الفهرس 
English AbstractOnly 14 pages are availabe for public view
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Abstract
The present work aims to study the performance of the valve-less micropump and the parameters affecting its net flow rate. This study is divided into two main parts. The first part concerns with the study of the pulsating flow through a microscale duct and a microscale abrupt area change duct. A simplified analytical solution for the pulsating flow through a microscale straight duct is introduced and this simplified analytical solution of the straight duct is modified to match the pulsating flow through a microscale abrupt area change duct. Also, the numerical results have been used to verify this simplified analytical solution. In the second part, the data extracted from the pulsating flow through a microscale abrupt area change duct has been used to study the effect of various operating conditions and design parameters on the micropump performance. An approximated correlation from the first part was used to predict the net flow rate through the whole micropump. The simulations for the two parts have been conducted using ANSYS Fluent software simulator. The transient laminar flow model was employed to simulate the flow field with interpreting a user defined function (UDF) for pulsating boundary conditions. A complete mesh dependency and time discretization error studies have been introduced to attain mesh and time independence. The net flow rate produced from the pulsating flow through abrupt area change elements has been presented. Also, a correlation for the approximated net flow rate through abrupt area change has been deduced. The operating conditions, design parameters and fluid properties effect on the whole micropump net flow rate have been investigated. The operating frequency was found to be a critical operating parameter. So, the effect of other design and operating conditions on the resonance frequency (optimum operating frequency) has been studied. Moreover, general dimensionless correlation for the micropump performance has been deduced, within the studied range. Thesis objectives: Understanding the physics of pulsating flow through two dimensional ducts. Deduce the net flow rate through the abrupt area change duct. Study the flow through the micropump that incorporates abrupt area change elements rather than the conventional nozzle/diffuser elements. Deduce the net flow rate through the micropump on a clear basis. Study the effect of design and operating parameters on the micropump performance. Compare the conventional micropump that incorporates nozzle/diffuser elements with the studied micropump that incorporates abrupt area change elements.