In this blog post, we provide you with some tips on how to make your Simcenter Amesim models run faster.<\/P><\/p>\n This can be done through the following best practices:<\/P> Implicit variables are generated by the solver whenever there is an algebraic loop<\/STRONG> in the system. An algebraic loop occurs when there is no order in which the submodels can be called such that all the inputs of each submodel are known when the submodel is called.<\/P> Example: ? = (?, ?)<\/P><\/p>\n The solution to remove an implicit loop can be to include a time constant within the loop (inertia, first order lag, inductor \u2026) or to remove the calculation of the variable generating the algebraic loop.<\/P> The computation time is directly impacted by the number of states N. For a standard problem to solve within Simcenter Amesim, Adams’ method is used where CPU = k*N. When backward differential formulae method is used, CPU=k1*N + k2*N\u00b2.<\/P><\/p>\n The solution to reduce the number of states variables is to group hydraulic volumes, mechanical masses or electric resistances<\/STRONG>.<\/P> Usually, the higher the tolerance of the integrator is, the higher the simulation time is. The solution is to minimize the tolerance parameter<\/STRONG> without compromising the simulation results accuracy.<\/P> A discontinuity appears when a variable is suddenly jumping from one value to another (switch from laminar to turbulent flow, friction stick-slip, hysteresis\u2026). This causes a restart of the solver to manage the interpolation between the two values. The solution for avoiding useless discontinuities can be to disable the discontinuity handling<\/STRONG> of tabulated submodels (when possible) or to add damping<\/STRONG>.<\/P> Simulation results are written in a data file all along the simulation and by default all submodels variables are saved (the frequency of the results saving is set by the user in Run Parameters\u2019 Print interval). The solution for reducing the number of saved data is either to save only the required variables<\/STRONG> or to increase the print interval<\/STRONG> (for the complete simulation or dynamically during the simulation).<\/P> Maps imported from experimental data can typically be quite noisy or contain discontinuities. The solution to properly condition your maps is either to disable the discontinuity handling<\/STRONG>, use an appropriate data sample<\/STRONG> or filter the noisy signals<\/STRONG>.<\/P> Most of the information above are explained in the infographic<\/A> below, for the particular case of reaching real-time capacity:<\/P>![\"Make-your-Simcenter-Amesim-model-real-time-compatible.jpg\"](\"http:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2019\/09\/Make-your-Simcenter-Amesim-model-real-time-compatible-4.jpg\" "\\"Make-your-Simcenter-Amesim-model-real-time-compatible.jpg\\"")
<\/span>This statement perfectly highlights the challenge of choosing the right level of modeling \/ assumptions when starting a new simulation study. It is particularly true when you want to reach real-time capability for doing virtual sensing<\/STRONG>, IIOT on edge<\/STRONG>, model-based system testing<\/STRONG> or simply want to have your model running faster<\/STRONG>.<\/P><\/p>\n
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\nAvoid generating implicit variables<\/H2>
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\n![\"Simcenter-Amesim-model-reduction1.png\"](\"http:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2019\/09\/Simcenter-Amesim-model-reduction1-1.png\" "\\"Simcenter-Amesim-model-reduction1.png\\"")
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\nAvoid useless states variables
![\"Simcenter-Amesim-model-reduction2.png\"](\"http:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2019\/09\/Simcenter-Amesim-model-reduction2-1.png\" "\\"Simcenter-Amesim-model-reduction2.png\\"")
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\nDefine the best run parameters<\/H2>
\n![\"Simcenter-Amesim-model-reduction3.png\"](\"http:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2019\/09\/Simcenter-Amesim-model-reduction3-1.png\" "\\"Simcenter-Amesim-model-reduction3.png\\"")
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\n <\/H2>
\nAvoid useless discontinuities<\/H2>
\n![\"Simcenter-Amesim-model-reduction4.png\"](\"http:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2019\/09\/Simcenter-Amesim-model-reduction4-1.png\" "\\"Simcenter-Amesim-model-reduction4.png\\"")
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\nSave only useful variables<\/H2>
\n![\"Simcenter-Amesim-model-reduction5.png\"](\"http:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2019\/09\/Simcenter-Amesim-model-reduction5-1.png\" "\\"Simcenter-Amesim-model-reduction5.png\\"")
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\nCondition correctly your maps<\/H2>
\n![\"Simcenter-Amesim-model-reduction6.png\"](\"http:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2019\/09\/Simcenter-Amesim-model-reduction6-1.png\" "\\"Simcenter-Amesim-model-reduction6.png\\"")
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\n![\"Simcenter-Amesim-model-reduction7.png\"](\"http:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2019\/09\/Simcenter-Amesim-model-reduction7-1.png\" "\\"Simcenter-Amesim-model-reduction7.png\\"")
<\/span><\/P><\/p>\n <\/H2>
\nPrint out our step-by-step process <\/H2>
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![\"Make-your-Simcenter-Amesim-model-real-time-compatible-infographic.png\"](\"http:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2019\/09\/Make-your-Simcenter-Amesim-model-real-time-compatible-infographic-1.png\" "\\"Make-your-Simcenter-Amesim-model-real-time-compatible-infographic.png\\"")
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