in according to the simplicity of the lattice boltzmann method’s(lbm) algorithm and its benefits, it has been used as a successful method in computational fluid dynamics in the last decades. in this paper, lbm was used to simulate the flow over a cylinder. to analyze the application of lbm in simulation curved surface, different methods to compute drag coefficient were used. these methods are: ...

Designing curved folds of a developable surface remains an open problem. No analytical method for the design of curved folds has been reported. Although optimization methods exist, it is difficult to interactively design valid curved folds of a single developable surface using such methods. In the present paper, we propose an interactive system for designing a surface with planar curved folds b...

In gas turbines, the hot exiting combustor can have temperatures as high 2000 °C, and some of this enter into space between stator rotor disks (wheelspace). Since entering could damage disks, its ingestion must be minimized. This is carried out by rim seals introducing a cooler flow from compressor (sealing flow) wheelspace. Ingress egress are driven vanes, rotation, blades. study focuses on in...

A clearance gap (CG) between guide vanes (GVs) and facing plates exists at both ends of a Francis turbine allows the opening angle to be adjusted for varying operating conditions. Leakage flow is induced through this due pressure difference two sides vanes. While some research works have used qualitative approaches visualize predict strength leakage vortex (LV), paper presents method quantifyin...

Abstract Rim seals are critical in terms of limiting the temperature highly stressed engine components but function with a penalty to power output and contribute entropy gain stemming from mixing losses turbine. Ingress through rim is influenced by presence rotor blades stator vanes, mainstream flow coefficient annulus that determines corresponding swirl. This paper presents an experimental stu...

In this paper, implementation of an extended form of a no-slip wall boundary condition is presented for the three-dimensional (3-D) lattice Boltzmann method (LBM) for solving the incompressible fluid flows with complex geometries. The boundary condition is based on the off-lattice scheme with a polynomial interpolation which is used to reconstruct the curved or irregular wall boundary on the ne...

Hydraulic turbines are increasingly used to regulate the electrical grid. They thus have operate more often at off-design conditions where instabilities may develop leading large pressure pulsations decreasing life of machines. In present study, an adjustable guide vane system in draft tube a single regulated hydraulic turbine is developed. The aim mitigate when operates part load operational r...

Variable inlet guide vanes (VIGVs) are widely used for flow throttling and also extending the operating range of centrifugal compressors. Although there several studies on effects adding IGVs performance curve compressors, none them have focused number vanes. In current study, high-fidelity three-dimensional numerical simulations carried out to analyze VIGVs with different aerodynamic a single-...