MIXING LOSSES INVESTIGATION DOWNSTREAM OF TURBINE BLADE CASCADE WITH COOLANT FLOW BLOWING

• Main Authors: ASSIM HAMEED YOUSIF, ABASS S. SHRIFFE
• Format: Article
• Language: English
• Published: Taylor's University 2011-04-01
• Series: Journal of Engineering Science and Technology
• Subjects: Mixing losses; Jet injection; Wake; Cascade; Blowing coolant; Five-hole probe
• Online Access: http://jestec.taylors.edu.my/Vol%206%20Issue%202%20April%2011/Vol_6(2)_161_178_Assif%20Yousif.pdf

A major cause of noise and vibration characteristics of turbomachinery has caused by wakes. The characteristics of the wake, the wake decay, the path that it follows, and the mechanisms of mixing losses generated due to the mixing of blade trailing edge cold jet issued into the hot cross flow are important to find adequate solution to the problem. At the present work the wake characteristic was observed by introducing experimental work inside a cascade test rig to investigate the wake domain downstream of blade cascade with the aid of five-hole probe. The case studies were done with cold jets blowing ratios 1.58, 1.667 and 1.935 with jet stream wise angle and jet lateral injection angle 37.5° and 35 º respectively. The measurement showed that there is a certain harmonization in the region of high reverse pressure loss coefficient which reflects the concentration of wake region. Also it was observed three distinct wake regions located in the centre of the passage vortex region. The wake characteristics measurements of the movement path, the growth of wake width, and the physical awareness of the wake propagating may help to explain the mechanisms of mixing losses.