Simulation of an aerodynamic profile with sections of ad hoc concavity

The article describes the study carried out by the authors of the use of parametric geometric models to reduce the complexity of the design of parts that follow the theoretical contour of the bearing surfaces of the aircraft. Also, an algorithm that allows eliminating the existing ad hoc concavity profile is considered.

Designing Forging and Die Tooling for the Manufacture of Turbine Engine Compressor Blades in Siemens NX

For designing forging and die tooling for bulk forging a necessity in using the data of the geometry of the part produced arises. Obviously, the use as a data source for designing drawings of commonly applied in “manual alternate design” (without a computer) especially such complex parts as compressor blades is not perspective because of the complexity of developing theoretical contour specified by a point cloud. In this case the use of special tooling of direct modeling that provides changing the original model of the part developed by the designers is a perspective one. It should be taken into account during the process of forging and die tooling designing that it is necessary to register the special features of the technology, upon that, the technologist should be highly proficient in using the software. The work given describes the designing technique of gas turbine compressor blade with the account of using the potential of NX Siemens program.

A New Method for Evaluating the Profile of Large Paraboloidal Antennas

In order to solve the problem of installation and measuring errors in the profile evaluation of large parabolic antennas, this paper proposes a new method for evaluating the profile of large paraboloidal antennas based on genetic algorithm and least square method. This method can effectively realize the adaptive adjustment of the measured points and the theoretical contour in the process of evaluating profile, which can eliminate the position error between the measured points and the theoretical contour that influences on the results of the profile evaluation. The availability of this method has been proved by simulation.

Machining Theory of Forming Complex Inner Helicoid and Numerical Algorithm to Design Contour of the Disc-Mill Cuter

The inner helicoid of the PDM’s stator is a kind of typical inner surface that is complex and tenuous. This paper studies the theory to form the inner helicoid in the screw stator which has a large lead and whose cross-section is composed by convex and concave curves using disc milling method. According to the varieties of the curve types of workpiece’s cross-section, a numerical method was proposed to calculate the theoretical contour shape of the disc milling cutter using coordinates of the fewer points on the workpiece’s cross-section. The manufacturing test confirmed the correctness of the design algorithm of the cutter’s profile and feasibility of this milling forming method.