Evaluation of thrust from a multi-nozzle output device with single input

Abstract

A multi-nozzle output device with a single input, is designed and optimized using Computational Fluid Dynamics techniques and thrust is evaluated. In this regard a platform, having required number of nozzles is designed and using a distribution chamber, working fluid is supplied to each nozzle efficiently, maximizing the net thrust developed. Using a 3D modeling software, the geometry is created and imported to a commercial CFD code. A non-structured grid having tetrahedral elements is generated to investigate the fluid flow. An additional fluid domain is used to analyze the fluid flow after leaving the nozzles. Pressure difference maintained to generate the fluid flow is determined by optimizing the nozzles iteratively. Incompressible air is used as working fluid with k-epsilon turbulence model. Steady state simulations with different mesh sizes are performed to achieve a grid independent solution. By reducing the weight of device and controlling the distribution of fluid in different nozzles, optimization is performed to maximize the thrust. Taking into consideration, the Mach number, noise of fluid ejecting from nozzles is reduced. Device is designed to lift the additional weight. A device capable of carrying such amount of weight with fluid ejecting at low Mach number is one of its own kind and find its application in silent rapid movements without any considerable disturbance in its wake.