Ojo Kurdi

Modeling of Hydrogel Coated Fiber Bragg Grating pH Sensor

This paper present the modeling and simulation of the hydrogel coated FBG for pH sensor application. The hydrogel swelling was modeled by using Poisson-Nernst-Planck equation and mechanical equilibrium equation. The simulation was done by assuming that the hydrogel was coated on unetched fiber and etched fiber. The strain induced at the fiber core was analyzed using finite element method. It was found that at the region near the jacketed fiber, the strain is distributed nonuniformly. The non uniform area for etched fiber is shorter than that of unetched fiber. The Bragg wavelength shift due to strain of the etched fiber is much larger than that of the unetched fiber.

Simulation of Fatigue Life Prediction and Enhancement of Connecting Rod of Car Engine

This paper investigates the fatigue life prediction and fatigue life enhancement of connecting rods of car engine. The fatigue life prediction was simulated by analyzing the stress occur in the connecting rod and then simulate the fatigue life prediction. The stress analysis was done by using finite element method. The results obtained from stress analysis is used as the input to simulate the fatigue life using stress-life method. The simulation was done for two models, the existing model and modified model. The modified model is the existing model with increased thickness in the highest stress region. The results show that the modified model has an improved fatigue life up to 231% compared to that of the existing model.

Analysis of pH Sensitive Hydrogel Coating Effect to Fiber Bragg Grating Properties for pH Sensor Application

This paper demonstrates the analysis of fiber Bragg grating properties due to hydrogel coating swelling effect. The modeling was done by simulating the hydrogel swelling behavior, and then carried out strain and stress analysis induced on the fiber due to hydrogel expansion. Meshless numerical method was adopted to solve the Poison Nernst Planck equation coupled to mechanical equation to simulate the hydrogel swelling. The hydrogel coating thickness was varied for 4 values, namely 30 μm, 40 μm, 50 μm and 60 μm. The strain and stress analysis were done numerically using finite element method. The results show that the strain on the fiber increases as the hydrogel coating thickness increased. The increase of hydrogel thickness results in the improvement of sensor sensitivity at the expense of stress value.

Design improvement of table fan blade in term of its vibration characteristic using finite element method

The main purpose of this paper is to improve vibration characteristic, which is natural frequency, of fan blade to get a good natural frequency. An existing table fan model TF1610 of three speeds with 16 inches blades was used for the study. To complete this study, finite element method has been used to perform the simulation and the analysis of the table fan blade. Components of the table fan are drawn using CATIA software. By using finite element software, the drawn table fan design was run for the analysis and the simulation to get the natural frequencies of the table fan blade and compared with the natural frequencies of the motor. The results show that, for Polycarbonate material, shape 4 is considered as the best shape. Shape 2 is considered as the best shape for Polyethylene Terephthalate and Polypropylene material.

Optimization of heavy duty truck chassis design by considering torsional stiffness and mass of the structure

The torsional stiffness is one of the most important properties of chassis that significantly affect its dynamic characteristics such as handling and rollover. The torsional stiffness is desired to be as high as possible since low torsional stiffness may cause resonance or vibration. There are several types of heavy duty truck chassis that used in Malaysia and no information about the torsional stiffness magnitude of it. In this work, the torsional stiffness of several existing types of heavy duty truck chassis and some modified types, namely: arc model, block model, hole model, multi holes model and fully block model are determined using finite element method. The torsional stiffness of several chassis was compared together with the weight comparison in order to get the best design of chassis that has high torsional stiffness and low weight. Based on the simulation result, the multi holes model is the best design due to the highest of torsional stiffness and the lowest mass.

Wall Thickness Optimization of High Powered Portable Multifunction Air Compressor Tank Using Finite Element Method

Air compressor tank is the important equipment in the automotive workshops and laboratories. Air compressor can be categorized as pressure vessel. Pressure vessel often has a combination of high pressure together with high temperature, in some cases of flammable fluids or highly radioactive material. Due to hazards, it is crucial to ensure there is no leakage on the products. In addition, vessel has to be design cautiously to cope with the operating temperature and pressure. The thickness of the PMAC should be optimized to get the best performance, the thickness cannot be very large due to the cost of material and exceeded weight and also cannot be very thin due to the failures caused by its internal pressure. In order to get the optimum thickness, finite element method software was used to simulate the stress analysis of PMAC with various thickness and various shapes.

Finite Element Stress Analysis of Optical Fiber due to Mechanical Expansion of Hydrogel Coating

This paper presents the stress analysis in optical fiber due to swelling of hydrogel material coated on it. The silica optical fiber was assumed to be coated by hydrogel that consists of hydroxyethyl methacrylate, acrylic acid and ethylene glycol dimethacrylate as crosslinker. The hydrogel swelling was modeled using free energy function. The conditional equilibrium of hydrogel was solved using finite element method and the stress induced in optical fiber was simulated simultaneously. The simulations were done for two hydrogel coating thickness values, 30 µm and 40 µm. Etched optical fiber coated by 40 µm hydrogel was also simulated. The results show that maximum stress in optical fiber is higher for thicker hydrogel thickness and is higher for etched optical fiber. Maximum stress magnitudes at all pH values are below tensile strength of optical fiber.