This doctoral thesis represents a set of new ideas, methods and research results related to improving the efficiency of functioning of ship power plants (SPP) of combined propulsion complexes (CPC). The main motivation for these studies is the existing current practice requests for the operation of the SPP CPC, such as: ensuring minimization of irreversible losses in the transmission of capacities from the SPP to the engines of the CPC; the need to improve the monitoring of the transfer of capacities in the SPP CPC with dynamic principles of retaining the vessel; increasing the operational reliability and strength of the SPP CPC; creation of new and improvement of existing decision support systems (DSS) during operation, research and design of the SPP CPC.
Based on the analysis of the existing state of the development of the SPP CPC, the following unresolved problems were found on the lines of propellers, in power systems of motors for thrusters and power distribution systems.
As a result of solving the main and auxiliary tasks, the following scientific positions were obtained: improvement of the method of computational hydrodynamics is provided by using the distribution of the sought-for intensities of the degradation effects from the interaction of the propeller flows among themselves and the CPC body due to the use of piezoelectric sensors on the shaft lines of azimuth thruster. Compensation of degradation effects is achieved by calculation of power flows from azimuth thrusters in the form of a power drive disc, which allows identifying turbulent regions with relative vortex viscosity coefficients μt/μw. Calculation of the components of the x-velocities at the intersection of the propeller flow along the axis of rotation with dimensions in units of the diameter of the DP propeller makes it possible to realize the method of surface-oriented averaging of the Reynolds-Navier-Stokes equation for mass transfer at the interface; limitations on power and torque on the shaft lines of the SPP CPC thruster of dynamically positioning vessels are provided by redistribution of the thrusts between the thrusters or the reduction of the maximum load as part of the algorithm for distributing the thrust of the DP system due to the application of the strategy of full range speed governors in relation to operating conditions; for the first time, a three-level multi-criteria strategy for managing the distribution of energy in the hybrid SPP CPC was developed by integrating the classical strategy of power distribution management with a strategy of control over the state of the MSDG and the degree of charge of the energy storage system alternative generating element. The developed strategy differs from existing by higher speed detection of risk of de-energization of ship electric power system, greater reliability and accuracy in determining the need for load reduction and the thruster speed of rotation fully integrated with variable speed governors and power supply system; for the first time, the DSS was created to study the ways of automating and computerizing the design and operation processes of the SPP CPC, which being based on theoretical, design and experimental methods, has enabled the introduction of a comprehensive substantiation, verification and self-testing of the developed components of the methodological and mathematical apparatus; for the first time, a physical model of a multifunctional CPC with a variable structure was created, which, in synergy with the solution of the problem of DSS development, allows iterative analysis of the structures of the SPP CPC with minimal initial data; the law of pulsations of thrusts on the lines of propeller shafts is established, which occur under conditions of interaction of several thrusters with each other and with the CPC body.
Also, for the first time, the dependencies of the thrusts and torques of the azimuth thruster were determined as a result of the interaction of the propeller flow with the hull and the stock due to the occurrence of degradation effects; for the first time, a simplified semi-empirical method for iterative progressively regressive parameterization of the SPP CPC was developed in off-design operation modes, which generalizes the previously relationship, which have been derived for thrusts and torques of co-axial CPP s in a homogeneous flow with ratios known from the theory of turbomachines for the case of interaction between the stationary propeller and the azimuth thruster.
