PERFORMANCE ANALYSIS OF PSO-PD CONTROLLER IN CONTROLING THE RIGID GANTRY CRANE SYSTEM

Karya tulis ini membahas tentang algoritma particle swarm optimization (PSO) untuk mengoptimalkan penguat pengendali PD yang dinamakan pengendali PSO-PD. Efektivitas algoritma pengendali yang diusulkan diuji dengan menggunakan fungsi step dan dibandingkan dengan pengendali PD berbasis Zigler-Nichols (ZN-PD). Hasil simulasi yang didapatkan menunjukkan bahwa pengendali PSO-PD menghasilkan waktu naik dan waktu puncak yang lebih lambat dibandingkan dengan pengendali ZN-PD, tetapi memiliki waktu tunak yang lebih cepat dan nilai overshoot yang kecil di bawah trayektori yang didefinisikan.Kata kunci: Sistem gantry crane, PSO, Gain PD, Sudut ayunan AbstractThis paper presents the particle swarm optimization (PSO) algorithm to optimize the gains of the PD controller to form what so-called the particle swarm optimization (PSO-PD) controller. The effectiveness of the proposed control algorithm is tested under constant step function and compared with Ziegler-Nichols (ZN-PD) controller. Simulation results show that proposed controller has slower rise time and peak time than ZN-PD controller as well as small overshoot under the predefined trajectories

Cascade Optimization of an Axial-Flow Hydraulic Turbine Type Propeller by a Genetic Algorithm

This study proposes the use of the genetic algorithm (GA) method in hydraulic turbine optimization for renewable energy applications. The algorithm is used to optimize the performance of a two-dimensional hydrofoil cascade for an axial-flow hydraulic turbine. The potential flow around the cascade is analyzed using the surface vorticity panel method, with a modified coupling coefficient to deal with the turbine cascade. Each section of the guide vane and runner blade hydrofoil cascade is optimized to satisfy the shock-free criterion, which is the fluid dynamic ideal to achieve minimum profile losses. Comparison is also made between the direct and random switching methods for the GA crossover operator. The optimization results show that the random switching method outperforms the performance of the direct switching method in terms of the resulting solutions, as well as in terms of the computational time required to reach convergence. As an alternative to experimental trials, the performance of both turbine designs are predicted and analyzed using the three-dimensional computational fluid dynamics (CFD) approach under several operating conditions. The simulation results show that the optimized design, which is obtained by applying the shock-free criterion using the GA, successfully improves the performance of the initial turbine design

Analysis and analytical modeling of wake aerodynamics behind horizontal-axis wind turbines

豊橋技術科学大

SIMULASI NUMERIK POLA ALIRAN PLUG AIR-UDARA PADA PIPA HORISONTAL MENGGUNAKAN EULERIAN MODEL

Phenomenon of an air-water plug flow regime in horizontal pipes is simulated with Computational Fluid Dynamics (CFD). Simulations performed with 3-dimensional computational domain, transient, using commercial software FLUENT 6.3.26. Multiphase model that used is Eulerian model. Eulerian model solved continuity and momentum equations for each phase. On plug flow regime simulations, before liquid slug has formed, it begins with wave formation at the air-water interface. To be able to appearing Kelvin-Helmholtz instability which is the begining of wave formation, it is necessary to make perturbation at the air-water interface. In this research, perturbation at the velocity inlet boundary conditions is done by two methods, with sinusoidal velocity at the velocity inlet boundary conditions, and a sinusoidal arrangement of water level at the velcoity inlet boundary conditions. The results from both methods were compared to determine the effect of the superficial velocity of water and air against gas bubble length. Based on simulation results and experimental data, the greater the difference between the water and the superficial velocity of the air, then the length of the gas bubble is getting shorter. That is because when the superficial velocity difference between the two phases increase, then the slip velocity at the interface between the two phases is also getting bigger. The magnitude of the slip velocity effect on the magnitude of the drag force which is the force of interaction between the two phases. The greater the drag force, the force that drives the water - air interface to be lifted to the top is getting bigger, so that the liquid slug is formed faster. This causes the length of the gas bubble is getting shorter. The results of numerical simulations showed good agreement when validated with experimental data