Experimental Investigation of Additional Loss Associated With Incoming Wakes in Low-Pressure Turbine CascadesSource: Journal of Turbomachinery:;2024:;volume( 146 ):;issue: 005::page 51013-1DOI: 10.1115/1.4064318Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: The present paper aims to experimentally investigate the influence of wake-passing frequency, Reynolds number, and suction surface diffusion rate on the additional loss due to incoming wakes to the profile loss in the low-pressure turbine (LPT) cascades and discuss a design guide for reducing the additional loss. Using a moving-bar mechanism, the unsteady effects of incoming wakes were measured in a low-speed linear turbine cascade facility. The wake-passing frequency was varied by adjusting the moving-bar speed. The different airfoils with different surface velocity distributions were tested to examine the effect of suction surface diffusion rate. For each test case in an unsteady flow condition, the additional loss due to incoming wakes was derived by subtracting the profile loss from the measured total pressure loss across the cascade. Here, the profile loss was estimated by using the friction drag force, which was calculated by the measured surface velocity distribution, and the pressure drag force, which was calculated by the measured surface pressure distribution and the predicted base pressure. The resultant additional loss includes all kinds of losses associated with incoming wakes, such as mixing loss of incoming wakes enhanced in the blade passage and unsteady interaction loss between incoming wakes and surface boundary layers. It was demonstrated that in an unsteady flow condition, a substantial performance improvement was obtained in the entire Reynolds number range by applying the surface velocity distribution with no laminar separation to a low-solidity blade row.
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contributor author | Kodama, Hidekazu | |
contributor author | Funazaki, Ken-ichi | |
date accessioned | 2024-04-24T22:50:45Z | |
date available | 2024-04-24T22:50:45Z | |
date copyright | 1/16/2024 12:00:00 AM | |
date issued | 2024 | |
identifier issn | 0889-504X | |
identifier other | turbo_146_5_051013.pdf | |
identifier uri | http://yetl.yabesh.ir/yetl1/handle/yetl/4295974 | |
description abstract | The present paper aims to experimentally investigate the influence of wake-passing frequency, Reynolds number, and suction surface diffusion rate on the additional loss due to incoming wakes to the profile loss in the low-pressure turbine (LPT) cascades and discuss a design guide for reducing the additional loss. Using a moving-bar mechanism, the unsteady effects of incoming wakes were measured in a low-speed linear turbine cascade facility. The wake-passing frequency was varied by adjusting the moving-bar speed. The different airfoils with different surface velocity distributions were tested to examine the effect of suction surface diffusion rate. For each test case in an unsteady flow condition, the additional loss due to incoming wakes was derived by subtracting the profile loss from the measured total pressure loss across the cascade. Here, the profile loss was estimated by using the friction drag force, which was calculated by the measured surface velocity distribution, and the pressure drag force, which was calculated by the measured surface pressure distribution and the predicted base pressure. The resultant additional loss includes all kinds of losses associated with incoming wakes, such as mixing loss of incoming wakes enhanced in the blade passage and unsteady interaction loss between incoming wakes and surface boundary layers. It was demonstrated that in an unsteady flow condition, a substantial performance improvement was obtained in the entire Reynolds number range by applying the surface velocity distribution with no laminar separation to a low-solidity blade row. | |
publisher | The American Society of Mechanical Engineers (ASME) | |
title | Experimental Investigation of Additional Loss Associated With Incoming Wakes in Low-Pressure Turbine Cascades | |
type | Journal Paper | |
journal volume | 146 | |
journal issue | 5 | |
journal title | Journal of Turbomachinery | |
identifier doi | 10.1115/1.4064318 | |
journal fristpage | 51013-1 | |
journal lastpage | 51013-9 | |
page | 9 | |
tree | Journal of Turbomachinery:;2024:;volume( 146 ):;issue: 005 | |
contenttype | Fulltext |