Lunch and Learn Presentation FTT-UCF Impingement Testing Roberto Claretti UTSR Fellow - Heat Transfer Intern Florida Turbine Technologies, Inc. RClaretti@fttinc.com www.fttinc.com
Who am I? My name is Roberto Claretti, Graduated from UCF with a BSME in 2011 I am a Department of Energy University Turbine Systems Research Fellow I am a Masters in Mechanical Engineering Student in the Thermofluids Track I have worked for the past three years at the Center for Advanced Turbomachinery and Energy Research located at the Siemens Energy Center in Orlando I have worked on numerous types of heat transfer and flow tests; they include: Film Cooling Near Wall Cooling Impingement Cooling (Honors in Major Thesis) Coupled Impingement/Effusion Cooling I have also worked with CFD using Gambit and Fluent 2
Overview of Summer Accomplishments Designed, Procured, Built, Tested and Performed Data Reduction on A Special Impingement Heat Transfer Test Article. Designed and Procured a Seal Test Rig Acquired and post processed flow data 3
Other things I learned The Boeing 777, powered by two GE90 s, burns 3.9 gallons of fuel every second! The energy transfer rate of a gas pump pumping 10 gallons a minute is equivalent to 21 MW! The same pump has the ability to earn $2200 an hour! Two orders of magnitude more than me! This 8000 gallon gas tanker truck filled with gasoline can power the average American home for 15 years! (with an energy conversion efficiency of 60%, CCGT) 4
Impingement Heat Transfer Test We were able to design, machine, assemble and test a heat transfer experiment to better understand the convective characteristics of four test setups: Smooth Channel Validation Impingement Validation Case B 5
Design of Parts All parts were made out of acrylic, 2D drawings were cut by a, in-house, 3 axis CNC Diffuser was made with polystyrene cut using an electrically heated wire Typical measured accuracy ±0.010 in for non critical dimensions, ±0.006 in for critical dimensions (diameter) 6
Heat Transfer Background Newton s Law of Cooling 7
Temperature Sensitive Paint Image of TSP taken without low pass filter using regular camera TSP is in the center, everything seems to glow in a blue color Reference Image Test Image Image of TSP taken with the lowpass filter using regular camera TSP is seen to glow compared to the rest of the test section. This happens due to the TSP emitting light of a lower wavelength that gets picked up by the scientific grade CCD camera. Pictures taken with the CCD are shown on the right 8
Heat Transfer Test Setup Heaters and side walls are attached to the surface Jet Plate is bolted to the test section Thermocouples are attached to the inlet of the jet plate Thermocouples that measure coolant temperature are shown 9
Heat Transfer Test Setup Channel exit diffuser Pressure tap lines Thermocouple Heater Strips TSP Lead Wires 10
Impingement Test Setup Piping running through the ceiling Venturi Flow meter Handheld Manometer Blower under suction Flow metering valve Test Section 11
Smooth Channel Validation A smooth channel case was tested by blocking the holes of one of the jet plates z x The hydraulic diameter was decreased by attaching a spacer to the wall opposite of the heaters An entrance region of L=23D h was attached to the channel in order to have a semideveloped momentum BL before the start of the thermal BL Channel dimensions: D h =.L heated /D h =20 Three Reynolds numbers were run: 60k, 41k and 23k 12
Smooth Channel Validation Laterally Averaged Nu/Nu DB Re = 60,000 Re = 41,000 Re = 23,000 Nu/Nu DB 0 2 4 6 8 10 12 14 16 18 20 x/d h 13
Impingement Validation Case Case z/d x/d x c /D N x y/d y c /D N y Validation 3 3 63 20 8 32 4 y/d x/d z y z/d x Heated Area 14
Impingement Validation Nu Profiles Nu y Re j =16,000 Nu y x Re j =13,000 y Re j =10,000 x z x 15
Case A Case z/d x/d N x y/d N y y c /D y s /D h/d x c /D L/D Re javg B 3 3.0 20 3 4 32 13 0 63 1 17000 x/d y/d y s /D z y z/d x Heated Area 16
Case A Local Nu Profiles Nu y Re j =16,000 y Re j =13,000 y Re j =10,000 x z x 17
Nu Case A Laterally Averaged Nu Case A Nu values increase as x increases contradicting Florschuetz predictions Amplitude of fluctuations in Nu remain constant throughout implying little effect of crossflow 18
log Nu Impingement Scheme Comparison Taking log of both sides Case A and impingement validation have similar m. The Florschuetz prediction with these geometric parameters is m=0.68 which matches closely with both Case A and Impingement Validation. 19
Thank You! Now FTT has the necessary data to design components that utilize any of these cooling setups with confidence I would like to thank Jim Downs, Gloria Goebel, Bryan Bernier, Michelle Valentino, An Lee, Ken Landis and everyone else at FTT for their kind hospitality and for teaching me more about gas turbine heat transfer! I would also like to thank the DoE and UTSR Gas Turbine Industrial Fellowship Program for giving me this great opportunity! 20