Radial turbines are a class of turbomachinery that extracts work from a high-energy workingfluid. Contrary to an axial turbine seen on commercial aircraft, where the working fluid (air)travels through the turbine without having a bulk change in direction, radial turbines createhighly three-dimensional flow, with the fluid leaving the turbine perpendicular to its inflowdirection. To aid radial turbomachinery design, automated optimisation algorithms based oncomputational fluid dynamics (CFD) analysis have been developed - many of these algorithmsrely on prior knowledge of good turbine design, reducing automation and increasing relianceon operator skill. To alleviate this problem, the design space allocated to the optimisationalgorithm must be as large as possible. To work towards this goal, this thesis focusses onthe creation of radial turbine CFD mesh geometry using Bezier curves, the advantage of suchcurves being the ability to modify a series of control points defining the curve to manipulateits shape, while maintaining smooth interface with the remainder of the mesh. Defining theturbine geometry in such a way allows arbitrary changes to be made to the shape of the fluidpassage. To validate the implementation of this modification to the geometry definition, CFDsimulations were run with various passage shapes, including a scenario exploring the effectsof splitter blades on the flow field. The methodology was found to be sound, successfullyallowing manipulation of the turbine geometry in the form of additional structures added to themesh. It was therefore concluded that the methodology is promising as a proof-of-concept, andwill provide a baseline for future forays into the implementation of an optimisation algorithm.While not included in the scope of this thesis, the future application of this work is in theimplementation of an automated optimisation algorithm. The Bezier curve control points will ´be automatically modified by the optimisation algorithm, allowing the shape of the turbine tobe morphed for aerodynamic advantage, generating highly efficient turbine designs.