NDLI: Average Passage Flow Field and Deterministic Stresses in the Tip and Hub Regions of a Multi-Stage Turbomachine

Content Provider	The American Society of Mechanical Engineers (ASME) Digital Collection
Author	Uzol, Oguz Chow, Yi-Chih Katz, Joseph Meneveau, Charles
Copyright Year	2003
Abstract	This paper continues our effort to study the dynamics of deterministic stresses in a multistage turbomachine using experimental data. Here we focus on the tip and hub regions and compare them to mid span data obtained in previous studies. The analysis is based on data obtained in PIV measurements performed in the second stage of a two-stage turbomachine. A complete data set is obtained using blades and fluid with matched optical index of refraction. Previous measurements at mid span have shown that at mid span and close to design conditions, the deterministic kinetic energy is smaller than the turbulent kinetic energy. The primary contributor to the deterministic stresses at mid span is the interaction of a blade with the upstream wakes. Conversely, we find that the tip vortex is the dominant source of phase-dependent unsteadiness and deterministic stresses in the tip region. Along the trajectory of the tip vortex, the deterministic kinetic energy levels are more than one order of magnitude higher than the levels measured in the hub and mid-span, and are of the same order of magnitude as the turbulent kinetic energy levels. Reasons for this trend are explained using a sample distribution of phase-averaged flow variables. Outside of the region affected by tip vortex transport, within the rotor-stator gap and within the stator passages, the turbulent kinetic energy is still 3–4 times higher than the deterministic kinetic energy. The deterministic and turbulent shear stress levels are comparable in all spanwise locations, except for the wakes of the stator blades, where the turbulent stresses are higher. However, along the direction of tip vortex transport, the deterministic shear stresses are about an order of magnitude higher than the turbulent shear stresses. The decay rates of deterministic kinetic energy in the hub and mid-span regions are comparable to each other, whereas at the tip, the decay rate is higher. The decay rates of turbulent kinetic energy are much smaller than those of the deterministic kinetic energy. The paper also examines terms in the deterministic kinetic energy transport equation. The data indicate that “Deterministic Production” and a new term, called here “Dissipation due to Turbulence” are the dominant source/sink terms. Regions with alternating signs of Deterministic Production indicate that the energy transfer between the phase-averaged and average-passage flow fields can occur in both directions. The divergence of the Pressure-Velocity correlation, obtained from a balance of all the other terms, is dominant and appears to be much larger than the deterministic production (source/sink) term. This trend indicates that there are substantial deterministic pressure fluctuations in the flow field, especially within the rotor-stator gap and within the stator passage.
Sponsorship	International Gas Turbine Institute
Starting Page	975
Ending Page	988
Page Count	14
File Format	PDF
ISBN	0791836894
DOI	10.1115/GT2003-38598
e-ISBN	0791836711
Volume Number	Volume 6: Turbo Expo 2003, Parts A and B
Conference Proceedings	ASME Turbo Expo 2003, collocated with the 2003 International Joint Power Generation Conference
Language	English
Publisher Date	2003-06-16
Publisher Place	Atlanta, Georgia, USA
Access Restriction	Subscribed
Subject Keyword	Turbulence Blades Wake turbulence Rotors Refractive index Turbomachinery Flow (dynamics) Pressure Stress Design Energy transformation Fluids Dynamics (mechanics) Energy dissipation Stators Shear stress Wakes Fluctuations (physics) Trajectories (physics) Kinetic energy
Content Type	Text
Resource Type	Article

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in