented perpendicular to a pseudo-tangential plane at the respective base node point, the shell vector has a length generated as a function of curvature characteristics of the base mesh at the base node point and the shell vector ends at a shell node point, and wherein the length of the shell vector corresponds to a distance to a first surface element which is positioned above each base node point which, together with all other first surface elements, forms a first layer of the shell mold;
• correcting the first layer of the shell mold based on a local edge length of the adjacent surface elements and/or a surface internal angle of the adjacent surface elements;
• generating a shell mesh based on the shell node points of the corrected first layer;
• generating a subsequent shell vector for each shell node point, wherein the subsequent shell vector is oriented perpendicular to the respective shell node point, the subsequent shell vector has a length generated as a function of curvature characteristics of the shell mesh at the shell node point, and the subsequent shell vector ends at a subsequent shell node point, and wherein the length of the subsequent shell vector corresponds to a distance to a subsequent surface element which is positioned above each shell node point which, together with all other subsequent surface elements, forms a subsequent layer of the shell mold;
• and
• correcting the first layer of the shell mold based on a local edge length of the adjacent surface elements and/or a surface internal angle of the adjacent surface elements;
• repeating the generation of the shell mesh, the generation of the subsequent shell vector and the correction of the shell mesh to form a desired number of subsequent layers of the shell mold resulting in a predetermined final thickness of the shell mold,
• wherein the shell mold is described from a multiplicity of finite volume elements and/or surface elements which are connected to one another via base node points or shell node points and which together describe the surface of the shell mold,
• wherein curvature characteristics of the base mesh at the base node point are determined by summing an apex angle between a surface normal and adjoining edges and by applying a weighting factor based on an arc cos function of tangential vectors.