Improvement of engineering methodology of design of shell-and-tube heat exchangers in MathCad mathematical systemA. R. Lebedev, V. V. Romanov, N. S. Alekhin, S. O. Kireev and G. A. GalkaE3S Web Conf., 592 (2024) 03017DOI: https://doi.org/10.1051/e3sconf/202459203017