Parts and structures for aircraft and spacecraft are of increasingly large size, and in certain instances, parts and structures of this type are being produced monolithically out of carbon fibre reinforced plastics material (CFRP). Current commercial aircraft comprising wings having a wingspan much greater than 30 meters serve as an example. The wings comprise wing shells which are of a correspondingly large size. The shells are reinforced in a known manner using reinforcing elements, so-called stringers, the above-mentioned CFRP material generally serving as a material for the shells and the reinforcing elements. The shell and reinforcing elements will be referred to in the following in short as components and the assembly itself as a part.
The assembly of the shell and reinforcing elements is often produced in a monolithic manner, either the complete part, that is to say the shell having reinforcing elements arranged thereon, being cured in a curing process in an autoclave, or the shell being initially cured in an autoclave, then the reinforcing elements being fixed to the shell, and then this assembly of cured shell and uncured reinforcing elements being cured in an autoclave in a further curing process. It is however also conceivable that the reinforcing elements are initially cured, then the reinforcing elements are fixed to the uncured shell, and then this assembly is cured together in a curing process.
In any case, the part and components are subjected to a change in their physical properties by the curing, during which heat is released due to a chemical reaction, that is to say that the part and components change, for example in length and orientation, and as a result undesirable warpings, or component distortion, may occur in the end product, that is to say the part, which warpings are for example physically described as moments and distortion angles. A major reason for the occurrence of component distortion is the thermal expansion behaviour of the materials, in particular of the resin used, which is indicated by coefficients of thermal expansion.
In the prior art, methods exist by which a curing process can be simulated on a computer in such a way that changes to physical properties of this type owing to the curing process can be predicted. Simulation methods of this type are, for example, the CHILE method (CHILE=Curing Hardening Instantaneously Elastic Formulation), the VE method (VE=Visco Elastic) or the PVE method (PVE=Pseudo Visco Elastic). In these methods, the part and its components are divided into three-dimensional (3D) elements having known parameters, and these 3D elements are then subjected to the simulation method, in order to thereby predict the distortion of the part. Owing to the result of the prediction of the distortion of the part, changes in the production method are then carried out in order to thereby arrive accordingly at a part end product having desired physical properties.
The above-described conventional methods deliver relatively good prediction results, as long as only relatively small parts or relatively small portions of parts in the order of a few millimeters are considered. Conventional simulation methods cannot model larger parts, such as the above-mentioned wing shells having a dimension of over 30 meters, in a sufficiently detailed manner owing to a lack of storage capacity, for which there would be an extremely great need. As a result, production of relatively large parts according to the conventional method is considered to be disadvantageous, as a prediction of the distortion of the part is relatively inaccurate, and thus the production of a part having predetermined desired properties is relatively difficult.
In addition, other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.