The paper presents the two-phase model to describe blood flow in large and in small blood vessels. Based on this model the study gives an explanation for long known features (effects) of blood flow in the vessels: dependence of the hematocrit (packed cell volume) on the diameter of the vessel, existence of cell-free plasma layer near the vessel wall, obtuse (as compared with the profile of Poiseuille flow) velocity profile of a blood; dependence of the blood viscosity on the diameter of the vessel. The researcher determines dependences of the blood rate and viscosity on the diameter of a blood vessel. With the flow of blood in small vessels (less than 200 μm), the rheological properties of the blood depend on the size of the vessel - the apparent viscosity of the blood drops with a decrease in the diameter of the blood vessel. To describe the flow of blood in small vessels, it is necessary to create an equation of state that depends (apart from other parameters) on the diameter of the vessel.
Ushbu maqolada katta qon tomirlarida qon oqimini tavsiflash uchun ikki fazli modelni taqdim etilgan. Ushbu modeldagi tadqiqotlar tomirlarda qon oqimining ma'lum xususiyatlariga (oqibatlariga) izoh beradi: gematokritning (paketlangan hujayra hajmining) tomirning diametriga bog'liqligi, tomir devorining yaqinida hujayra bo'sh plazmasi qatlami mavjudligi , qonning tezligi qon tomirningning diametriga bog'liqligi. Tadqiqotchi qon harakati o´zgarishi qon tomirlarining diametriga bog'liqligini aniqlaydi. Kichik tomirlarda qon oqimi (200 mikrondan kam) bilan qonning reologik xususiyatlari tomir kattaligiga bog'liq - qon tomirlarining diametrini pasayishi bilan qonning harakati o´zgarishi matematik usulda ko´rsatilgan. Kichik tomirlarda qon oqimini tavsiflash uchun tomir diametri bo'yicha boshqa parametrlarga bog'liq bo'lgan qon tenglamasini yaratishdan iborat.
В статье представлена двухфазная модель для описания кровотока в больших и малых кровеносных сосудах. На основе этой модели исследование дает объяснение давно известных признаков (эффектов) кровотока в сосудах: зависимость гематокрита (объем упакованной ячейки) от диаметра сосуда, наличие бесклеточного плазменного слоя вблизи стенки сосуда , тупые (по сравнению с профилем потока Пуазейля) профиль скорости крови; зависимость вязкости крови от диаметра сосуда.Исследователь определяет зависимости скорости крови и вязкости от диаметра кровеносного сосуда. При потоке крови в небольших сосудах (менее 200 мкм) реологические свойства крови зависят от размера сосуда - кажущаяся вязкость капель крови с уменьшением диаметра кровеносного сосуда. Чтобы описать поток крови в малых сосудах, необходимо создать уравнение состояния, которое зависит (помимо других параметров) от диаметра сосуда.
The paper presents the two-phase model to describe blood flow in large and in small blood vessels. Based on this model the study gives an explanation for long known features (effects) of blood flow in the vessels: dependence of the hematocrit (packed cell volume) on the diameter of the vessel, existence of cell-free plasma layer near the vessel wall, obtuse (as compared with the profile of Poiseuille flow) velocity profile of a blood; dependence of the blood viscosity on the diameter of the vessel. The researcher determines dependences of the blood rate and viscosity on the diameter of a blood vessel. With the flow of blood in small vessels (less than 200 μm), the rheological properties of the blood depend on the size of the vessel - the apparent viscosity of the blood drops with a decrease in the diameter of the blood vessel. To describe the flow of blood in small vessels, it is necessary to create an equation of state that depends (apart from other parameters) on the diameter of the vessel.
| № | Муаллифнинг исми | Лавозими | Ташкилот номи |
|---|---|---|---|
| 1 | Khujatov N.J. | PhD student of Urgench State University | UrDU |
| 2 | Joao O.V. | Professor of Porto University | UrDU |
| № | Ҳавола номи |
|---|---|
| 1 | Pries A.R., Secomb T.W. Blood flow in microvascular networks // Handbook of Physiology: Microcirculation / ed. R.F. Tuma, W.N. Dura, K. Ley. – Academ Press, 2008. |
| 2 | Sharan M., Popel A.S. A two-phase model for flow of blood in narrow tubes with increased effective viscosity near the wall // Biorheology. – 2001. – Vol. 38. |
| 3 | Long D.S., Smith M.L., Pries A.R. et al. Micro-viscometry reveals reduced blood viscosity and altered shear rate and shear stress profiles in microvessels after hemo-dilution // Proc. Natl. – Acad. Sci. USA. 2004. – Vol. 101, ?27 |