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Numerical simulation of subsonic and transonic propeller flow. ph.d. thesis
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Snyder, Aaron |
| Copyright Year | 1988 |
| Description | The numerical simulation of 3-D transonic flow about a system of propeller blades is investigated. In particular, it is shown that the use of helical coordinates significantly simplifies the form of the governing equation when the propeller system is assumed to be surrounded by an irrotational flow field of an inviscid fluid. The unsteady small disturbance equation, valid for lightly loaded blades and expressed in helical coordinates, is derived from the general blade-fixed potential equation, given for an arbitrary coordinate system. The use of a coordinate system which inherently adapts to the mean flow results in a disturbance equation requiring relatively few terms to accurately model the physics of the flow. Furthermore, the helical coordinate system presented here is novel in that it is periodic in the circumferential direction while, simultaneously, maintaining orthogonal properties at the mean blade locations. The periodic characteristic allows a complete cascade of blades to be treated, and the orthogonality property affords straightforward treatment of blade boundary conditions. An ADI numerical scheme is used to compute the solution of the steady flow as an asymptotic limit of an unsteady flow. As an example of the method, solutions are presented for subsonic and transonic flow about a 5 percent thick bicircular arc blade of an 8-bladed cascade. Both high and low advance ratio cases are computed and include a lifting as well as nonlifting cases. The nonlifting solutions obtained are compared to solutions from a Euler code. |
| File Size | 5387067 |
| Page Count | 191 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19880010878 |
| Archival Resource Key | ark:/13960/t4rj9bm0v |
| Language | English |
| Publisher Date | 1988-04-01 |
| Access Restriction | Open |
| Subject Keyword | Aerodynamics Propeller Slipstreams Transonic Flow Steady Flow Unsteady Flow Orthogonality Potential Flow Propeller Blades Numerical Analysis Simulation Three Dimensional Flow Subsonic Flow Euler Equations of Motion Helical Flow Inviscid Flow Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Thesis |
