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General Disclaimer One Or More of the Following Statements May Affect General Disclaimer One or more of the Following Statements may affect this Document This document has been reproduced from the best copy furnished by the organizational source. It is being released in the interest of making available as much information as possible. This document may contain data, which exceeds the sheet parameters. It was furnished in this condition by the organizational source and is the best copy available. This document may contain tone-on-tone or color graphs, charts and/or pictures, which have been reproduced in black and white. This document is paginated as submitted by the original source. Portions of this document are not fully legible due to the historical nature of some of the material. However, it is the best reproduction available from the original submission. Produced by the NASA Center for Aerospace Information (CASI) " I ASA CR-72458 Allison EDR 5996 Quiet Engine Definition Program Prepared for NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACT NAS3-10496 ^'^ r ^ MAY 1969 u>1j I n7^ a a O 1, w REC'E<IYEO ^> U NASAS I F^^A^C.,i,t^"^Y W m I Allison Division • General Motors 2 ,M to V ^ Indianapolis, Indiana p (lC 6 ^ 1' W O U a < z Too ,.OA A11110VA W, NASA CR -72458 Allison EDR 5996 Final Report Quiet Engine Definition Program Prepared for NATIONAL AERONAUTICS AND 40ACE ADMINISTRATION September 19, 1968 CONTRACT NAS3-10496 Technical Management NASA-Lewis Research Center Cleveland, Ohio Propulsion Systems Acoustics Branch J. J. Kramer J. F. McBride Allison Division • General Motors Indianapolis, Indiana QUIET ENGINE DEFINITION PROGRAM FINAL REPORT ABSTRACT The Quiet Engine Definition Program consisted of a study of the design characteristics and noise production of engines in the bypass ratio range of 3 to 8. A preliminary design was made for an engine having a bypass ratio of 5. 5. This engine is rated at 4900-1b (21. 8-kN) cruise thrust at 35, 000 ft (10. 7 km) at Mach 0.82. The specific fuel consumption is 0. 627 lbf/ hr/lbt (0.017 7 g/N-sec). The engine weight is 4780 lb (2168 kg), the fan tip diameter is 74 in. (1. 88 m), and the length is 153 in. (3.89 m). The predicted four-engine aircraft noise levels during takeoff and approach are 105.6 and 104. 1 PNdB, respectively. f i f- PRECEDING PAGE,,-BLANK NOT FILMED. TABLE OF CONTENTS Section Title Page ISummary . 1-1 IIIntroduction . 2-1 III Technical Approach . 3-1 3a Cycle Performance Characteristics . 3a-1 Parametric Analysis . 3a-1 Task II Cycle . 3a-6 3b Summary of Engine Configurations Studied . 3b-1 3c Noise Evaluation . 3c-1 Analysis Method . 3c-1 Fan and Compressor Noise . 3c-1 Mach Noise . 3c-2 Jet Noise . 3c-2 Turbine Noise . 3c-3 Noise Summation . 3c-3 Correlation with Measured Noise . 3c-5 Design Change Effects . 3c-5 Hub-to-Tip Ratio . 3c-5 Tip Mach Number Effects . 3c-6 Single-Stage Versus Multistage Fans . 3c-8 Two-Spool Versus Three-Spool Designs . 3c-8 Initial Study Engines . 3c-8 Optimization Studies for PD218-Q Engine . 3c-12 IPCompressor . 3c-12 Fan . 3c-12 Engine . 3c-13 Perceived Noise at Flight Path Locations . 3c-14 Effects of Duct Treatment . 3c-20 Inlet Treatment . 3c-20 Fan Discharge Duct Treatment . 3c-20 Effect of Duct Treatment on Study Engines . 3c-21 Noise Exposure Contours . 3c-22 Effective Perceived Noise Levels . 3c-29 3d PD218-Q Engine Description . 3d-1 3dl Weight Analysis . 3dl-1 3d2Fan . 3d2-1 iii Section Title Page tee...._ Aerodynamic Design. .. 3d2-1 General . .. 3d2-1 = Parametric Studies . 3d2-4 Vector Diagrams . 3d2-7 ^a= Mechanical Design . 3d2-7 Aeroelastic Study . 3d2-24 30 Compressor . 3d3-1 = Aerodynamic Design . 30-1 General . 30-1 IPCompressor . 30-1 HPCompressor . 3d3-8 Mechanical Design . 30-13 IP Compressor . 30-13 HP Compressor . 3d3-17 Materials . 3d3-21 3d4 Diffuser and Combustor . 3d4-1 Aerodynamic Design . 3d4-1 General . 3d4-1 Diffuser . 3d4-3 Combustor . 3d4-5 Diffuser and Combustor . 3d4-5 i = Mechanical Design . 3d4-5 Diffuser . 3d4-5 Combustor . 3d4-6 Materials . 3d4-7 - 3d5Turbine . 3d5-1 Aerodynamic Design . 3d5-1 HPTurbine . 3d5-1 - IP Turbine 3d5-2 - LPTurbine . 3d5-7 Mechanical Design . 3d5-13 HPTurbine . 3d5-13 IPTurbine . 3d5-18 LP Turbine . .. 3d5-19 - Materials . 3d5-20 3d6 Accessory Drive . 3d6-1 3d7 Bearings, Seals, and Shafting . 3d7-1 Bearings . 3d7-1 Seals . 3d7-3 Shafting . 3d7-8 Materials . 3d7-8 iv 3 Section Title Page 3d8 Engine Structural Requirements . 3d8-1 3d9 Lubrication System . 3d9-1 Pressure System . 3d9-2 Scavenge System . 3d9-5 3d10 Fuel and Control System . 3d10-1 Control Mode . 3d10-1 Control System Description . 3d10-2 3dll Engine Installation . 3dll-1 IV Symbols and Units . .. 0 4-1 VReferences. 0 5-1 i v LIST OF ILLUSTRATIONS g Figure Title Page 3a-1 Effects of fan pressure on throttle performance- 5;1 bypass ratio . 3a-2 3a-2 Effects of fan performance on sfc at mid-cruise thrust . 3a-2 3a-3 Effects of fan performance on weight-traded tsfc at mid-cruise . 3a-3 3a-4 Effects of TIT on total net thrust and tsfc. 3a-3 F 3a-5 Effects of TIT on tsfc at 7519 thrust, mid-point cruise . 3a-4 3a-6 Effects of TIT on weight-traded tsfc at mid-point cruise. 3a-4 3a-7 Effects of overall pressure on total net thrust and tsfc. 3a-5 3a-8 Effects of overall pressure ratio on tsfc . 3a-5 3a-9 Engine operating envelope . 3a-8 3a-10 Cycle station number nomenclature . 3a-9 3b-1 PD218-5A1 engine cross section . 3b-5 3b-2 PD218-5B1 engine cross section . 3b-7 3b-3 PD218-3131 engine cross section . 3b -9 3b-4 PD218-Q engine cross section . 3b-13 3c-1 Effect of jet noise on jet relative velocity . 3c -3 3c-2 Octave band jet noise versus S n—ground . 3c -4 3c -3 Octave band jet noise versus Sn--flight . 3c-4 3c -4 Correlation of predicted and measured noise . 3c-6 3c-5 Fan H/T ratio versus perceived noise level . 3c -7 3c -6 Flap, gear, aircraft speed, and power setting for DC-8/707 transport . 3c-16 3c-7 Quiet engine study flight path comparison . 3c-16 3c-8 Standard noise monitor positions . 3c-17 3c-9 Treated duct locations . 3c -21 3c-10 Aircraft flight path and community noise exposure . 3c -22 3c-11 PNdB contour for JT31) takeoff . 3c-23 3c-12 PNdB contour for JT3D approach . 3c-23 3c-13 PNdB contour for PD218-5A1 takeoff . 3c -24 I 3 3c-14 PNdB contour for PD218-5A1 approach. 3c-24 3c-15 PNdB contour for PD218-5131 takeoff . 3c -25 3c-16 PNdB contour for PD218-5131 approach . 3c -25 3c-17 PNdB contour for PD218-3131 takeoff . 3c -26 3c-18 PNdB contour for PD218-3B1 approach . 3c -26 3c-19 PNdB contour for PD218 -Q takeoff . 3c-27 3c-20 PNdB contour for PD218 -Q approach . 3c -27 3c-21 Flyover 1/3 octave band spectrum for PD218-Q engine . 3c-30 3c-22 PD218-Q takeoff noise duration time for four-engine aircraft 3 miles (4.83 km) from brake release . .. 3c-40 i vi Figure Title Page 3c-23 PD218-Q approach noise duration time for four- engine aircraft 1 mile (1.61 km) from end of runway . 3c-31 3d-1 PD218-Q engine cross section . ..
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