Khaled Almohammadi

Taibah University · Mechanical Engineering

The study of energy savings in ventilation systems within buildings is crucial. Impinging jet ventilation (IJV) systems have garnered significant interest from researchers. The identification of the appropriate location for the IJV reveals a gap in the existing literature. This research was conducted to address the existing gap by examining the imp...

Vertical axis wind turbines (VAWTs) are expected to have good market potential in the near future. However, it suffers from relatively lower performance in contrast with the market-leading horizontal axis wind turbine (HAWT). To overcome the disadvantages of VAWTs and improve their performance, this study aims to experimentally investigate the effe...

In this work, an Hybrid Renewable Energy System (HRES) based on microgrid power is proposed and optimized to meet the electric demand of a sustainable multi-family buildings with possible generation of clean hydrogen. Hourly building simulation is carried out based on meteorological data to predict the year-round electrical consumption of the desig...

This paper investigates modelling strategies on the prediction of lift and drag coefficients of a NACA0012 airfoil at Reynolds number of 360,000. Two computational methods are employed; namely Navier-Stokes equation and panel method, by using different tools for computing lift and drag coefficients. The obtained results are compared against experim...

Traditional cooling and desalination cycles consume great amount of energy and pollute the environment. Reverse osmosis (RO) process is the most used desalination system due to high operation efficiency, but it produces large concentrated brine leading to damage the ecosystem. In this study, a new proposed hybrid absorption desalination cooling (AB...

Sorption cooling technology is considered to be a good alternative to traditional vapor compression cycles regarding energy savings and environmental issues. This technology has to be enhanced to overcome the problem of low efficacy. In this work, a novel solar-powered combined absorption–adsorption cooling system (ABADS) is proposed and investigat...

A backward facing step (BFS) flow has been investigated extensively by the research community experimentally and computationally due to its significant flow features because of the presence of the separation-reattachment mechanism. The strength of this mechanism varies based on the Reynolds number (RN). For turbulent flow at low RN, the separation-...

Significant research is being conducted in the simulation of fluid flows due to the increase in employing the physics of the fluid flow to either commercial, in-house or open source codes. The analysis of the fluid flow is mainly based on the Lagrangian or the Eulerian approach. Many of the simulation codes employ the Eulerian approach due to its s...

Energy is the most valuable parameter in human life. Straight blade vertical axis wind turbines (SB-VAWT) are employed to harness wind energy. In this paper, an experimental study of the wind turbine was performed in a wind tunnel with a test section area of 2600 cm² with a speed range of 1-10 m/s. The turbine has two sets of airfoil made of Alumin...

This paper investigates the development of the dynamic stall of a full straight blade vertical axis wind turbine (SB-VAWT) using computational fluid dynamic modeling for solving the 2D Navier–Stokes equations. The 2D unsteady Navier–Stokes equations are solved with the concept of Reynolds averaging. A mesh independency test is analyzed using the Ge...

This paper numerically investigates the effect of the trailing edge profile on the performance of the straight-blade vertical axis wind turbine (SB-VAWT). In a 2-D cross-section of the SB-VAWT model, four trailing edge profiles are investigated, namely sharp, rounded, S-blunt, and R-blunt. The numerical investigation is based on the unsteady Reynol...

The flow around straight blade vertical axis wind turbines is typically complex at low tip speed ratios (TSR < 2). In this paper, the turbulence models which are based on the assumption of fully developed turbulent flow, such as S-A, RNG κ-ε and SST κ-ω have been investigated in comparison to the SST transitional model (both with and without curvat...

This paper numerically investigates four methods, namely mesh refinement, General Richardson Extrapolation (GRE), Grid Convergence Index (GCI), and the fitting method, in order to obtain a mesh independent solution for a straight blade vertical axis wind turbine (SB-VAWT) power curve using computational fluid dynamics (CFD). The solution is produce...

This paper investigates the flow field features and the predicted power coefficient of a straight blade vertical axis wind turbine (SB-VAWT) using computational fluid dynamics modeling using 2D simulations. The Unsteady Navier-Stokes equations are solved with the concept of Reynolds averaging using the commercial software FLUENT and the sliding mes...

The flow around straight blade vertical axis wind turbines is typically complex at low tip speed ratios (TSR < 2). In this paper, the turbulence models which are based on the assumption of fully developed turbulent flow, such as S-A, RNG κ-ε and SST κ-ω have been investigated in comparison to the SST transitional model (both with and without curvat...

Many attempts have been carried out in the past few years to build a general understanding of the straight blade vertical axis wind turbine aerodynamics. For this purpose many models have been developed. These models may be classified into four main categories: momentum, vortex, cascade and computational fluid dynamic based modelling. The computati...

In the last few decades, the consumption of energy has been significantly increased. As energy sources in the world are being depleted, wind energy becomes one of the most promising and reliable sources of energy. In this paper a 2-D straight blade vertical axis wind turbine is analyzed using Fluent in order to compare its performance at different...

The fixed-pitch straight-bladed vertical axis wind turbine (SB-VAWT) is one of the simplest types of wind turbine. The overall cost of the SB-VAWT will mainly depend on judicious choice of multiple design parameters. An attempt has been made in this paper to analyze the influence of three design parameters related to smaller-capacity fixed-pitch SB...