Dynamic analysis solution
I agree entirely with the comments made by Mr Nordell and emphasise that in order to get a proper solution and accurate dynamic analysis results the methods used must:
1. Determine the conveyor friction factors based on the belt tensions at the particular time step in the analysis. The conveyor frictions / resistances change depending on the belt tensions and belt sag in the system at each time step (and at each idler) during starting or stopping and if your algorithm does not take this into account the results will not be accurate. Assumptions based on merely using a "High" or "Low" global friction factor will not give accurate results.
2. It is necessary to use the forward predictor Runge-Kutta algorithms in order to obtain accurate solutions. If the fixed step Runge Kutta methods are used the solution can be found for very flexible belts such as fabric belts, however large conveyors use steel reinforced belts and the high forces required to induce relatively small strains in the belt require a very accurate solution and the adaptive Runge-Kutta methods which estimate the truncation errors and adjust the step size accordingly are essential for a good solution. The Dormand-Prince method is one such method and is utilised in the Helix delta-T software.
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