BiographyWiden TabakoffProfessor of Aerospace Engineering

& Engineering Mechanics

Director, Erosion and Turbomachinery Performance Deterioration Laboratory

Fellow of the AIAA, ASME and University of Cincinnati

DegreePhD (Dr.Ing.), 1945, University of Berlin

Contact745 Baldwin HallP.O. Box 210070Cincinnati, OH 45221-0070Phone: (513) 556-3226Fax: (513) 556-5038Email: Widen.Tabakoff@uc.edu

Clients Associated with the University of Cincinnati’s Turbomachinery Erosion Laboratory

General ElectricAllison Rolls-RoyceSiemens WestinghousePratt & WhitneyHoneywellUnited Air LinesLufthansaSulzer MetcoFergusonExxon MobilCorningSermatechPraxAir

SurmetChromalloyIngersoll RandTexacoDupontUS Navy AirUS Air ForceUS ArmyUS Department of EnergyNASAArgonne National Laboratory

Highlights of Gas Turbine Erosion Research at the University of Cincinnati

TheoreticalFlow & particle dynamics modeling

Blade surface erosion predictions

Performance Loss

Performance Retention

Experimental

• Particle surface interactions

Blade & seal material erosion

Particle restitution characteristics (LDV)

• Coating life evaluation

• Turbomachinery performance loss

Instantaneous

Permanent (erosion)

Engine Performance Deterioration

The particles may be from an environment such as volcanic ash, sand, and chemical substances such as particles formed by fuel combustion. The particles contained in the flow through the engine can be erosive or non-erosive. Both will affect turbomachinery performance during ingestion; however, the non-erosive particle influence will be temporary, whereas the erosive particle influence will produce permanent engine performance loss.

JT9D 9th Stage HPC Rotor Comparison

Erosion Wind Tunnel

The high temperature erosion tests were conducted in the UC erosion rig, which was designed to provide erosion data in the range of operating temperatures experienced in compressors and turbines. In addition to temperature, the facility properly simulates all the erosion parameters which were determined to have an impact on aerodynamics, including particle velocity, angle of impact, particle size, particle concentration, and sample size.Particle Rebound Wind Tunnel

Facilities

Hot Erosion Wind Tunnel

Cascade Erosion TunnelCompressor Test Facility

Turbine Test Facility

Schematic of Erosion Test Facility

Rebound Test Facility

Hot Erosion Wind Tunnel

UC’s high temperature erosion tunnel rig simulates particle surface interactions at operating conditions in compressors and turbines

– Temperatures (ambient – 2000oF)

– Impact velocities (60-1800 ft/sec)

– Impingement angles (0o – 90o)

– Particles and target materials (various)

– Particle loading (various)

UC’s T-53 G Compressor

Compressor rotor Compressor stator

Multistage compressor

UC’s T-53 G Compressor

Schematic of Compressor Test Facility

Schematic of Turbine Test Facility

Schematic of specimen and holder

Sample ID Angle/Deg Wi/(g) Wf/(g) del W/(mg) Qp/(g) Erosion/(mg/g)

1 TiN 15 4.8353 4.8351 0.0002 10 0.02

2 TiN 30 4.814 4.814 0.0004 10 0.04

3 TiN 45 5.037 5.0364 0.0006 10 0.06

4 TiN 60 4.4569 4.4554 0.0014 10 0.14

5 TiN 90 4.8489 4.8469 0.002 10 0.2

Wi = initial weight (g) ∆W = Wi – Wf (mg) 0.000

Wf = sample weight after testing (g) Qp = particle weight impacting the tested sample (g)

Test conditionsTest Conditions: T=1300 F, V=1000ft/sec

Particle: Arizona Test Dust (20 microns)Samples: (TiN) coating

The erosion rate (ε) was determined for each test sample from the following relation

εw = Erosion rate by weight = change in mass of sample =

mass of impacting particles

εv = Erosion rate by volume = change in volume =

mass of impacting particles

2areagmg

2

3

areagcm

Erosion rate prediction

Subtract the tested sample weight after erosion from the initial sample weight to obtain ∆W = weight loss.

To convert the weight loss ∆W in volume

loss ∆V, divide ∆W by the density ρ of the coating: or

Qp = total dose on the specimen impact.

gcmQ

V

pv /3=∆=ε gmg

Q

W

pw /=∆=ε

Effect of impingement angle on erosion rate variation on M-246 substrate and RT22B coatings (T=815oC, Vp=366 m/s, Fly Ash particles)

Compressor cascade

Erosion weight loss for compressor blades.

Compressor rotor and graphs