, M.Sc. Thesis Sharif University of Technology Ounaghi, Mohammad Safa (Author) ; Abbaspour, Madjid (Supervisor)

Abstract

In order to design a ship with waterjet system, estimation of its hydrodynamic performance is crucial. Presence and operation of waterjet propulsion system changes the flow field and pressure distribution in bottom and stem of ship hull, so affect hydrodynamic performance of craft. In the present thesis, CFD analysis is applied to free surface flow around a waterjet propelled ship using ANSYS CFX software. Also a waterjet propulsion system is built and settled in a ship model and resistance and self propulsion tests are performed. In order to performing a systematic process in project, in the first step, pump design is performed with extracting optimum efficiency relations and cavitation...

Solids Mixing Behavior in two Dimensional Fluidized bed with Inlet Jet Effect

, M.Sc. Thesis Sharif University of Technology Fadaei, Hooman (Author) ; Molaei Dehkordi, Asghar (Supervisor)

Abstract

In this study, the mixing and segregation of different mixtures of solid particles with various density or size in gas-solid fluidized beds have been investigated. In this regard, the integrated model of computational fluid dynamics and discrete particle method (CFD-DPM) were used. The soft sphere contact scheme and the linear dashpot-spring model were applied for to evaluate the contact forces. After validating the simulation results with experimental data from the literature, effects of an inlet gas jet were investigated by using some quantitative and qualitative mixing indexes. Effects of gas velocity, percentage of heavy particles, density and particle size ratio, initial arrangement of...

Performance Optimization of an Axisymmetric Supersonic Inlet

, M.Sc. Thesis Sharif University of Technology Mahdavi, Mohammad Mahdi (Author) ; Farahani, Mohammad (Supervisor)

Abstract

The main aim of this study is to propose a new structure of compression surfaces of a supersonic inlet in order to improve target performance parameter i.e. total pressure recovery ratio. This idea resulted in developing a new type of supersonic inlet, utilizing four ramps and a cone as compression surfaces simultaneously.A prototype of this type of inlet has been designed for Mach 3 and its performance has been studied via numerical simulation in design point and off design conditions. Eventually the new inlet compared to experimental performance survey data from two cases of two-cone inlets and also analytical calculations of ideal performance of some types of supersonic inlets. Results of...

Experimental Investigation of the Performance of a Body Integrated Diverterless Supersonic Inlet

, Ph.D. Dissertation Sharif University of Technology Askari, Rasoul (Author) ; Soltani, Mohammad Reza (Supervisor)

Abstract

Supersonic inlets, as one of the most important components of fighter aircraft, are designed to provide the required airflow with an acceptable level of energy and quality and with a minimum drag. From the inlet design point of view, there exist various configurations that are based on different criterion such as supersonic flow compression region, flow dimensions, and installation position, to name a few. The flight Mach number, M∞, could further complicate the design and structure of these types of inlets. One of the requirements for minimum drag is that at supersonic speed the shock wave that forms in front of the inlet must impinge on the cowl lip, called shock on lip condition (SOL). ...