Using the Wave Equation for Actuator Surface Analysis

Natalya Rogozhan
Work towards MSc degree under the supervision of Prof. Em Aviv Rosen (AE/Technion)
Department of Aerospace Engineering
Technion – Israel Institute of Technology

The design of rotary-wing systems requires knowledge of the forces acting on the blades, as well as the airflow over them. One of the commonly used methods for calculating the velocities induced by rotary-wings is based on the actuator disc (actuator surface) concept. In many cases, the concept is implemented using the momentum theory. According to this model, the rotary wing is replaced by an infinitely thin disc, which causes a discontinuity in few of the flow parameters while passing through the disc. The model is simple, efficient and in most cases shows good agreement with test results. Yet, the momentum theory also has disadvantages, such as incapability of predicting the entire flow-field. The current research includes a development of a new actuator surface model, based on a solution of the wave equation. The basic model includes a distribution of dipoles over a surface, representing the forces applied on the flow by the blades. More complex flow cases can be described by extending the basic model to include a distribution of both dipoles and quadrupoles over the surface. While being relatively simple, efficient and easy to apply, the model provides data that cannot be obtained using the momentum theory. Using the present model, the solution of the entire velocity field, including the axial and in-plane components of the flow, may be obtained. Comparison between the results of a model based on the momentum theory and the present model exhibits a good agreement.

The talk will be given in Hebrew

Wed, 29-06-2022, 13:30-14:30 (Gathering at 13:15)

Classroom 165, ground floor, Library, Aerospace Eng. &

Light refreshments will be served before the lecture at the classroom

Using the Wave Equation for Actuator Surface Analysis