A Comparison of Lifting-Line and CFD Methods with Flight Test Data from a Research Puma Helicopter


Book Description

Four lifting-line methods were compared with flight test data from a research Puma helicopter and the accuracy assessed over a wide range of flight speeds. Hybrid CFD methods were also examined for two high-speed conditions. A parallel analytical effort was performed with the lifting-line methods to assess the effects of modeling assumptions and this provided insight into the adequacy of these methods for load predictions.




A Comparison of Lifting-Line and Cfd Methods with Flight Test Data from a Research Puma Helicopter


Book Description

Four lifting-line methods were compared with flight test data from a research Puma helicopter and the accuracy assessed over a wide range of flight speeds. Hybrid Computational Fluid Dynamics (CFD) methods were also examined for two high-speed conditions. A parallel analytical effort was performed with the lifting-line methods to assess the effects of modeling assumptions and this provided insight into the adequacy of these methods for load predictions. Bousman, William G. and Young, Colin and Toulmay, Francois and Gilbert, Neil E. and Strawn, Roger C. and Miller, Judith V. and Maier, Thomas H. and Costes, Michel and Beaumier, Philippe Ames Research Center NASA-TM-110421, NAS 1.15: 110421, A-962753, USAATCOM TR-96-A-008 RTOP 505-59-87...










Putting the Aero Back Into Aeroelasticity


Book Description

The lack of progress in understanding the physics of rotorcraft loads and vibration over the last 30 years is addressed in this paper. As befits this extraordinarily difficult problem, the reasons for the lack of progress are complicated and difficult to ascertain. It is proposed here that the difficulty lies within at least three areas: 1) a loss of perspective as to what are the key factors in rotor loads and vibration, 2) the overlooking of serious unsolved problems in the field, and 3) cultural barriers that impede progress. Some criteria are suggested for future research to provide a more concentrated focus on the problem.
















Correlation of Puma Airloads


Book Description

A cooperative program was undertaken by research organizations in England, France, Australia and the U.S. to study the capabilities of computational fluid dynamics codes (CFD) to predict the aerodynamic loading on helicopter rotor blades. The program goal is to compare predictions with experimental data for flight tests of a research Puma helicopter with rectangular and swept tip blades. Two topics are studied. First, computed results from three CFD codes are compared for flight test cases where all three codes use the same partial inflow-angle boundary conditions. Second, one of the CFD codes (FPR) is iteratively coupled with the CAMRAD/JA helicopter performance code. These results are compared with experimental data and with an uncoupled CAMRAD/JA solution. The influence of flow field unsteadiness is found to play an important role in the blade aerodynamics. Alternate boundary conditions are suggested in order to properly model this unsteadiness in the CFD codes. Strawn, Roger C. and Desopper, Andre and Miller, Judith and Jones, Alan Ames Research Center NASA-TM-102226, A-89223, NAS 1.15:102226, USAAVSCOM-TM-89-A-001 RTOP 992-21-01...