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العنوان
A Numerical Study On The Effect Of Air Injection On Secondary Flow In A Turbine Cascade \
المؤلف
Omar, Yasser Kamal Hassan
هيئة الاعداد
مشرف / Atef M. Alam El-Din
مشرف / Mohamed El-Ghandour
مناقش / Atef M. Alam El-Deen
مناقش / Gamal Hafez Ahmed, Abd El-hamid
مناقش / Abdoh Abd El-hamid Elagwah
الموضوع
Mechanical Power Engineering.
تاريخ النشر
2018.
عدد الصفحات
208 p. :
اللغة
الإنجليزية
الدرجة
الدكتوراه
التخصص
الهندسة
تاريخ الإجازة
24/12/2018
مكان الإجازة
جامعة بورسعيد - كلية الهندسة ببورسعيد - هندسة القوى الميكانيكية
الفهرس
Only 14 pages are availabe for public view

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Abstract

The secondary flow vortices make the flow field near the endwall highly three-dimensional. The jet-to-secondary flow interaction may help to make an efficient injection arrangement to improve flow characteristics. The injection flow has been investigated widely as an effective way to increase turbine efficiency, So far, but investigations of the influence of individual injection hole inclination angles and mixing injection holes mass flow rates, at various locations, on the blade loading and the aerodynamic losses, have been less found in publications.
In the current study, the interaction between the main flow and injection flow from the flat endwall is analyzed by a numerical simulation. The turbine blade flow passage performance was numerically investigated by ANSYS Fluent commercial code. This manuscript may however include some references still remain within the text (especially in introducing and concluding parts).
The five endwall injection holes were placed at different locations on the typical flat blade cascade with different mixing injection angles and blowing ratios of each individual injection hole. Also, the injection hole diameter was adjusted at four mixing blowing ratios with three different locations.
The new injection arrangement technique has proved its effectiveness in increasing blade loading of 1.85 % more than the baseline blade loading. Also, it proves its effectiveness in suppressing flow losses to loss reduction of 2.1% less than the baseline test case losses, this is achieved by individual change for each hole inclination angle, injection hole mass flow rate, with the injection at blade suction side.
Also, all selected test cases gave positive different readings with respect to the blade loading by creating higher of static pressure on the blade surface and preventing a boundary layer separation at the suction side. Moreover, this modification has a significant effect to create a homogeneous pressure distribution through the blade spanwise direction and hence reducing the large undesirable effects of the secondary flows.