Assessment of beam modeling methods for rotor blade applications

There is no lack of composite beam theories. Quite to the contrary, there might be too many of them. Different approaches, notation, etc., are used by the authors of those theories, so it is not always straightforward to compare the assumptions made and to assess the quantitative consequences of those assumptions. Moreover, there is a serious lack of experimental results and benchmark problems. As a result, one finds that most theories perform about equally well on the few extant benchmark problems. This can obscure differences among theories and simultaneously create the false expectation that a specific theory will perform as well in all cases. The goal of this paper is to attempt to objectively assess theories within a common framework. The validity and relative importance of various assumptions that are present in the literature are discussed. It is hoped that this will be a first step toward the clearly desirable situation in which an engineer can safely and easily choose a composite beam theory based on the type of application and specific needs for fidelity.