﻿.. _limiters1:

.. index:: Ограничители для расчета миграции

=================================================
Ограничители потоков ( расчет миграции )
=================================================

Пользователь может выбрать для расчета миграции один из следующих 
ограничителей потока

+----------------------------+--------------------------------------------------------------------------+
|  Ограничитель              |     Формула                                                              |
+============================+==========================================================================+
|  Zero                      |     0.0                                                                  |
+----------------------------+--------------------------------------------------------------------------+
|  Van Leer                  |     :math:`(r + |r|)/(1+ |r|)`                                           |
+----------------------------+--------------------------------------------------------------------------+
|  Van Albada                |     :math:`(r + r^2)/(1+ r^2)`                                           |
+----------------------------+--------------------------------------------------------------------------+
|  Min-Mod                   |     :math:`max(0, min(r,1))`                                             | 
+----------------------------+--------------------------------------------------------------------------+
|  SuperBee                  |     :math:`max(0, min(2r,1), min(r, 2))`                                 |
+----------------------------+--------------------------------------------------------------------------+
|  Quick                     |     :math:`max(0, min(2r, \frac{1}{4} (3+r), 2))`                        |
+----------------------------+--------------------------------------------------------------------------+
|  Umist                     |     :math:`max(0, min(2r,\frac{1}{4} (1+3r)), \frac{1}{4} (3+r), 2 )`    |
+----------------------------+--------------------------------------------------------------------------+
|  Muscl                     |     :math:`max(0, min(2,2r, \frac{1}{2} (1+r) ) )`                       |
+----------------------------+--------------------------------------------------------------------------+
|  Venkatakrishnan           |     :math:`\frac{r^2+2r}{r^2+r+2}`                                       |
+----------------------------+--------------------------------------------------------------------------+
