20.500.12556/RUL-144242 Navier-Stokes solutions for accelerating pipe flow a review of analytical models This paper reviews analytical solutions for the accelerated flow of an incompressible Newtonian fluid in a pipeline. This problem can be solved in one of two ways according to the (1) imposed pressure gradient or (2) flow rate. Laminar accelerated flow solutions presented in a number of publications concern cases where the two driving mechanisms are described by simple mathematical functions: (a) impulsive change; (b) constant change; (c) ramp change, etc. The adoption of a more complex and realistic description of the pressure gradient or flow rate will be associated with a profound mathematical complexity of the final solution. This is particularly visible with the help of the universal formula derived by several researchers over the years and discussed in this paper. In addition to the solutions strictly defined for laminar flow, an interesting extension of this theory is the theory of underlying laminar flow for the analysis of turbulent accelerated pipe flows (TULF model developed by García García and Alvariño). The TULF model extends the Pai model developed more than 60 years ago, which has been previously used for steady flows only. The discussed solutions extend the theory of analytical solutions of simplified two-dimensional Navier–Stokes equations and can be used not only to study the behavior of liquids during accelerating pipe flow but they can also be used to test the accuracy of commercial CFD codes. Navier–Stokes equations analytical solutions accelerated flow pipe flow Navier-Stoksove enačbe analitične rešitve pospešujoč tok cevni tok kanalski tok true false true Angleški jezik Slovenski jezik Članek v reviji 2023-02-06 11:46:04 2023-02-06 11:46:12 2023-02-07 03:42:51 0000-00-00 00:00:00 2023 0 0 30 str. iss. 3, art. 1407 Vol. 16 Jan. 2023 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.22 1996-1073 10.3390/en16031407 140793091 Urbanowicz_...-Navier-Stokes_solutions_for_accelerating_pipe_flow—a_review_of_analytical_models.pdf Urbanowicz_...-Navier-Stokes_solutions_for_accelerating_pipe_flow—a_review_of_analytical_models.pdf 1 278F54D388D14692DB2C2F9B7447C0AA 5aa43d66139280ee09abc2e1c4fb5b10cabb4f3891957d0f0f37201be6ade8e2 9bfb07e3-a60b-11ed-9c94-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=166448 https://www.mdpi.com/1996-1073/16/3/1407 1 2d7b3c15-a60b-11ed-9c94-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=166447 Fakulteta za strojništvo 0 0 0