An experimental investigation of heat transfer in narrow, rectangular cooling channels with pin-fins /
The effect of rotation on smooth narrow rectangular channels and narrow rectangular channels with pin-fins is investigated in this study. Pin-fins are commonly used in the narrow sections within the trailing edge of the turbine blade; the pin-fins act as turbulators to enhance internal cooling whil...
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| Format: | Thesis eBook |
| Language: | English |
| Published: |
[Place of publication not identified] :
[publisher not identified] ;
2003.
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| Subjects: | |
| Online Access: | Link to OAKTrust copy |
| Summary: | The effect of rotation on smooth narrow rectangular channels and narrow rectangular channels with pin-fins is investigated in this study. Pin-fins are commonly used in the narrow sections within the trailing edge of the turbine blade; the pin-fins act as turbulators to enhance internal cooling while providing structural support in this narrow section of the blade. The rectangular channel is oriented at 150⁰ with respect to the plane of rotation, and the focus of the study involves narrow channels with aspect ratios of 4:1 and 8:1. The enhancement due to both conducting (copper) pin-fins and non-conducting (plexi-glass) pins is investigated. Due to the varying aspect ratio of the channel, the height-to-diameter ratio (h[p]/D[p]) of the pins varies from two, for an aspect ratio of 4:1, to unity, for an aspect ratio of 8:1. A staggered array of pins with uniform streamwise and spanwise spacing (x[p]/D[p] = s[p]/D[p] = 2.0) is studied. With this array, 42 pin-fins are used, giving a projected surface density of 3.5 pins/in² (0.543 pins/cm²), for the leading or trailing surfaces. The range of flow parameters include Reynolds number (Re[Dh] = 5000-20000), rotation number (Ro = 0.0-0.302), and inlet coolant-to-wall density ratio ([Delta][Ro]/[Ro] = 0.12). Heat transfer in a stationary pin-fin channel can be enhanced up to 3.8 times that of a smooth channel. Rotation enhances the heat transferred from the pin-fin channels 1.5 times that of the stationary pin-fin channels. Overall, rotation enhances the heat transfer from all surfaces in both the smooth and pin-fin channels. Finally, as the rotation number increases, spanwise variation increases in all channels. |
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| Item Description: | "Major subject: Mechanical Engineering". Vita. |
| Physical Description: | xi, 52 leaves : illustrations ; 28 cm. Also available online. Issued also on microfiche from Lange Micrographics. |
| Bibliography: | Includes bibliographical references (leaves 50-51). |