# Time Step for Numerically Solving Parabolic Problems

## Abstract

This work deals with the problem of choosing a time step for the numerical solution of boundary value problems for parabolic equations. The problem solution is derived using the fully implicit scheme, whereas a time step is selected via explicit calculations. Using the explicit scheme, we calculate the solution at a new time level. We employ this solution in order to obtain the solution at the previous time level (the implicit scheme, explicit calculations). This solution should be close to the solution of our problem at this time level with a prescribed accuracy. Such an algorithm leads to explicit formulas for the calculation of the time step and takes into account both the dynamics of the problem solution and changes in coefficients of the equation and in its right-hand side.

## Notes

### Acknowledgements

This work was supported by RFBR (project 14-01-00785).

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