Project Results

Reduced Order Models

The overall result expected by the project is the development of a high-fidelity reduced-order model able to simulate, under varying load and velocity, the dynamical behaviour of high-performance gear pairs and to evaluate the noise generated and radiated by such gears. These results will be measured by comparing key performance indexes (e.g. the Transmission Error, the vibration amplitude and the sound pressure level at specific location) obtained by proposed models and experimental results. For selected cases, the proposed models’ numerical complexity will also be compared with FEM simulations proposed by the scientific literature. Many control parameters will be used to assess and evaluate the models, the first being the TE, that can be computed by the numerical models and compared with experimentally measured ones. Multibody models will allow the computation of the TE for each case study, both in quasi-static and dynamic conditions, at different rotational speeds and under several load conditions.

Dynamic Load Amplification Factor

Dynamic load amplification factor (DLAF) and nonlinear jump phenomena will be computed considering the system both in acceleration and deceleration conditions. Other kinematical, dynamical and structural parameters (this last being computed for component mode models only), can be extrapolated from the models if needed.

Epistemic Uncertainty

The Epistemic Uncertainty model will be used to evaluate the effect of the multibody parameters, represented as fuzzy numbers, on the analysed performance. In this context, results from the model are not single values but rather graded intervals function of the operational parameters (e.g. load, velocity), and therefore the assessment of the results (e.g. the TE) will be evaluated in terms of inclusion within the Epistemic Uncertainty result of all the measured TE, for different operating conditions.

Acoustic Model

The acoustic model will compute the sound pressure level of all the significant surfaces, with acoustic power and sound pressure level representing the main parameter of interest. They too will be computed at different rotational speeds and under several load conditions, and the influence of the characteristics of the contact surfaces will be evaluated in terms of acoustic emission.


The last aim of this project is the validation of models through experiments. The parameters needed for the validation (TE, vibration, and acoustic power) will be periodically recorded at each run. A threshold value will be set to evaluate the simulations: if the output of the numerical models will overlap those from the experiments for more than 90%, then the models will pass the evaluation.