Experimental and computational investigation of the flow field inside an axial fan /
Turbomachinery is used in a variety of engineering applications such as power generation and pumping. The need to reduce operating costs drives the effort to improve the efficiency of these machines. Improving the efficiency of turbomachinery requires understanding the flow phenomena which occur w...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
2002.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=765073101&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | Turbomachinery is used in a variety of engineering applications such as power generation and pumping. The need to reduce operating costs drives the effort to improve the efficiency of these machines. Improving the efficiency of turbomachinery requires understanding the flow phenomena which occur within the rotating equipment. This work focuses on the measurement of the flow field at mid-span inside an axial fan using a Laser Doppler Velocimeter (LDV). The flow field is measured from the trailing edge of the first stator blade, through the rotor blade to the leading edge of the second stator blade. The flow field inside the axial fan is simulated in a commercial Computational Fluid Dynamics (CFD) code CFX-TASCflow. The simulation models the first stage of the axial fan using three stator blades and two rotor blades. The full three dimensional flow field was calculated and the mid-span results compared to the measured results. The development of a two-component Doppler Global Velocimetry (DGV) system including both hardware, data acquisition, and data reduction software is also described. This nonintusive optical measurement system is an emerging whole-field measurement technique based on the Doppler shifting of light reflected by seed particles in a flow field. Determination of this Doppler shift is done by using a frequency-to-intensity image converter in the form of a laser line absorption (ALF) cell containing molecular iodine vapor. The frequency shift imparted to the light scattered by moving seed particles is then used to determine the velocity. For each viewing angle, one component of the velocity can be measured. A laser is used to illuminate a two-dimensional plane in the flow field. For a two-component DGV, this plane is observed from two angles. Depending on the viewing angle, either a component in the illumination plane and one perpendicular to it can be measured or both components in the illumination plane can be measured if one can assume the third component is negligible. |
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| Item Description: | Vita. "Major Subject: Mechanical Engineering". |
| Physical Description: | x, 123 leaves : illustrations ; 28 cm. + 1 CD ROM. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references (leaves 86-90). |