Mohd Noor Arib Md Rejab
Thumbnail Image
Preferred name
Mohd Noor Arib Md Rejab
Official Name
Mohd Noor Arib , Md Rejab
Alternative Name
Rejab, Mohd Noor Arib
Rejab, M. N. Arib
Rejab, M. N. A.
Main Affiliation
Scopus Author ID
55982324600
Researcher ID
GDQ-2664-2022
INM-7628-2023

Research Output

Filters

6 1
2
6
Reset filters

Settings
Now showing 1 - 6 of 6
Thumbnail Image
Publication

Suppresion of sommerfeld effect in power transmission system employing cardan shaft through phase angle arragement

2024-07-01 , Omar M.H. , Muhajir Ab. Rahim , Mohd Noor Arib Md Rejab , Rani M.N.A.

In a power transmission system with a cardan shaft, the Sommerfeld effect occurs, which is characterized by speed capture and release at the resonance range. Suppression of the Sommerfeld effect is critical for smooth and reliable operation. This study aims to suppress the Sommerfeld effect in a transmission system by compensating the phase angle between the two universal joints installed in the cardan shaft. The differential equations of motion representing the dynamics of the system are derived using the Lagrange equation. The responses are simulated numerically using the Runge–Kutta algorithm for scenarios with constant and gradually varying input torque. To suppress the Sommerfeld effect, the phase angle is set to 25%, 50%, 75% and 100% of the maximum twist angle observed in the subcritical speed range of the in-phase configuration. With the phase angle of 25%, the Sommerfeld effect is damped, where the output speed only deviates by 5% from the estimated value for both input torque scenarios. It is shown how the change of the phase angle attenuates the Sommerfeld effect and the system vibrations, which should be considered in the development and practical implementation.

View
Thumbnail Image
Publication

Numerical Study on the Torsional and Lateral Vibrations of Double Universal Joint Driveline System

2023-01-01 , Omar M.H. , Muhajir Ab. Rahim , Mohd Noor Arib Md Rejab

Utilizing a universal joint can lead to significant vibration within a driveline system. This study presents a model for analyzing the torsional and lateral vibrations of a driveline connected by a double universal joint. The governing equations of motion are derived, and the Runge-Kutta method computes steady-state responses across a spectrum of input rotational speeds. The focus is to examine the effect of system parameters, including static angular misalignment, load torque, and lateral stiffness. Relative amplification is used to analyze the effects of parameters on system vibration. Results indicated that the second-order component of input rotational speed induced by the universal joint was the factor that caused the vibrations. For the considered system, static angular misalignment significantly impacts both the torsional and lateral vibrations. Increasing the angular misalignment from 15° to 30° results in a threefold increase in lateral vibration amplification, while torsional vibration amplification is increased by nearly two times. The effect of load torque is almost linearly proportional to torsional vibration but is nonlinear to lateral vibration. Thus, lateral vibration is significantly impacted compared to torsional vibration for higher load torque. Changing the stiffness leads to a modification of the natural frequency. Increasing the lateral stiffness shifts the critical speed to a higher speed range, resulting in reduced lateral vibration amplitude. It is demonstrated that a slight fluctuation in angular misalignment due to lateral vibration will not affect the torsional vibration even if both vibrations are coupled. The findings may enhance understanding of how changing system parameters affects vibration.

View
Thumbnail Image
Publication

NUMERICAL STUDY ON EFFECT OF PHASE ANGLE ON TORSIONAL AND LATERAL VIBRATIONS IN POWER TRANSMISSION SYSTEM EMPLOYING CARDAN SHAFT

2023-07-01 , Omar M.H. , Muhajir Ab. Rahim , Mohd Noor Arib Md Rejab

A power transmission system driven by a Cardan shaft may experience severe vibration due to fluctuating rotational speed and moments transferred to the final drives, determined by the level of angular misalignment and phasing of the joint yokes. This study investigates the potential of an out-of-phase position displaced by a phase angle in attenuating vibrations. The governing equations representing the dynamics of the system are derived. The torsional and lateral vibration responses are numerically calculated over a range of input rotational speeds. When attenuating the vibration, the phase angle is set equal to the maximum twist that occurs during the in-phase position. Relative attenuation is used to investigate the phase angle effects. The effectiveness is studied for different levels of static angular misalignment. For the considered system, the results showed that for static angular misalignment greater than 20 degrees, the proposed phase angle arrangement could attenuate torsional vibration by more than 10 percent and significantly attenuate the lateral vibration.

View
Thumbnail Image
Publication

Characterization of Hardening Duffing Oscillator based on a Tensioned Wire System

2021-06-11 , Muhajir Ab. Rahim , Mohd Shuhanaz Zanar Azalan , Mohd Noor Arib Md Rejab

In this paper, the characterization of mechanical system that behaves as a hardening Duffing oscillator is presented. This mechanical system comprises a mass attached to a tensioned wire which exhibits a hardening stiffness behavior when the displacement of the mass is large. Firstly, the equation of motion of the system is derived to provide the relationship between the applied static force and the resulting displacement. Then, the effect of initial tension, and number of the wires on the force-displacement relationship are analyzed. It has been found that a higher tension will produce higher linear stiffness, whilst having a negligible effect on cubic stiffness. Moreover, the nonlinearity is less sensitive for small inequality between the length of wire on the left and right side of the mass. The results presented herein provide an insight of the system behavior for its application as a vibration isolator.

View
Thumbnail Image
Publication

The behavior of Projectile Ricochet off various wooden targets

2006 , Mohd Shukry Abdul Majid , Robert S. Birch , M.I. Jais , Mohd Noor Arib Md Rejab , Hafizawati Zakaria

This paper details the assessment of bullet ricochet as a function of incident angle and the impact plate material. A series of experimental testing have been carried out on three different woods chosen to give range of hardness, ranked from the hardest to softest. Each wood was fired upon varying angles of incidence until ricochet was observed. The tests were conducted in an indoor short range using a standard 0.22 calibre bolt-action rifle. In general, the ricochet angle was found to increase with an increase in angle of incidence but decrease with an increase target hardness.

View
Thumbnail Image
Publication

Numerical Study on Effect of Phase Angle on Torsional Vibration in Double Cardan Joint Driveline System

2023-11-09 , Omar M.H. , Muhajir Ab. Rahim , Mohd Noor Arib Md Rejab , Rani M.N.A. , Mutra R.R.

A driveline system with a double Cardan joint may be subject to severe vibration due to fluctuations in angular speed determined by the degree of angular misalignment and the phasing of the joint yokes. The inner yokes of the two joints are usually in the same plane or in phase. In this study, the potential of an out-of-phase position displaced by a phase angle to attenuate torsional vibration of the driveline is investigated. The governing equations describing the torsional dynamics of the system are derived. The torsional vibration is indicated by a maximum and minimum value of the steady-state twist calculated over a range of input rotational speeds. When attenuating the vibration, the phase angle is set equal to the maximum twist that occurs during the in-phase position. Relative attenuation is used to study the percentage of attenuation of the twist due to phase angle effects. The effectiveness is investigated for different levels of angular misalignment. For the system considered, the results showed that the phase angle can attenuate the torsional vibration by more than 10 percent for angular misalignment greater than 20 degrees.

View