1、SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirelyvoluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefro
2、m, is the sole responsibility of the user.”SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions.Copyright 1997 Society of Automotive Engineers, Inc.All rights reserved. Printed in U.S.
3、A.QUESTIONS REGARDING THIS DOCUMENT: (412) 772-8510 FAX: (412) 776-0243TO PLACE A DOCUMENT ORDER: (412) 776-4970 FAX: (412) 776-0790400 Commonwealth Drive, Warrendale, PA 15096-0001AEROSPACERECOMMENDEDPRACTICESubmitted for recognition as an American National StandardARP704REV.AIssued 1962-06Reaffirm
4、ed 1991-05Revised 1997-05Superseding ARP704Helicopter Engine-Rotor System CompatibilityFOREWORDChanges in this revision are format/editorial only.1. SCOPE:This SAE Aerospace Recommended Practice (ARP) recommends a methodology to be used for the design, analysis and test evaluation of modern helicopt
5、er gas turbine propulsion system stability and transient response characteristics. This methodology utilizes the computational power of modern digital computers to more thoroughly analyze, simulate and bench-test the helicopter engine/rotor system speed control loop over the flight envelope. This up
6、-front work results in significantly less effort expended during flight test and delivers a more effective system into service.The methodology presented herein is recommended for modern digital electronic propulsion control systems and also for traditional analog and hydromechanical systems.2. REFER
7、ENCES:There are no referenced publications specified herein.3. Helicopter and engine designers recognize that turbine engine governor-rotor system compatibility problems may exist. This problem is felt to be of mutual concern to both parties, and to be due to the introduction of automatic rotor spee
8、d governing.4. The major compatibility problem is one of resonance, which can lead to instability at or near resonant frequency.a. This resonance is not apparent in reciprocating or turboprop open loop control systems.b. This resonance is apparent in shaft turbine closed loop control systems.SAE ARP
9、704 Revision A- 2 -5. The critical dynamic parameters appear to be:a. helicopter damping characteristicsb. helicopter component stiffness (rotor, shaft, gears, etc.)c. helicopter rotor inertiad. engine power train inertiae. engine dynamic characteristics (time lags, transport phenomena, damping, eng
10、ine operating limits, etc.)f. engine governor dynamic characteristics (response time, damping, static gain)g. helicopter lag hinge spring constanth. lag hinge damper characteristicsi. helicopter rotor response requirements6. To more effectively achieve satisfactory helicopter-engine system operation
11、al characteristics, the following procedures are recommended:a. Phase I - Engine Design and Development1. Engine designer to conduct preliminary studies in advance of firm applications to provide greatest universality and adaptability in recognition of potential compatibility problems.2. Engine desi
12、gner to design and develop a basic governor in light of Item 6.a.1 above.3. Engine designer to determine parameter range and transfer functions of the engine and its controls.4. Engine designer may supplement engine model specifications with information determined in Item 6.a.3 above, when required.
13、b. Phase II - Engine Application - Preliminary Helicopter Design1. Helicopter designer to supply estimated rotor system dynamic characteristics during design stage. (A typical form is spring-inertia diagram. See Figure 1.)2. Both helicopter and engine designers to carry out studies and coordinate re
14、sults.3. Both helicopter and engine designers to determine the possible methods for correcting problems as indicated.SAE ARP704 Revision A- 3 -FIGURE 1SAE ARP704 Revision A- 4 -6. (Continued):c. Phase III - Helicopter Development1. Helicopter designer to decide which of the solutions in Item 6.b.3 i
15、s to be implemented and negotiate accordingly.2. Helicopter designer to coordinate dynamic revisions required.3. Helicopter designer to establish compatibility test requirements in consultation with the engine designer.4. Helicopter designer to run official demonstration.7. In order to accomplish ef
16、fectively the objectives of the recommended practice, the eventual recognition of all the foregoing, and consequent specification action will be required by the cognizant agency. This shall include methods of data presentation. In addition, it is recommended that the compatibility requirements of tu
17、rboprop and shaft turbine engines be properly differentiated by the cognizant agencies in their specifications.NOTE: Although not officially part of this ARP it is recommended that a study be implemented to determine the feasibility of defining parametric limits for use as possible standards in establishing a compatibility specification.PREPARED BY SAE COMMITTEE S-12, HELICOPTER POWERPLANT
