Masniezam Ahmad
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Preferred name
Masniezam Ahmad
Official Name
Masniezam, Ahmad
Alternative Name
Ahmad, Masniezam H.
Ahmad, M.
Main Affiliation
Scopus Author ID
56272606200
Researcher ID
IXE-4791-2023

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Engineering a Better Slice : Development of an Efficient Watermelon Slicing Tool

2025-06 , Mohd Uzair Mohd Rosli , Muhammad Syamil Zakaria , Masniezam Ahmad , Lim Jit Chao , Ng Chung Kit , Phong Jun Yuan

The Watermelon Slicer project focuses on the design and development of a mechanical tool to efficiently and safely slice watermelons. The objective is to address the challenges associated with manually cutting large and irregularly shaped fruits, which often pose difficulties in terms of safety, consistency, and time consumption. The proposed device integrates ergonomic design with sharp cutting mechanisms to achieve uniform slices with minimal physical effort. Key factors considered in the design include user safety, ease of use, material durability, and cutting precision. Prototypes were tested under various operational conditions to assess performance in terms of cutting efficiency, slice uniformity, and user comfort. Results demonstrate that the slicer significantly reduces preparation time while enhancing safety compared to conventional methods. The study concludes that the watermelon slicer presents an effective, time-saving solution for both domestic and commercial applications. Future work will involve further refinements to improve the product’s versatility for cutting a wider range of fruits and vegetables.

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Energy absorption and failure behavior of Al/CFRP/GFRP hybrid tubes under quasi-static axial loading

2023-07-01 , Fauziah Che Mat , Mohd Ridzuan Mohd Jamir , Masniezam Ahmad , Mohd Shukry Abdul Majid , Khairul Azwan Ismail

Fiber metal laminate (FML) is gaining increased interest among researchers in designing thin-walled tubes as an efficient energy absorber. The combination of aluminum tube and fiber-reinforced polymer (FRP) as an FML hybrid tube has successfully demonstrated enhanced crashworthiness performance of structures. Previous studies reported FML hybrid tubes employing a single type of FRP composite material as the laminate material. Investigations on the effect of stacking sequences of multiple types of FRP composite as laminate materials are limited and mostly focused on sandwich structures. This study aims to investigate the effect of reinforcement material as a laminate layer and stacking sequences on the crashworthiness characteristics of aluminum-FRP hybrid tubes under quasi-static axial compression loading. The crashworthiness characteristics and the failure behavior of aluminum monolithic tube, aluminum-single FRP material, and aluminum-multi FRP material hybrid tubes are tested and compared. Glass FRP (GFRP) demonstrates great potential as a laminate material for aluminum tube compared with carbon FRP (CFRP). Aluminum-GFRP and aluminum-GFRP-CFRP hybrid tubes exhibit a 26.4 % and 66.9 % increase in energy absorbed, respectively, compared with the monolithic aluminum tube. The specific energy absorption and crushing force efficiency of the aluminum-GFRP-CFRP hybrid tube show minimal reductions of 4.9 % and 6.2 %, respectively. GFRP is the better choice of laminate material for aluminum tubes compared with CFRP. Multiple FRP laminates show a larger crashworthiness enhancement of FRP hybrid tubes in achieving better crashworthiness performance of the energy absorber. These findings imply that the selection and stacking sequences of laminate material are vital in tailoring the performance of the hybrid tubes toward efficient energy absorbers.

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Computational Fluid Dynamics Analysis of Varied Cross-Sectional Areas in Sleep Apnea Individuals across Diverse Situations

2024-01-01 , Wan Mohd Faizal Wan Ab Rahim , Khor Chu Yee , Mohamad Suhaimi Shahrin , Muhamad Nur Misbah , Mohd. Hazwan Mohd. Hanid , Masniezam Ahmad , Mohd Haidiezul Jamal Ab Hadi

Obstructive sleep apnea (OSA) is a common medical condition that impacts a significant portion of the population. To better understand this condition, research has been conducted on inhaling and exhaling breathing airflow parameters in patients with obstructive sleep apnea. A steady-state Reynolds-averaged Navier–Stokes (RANS) approach and an SST turbulence model have been utilized to simulate the upper airway airflow. A 3D airway model has been created using advanced software such as the Materialize Interactive Medical Image Control System (MIMICS) and ANSYS. The aim of the research was to fill this gap by conducting a detailed computational fluid dynamics (CFD) analysis to investigate the influence of cross-sectional areas on airflow characteristics during inhale and exhale breathing in OSA patients. The lack of detailed understanding of how the cross-sectional area of the airways affects OSA patients and the airflow dynamics in the upper airway is the primary problem addressed by this research. The simulations revealed that the cross-sectional area of the airway has a notable impact on velocity, Reynolds number, and turbulent kinetic energy (TKE). TKE, which measures turbulence flow in different breathing scenarios among patients, could potentially be utilized to assess the severity of obstructive sleep apnea (OSA). This research found a vital correlation between maximum pharyngeal turbulent kinetic energy (TKE) and cross-sectional areas in OSA patients, with a variance of 29.47%. Reduced cross-sectional area may result in a significant TKE rise of roughly 10.28% during inspiration and 10.18% during expiration.

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Improved models for impact of Viscoplastic bodies

2018 , Masniezam Ahmad

Impact between two bodies is a complex phenomenon commonly occurs in many areas such as sports, automotive, geology and many more. Until now, modeling an impact is still a challenging task due to inherent imprecision of constitutive laws for the impact mechanics. Previously, impulse-momentum method was used as general principle to solve this dynamic problem. Then, impact is modeled by employing a lumped-parameter, which is represented by the spring and/or dashpot elements as a compliance at a small contact region around the point of contact. Through this method, the mechanics of contact during a short interval of impact event can be calculated. Formulation of the model using elastic, viscoelastic, elastoplastic or viscoplastic constitutive material behavior is employed as a contact law for the compliance at the small deforming region. At a very low impact velocity, an elastic model based on Hertz contact theory and the viscoelastic Hunt & Crossley model have accurately predicted impact responses. However, at higher impact velocities, a significant part of the initial kinetic energy is dissipated due to plastic deformation, stress wave propagation, sound, heat and other effects. An elastoplastic impact model can be used to predict the elastic-plastic deformation of the impacted bodies, however the effect of stress wave propagation is not considered in this model. This problem has been addressed by adopting a viscoplastic model that can predict the impact response which encompasses both elastic and plastic deformation and also considers the energy dissipated due to wave propagation. This study proposes two viscoplastic impact models that were developed from modification of previous viscoplastic models; Yigit and Ismail & Stronge models. The proposed model provides an alternative method to predict the impact responses by employing a linear spring element or combining a linear and nonlinear spring element in restitution phase of the compliance. The impact responses for several types of balls have been also studied by drop test experiments and finite element analysis. In experiment, various tests have been conducted to ensure accurate measurements of force and velocity for drops of different sports balls. On the other hand, an accurate finite element model (FE model) was developed and it was validated with previous FE model. As a result, the impact responses obtained from the proposed models have been validated with both experiment and FE analysis. In general, the proposed models can predict the maximum force and contact time with percentage error of less than 20 % and 11 % respectively. The proposed model was successfully improved the accuracy of impact response prediction for normal impact between two compact bodies. For the case of elastic impact, the proposed model gives the smallest energy loss of any of these previous models. Thus, it provides good estimation of contact forces and deformations, compared to the other viscoplastic models. Besides that, the impact responses for impact of different materials, sizes and impact velocities of the body have been obtained from the FE analysis. In overall, new developments for viscoplastic impact model and impact responses for colliding bodies were presented.

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Finite element analysis of proximal femur under static loading during sideway fall

2023 , Wong Kah Poh , Fauziah Che Mat , Fauzan Djamaluddin , Masniezam Ahmad , Nur Saifullah Kamaruddin , Ruslizam Daud , Ishak Ibrahim

A femoral fracture happens when the femur gains a very high stress concentration during fall and may results in femur fracture. In fact, most of fall-related cases occur in sideways fall. Bone fracture leads to life quality impairment and even life threatening. In this study, the effect of quasi-static loading on the femur bone during sideway fall is investigated by employing Finite Element (FE) software, ANSYS. The FE model is developed and simulated in the different fall conditions; inclination angle of 10° and rotation angle from -20° to 30°. The capacity of the bone is evaluated in terms of von Mises stress and deformation. The highest stress concentration is found at femoral neck region. 30° rotation angle with 10° inclination angle is observed as the critical loading direction at which the femoral neck may results in fracture. The understanding of the effect of loading magnitude and direction on the femoral bone capacity obtained herewith is useful in assisting the medical practitioner to provide better treatment and reduce repeated treatment cases.

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Multi-stage swirling fluidized bed: part 2 - the velocity distribution

2023 , Muhamad Silmie Mohamad Shabri , Mohd Al-Hafiz Mohd Nawi , Mohd Shahir Kasim , Muhammad Syamil Zakaria , Masniezam Ahmad , Mohammad Azrul Rizal Alias , Raja Muhammad Zulkifli Raja Ibrahim

This task involved numerical analysis study to investigate the air flow distribution affected by blade distributor arrangement of Multi-Stage Swirling Fluidized Bed (SFB). The current systems is in difference with conventional fluidization systems where the current systems will impart swirling motion to the particle. This study focused on the velocity distribution on blade distributor whereby the influence of blades number (30, 45, and 60) via horizontal inclination angle (10°, 12°, and 15) through multi-stage distributor arrangements, therefore a separate velocity component would be obtained. The numerical simulation, was utilised to compute and analyse the performance outcomes of three velocity components: tangential, axial and radial velocity in an Multi-Stage SFB. From the results of the study, the fluidization systems with high blades number of 60 and blades angle of 15° has shown a significant air flow distribution at both stages. Thus, the major velocity component such as velocity magnitude and tangential velocity in the Multi-Stage SFB have shown a retention uniformity along the radius blade distributor and the air flow inside the system rise more than 40 m/s.

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Energy Absorption Characteristics of Thin-Walled Tubes Filled with Rice Husk and Kenaf Fibers

2024-12-02 , Masniezam Ahmad , Khairul Azwan Ismail , Fauziah Che Mat , Mohd. Hazwan Mohd. Hanid , Ahmad Azraai Abd Aziz

This study investigates the energy absorption characteristics of thin-walled tubes filled with rice husk and kenaf fibers when compressed under axial compression. The aim of this study is to evaluate the crashworthiness parameters such as energy absorption (EA), initial peak load (IPL), crush force efficiency (CFE) and specific energy absorption (SEA). Experimental results show that tubes filled with rice husk and kenaf exhibit significant improvements in overall energy absorption compared to empty tubes. However, while both fillers enhanced EA, the SEA values were lower than predicted. Thus, it is suggested that further optimization, such as adjusting filler density or exploring hybrid filler combinations, could improve crashworthiness. This study highlights the potential for rice husk and kenaf fibers as sustainable filler options for lightweight, impact-resistant designs in automotive, aerospace, and other engineering applications, with opportunities for improvement in future research.

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Energy absorption characteristics of corrugated grooves thin-walled structure inspired by nautilus shell biological geometry

2025-01 , Mohd. Hazwan Mohd. Hanid , Safian Sharif , Masniezam Ahmad , Mohd Azlan Suhaimi , Khairul Azwan Ismail , Muhammad Syamil Zakaria

Crash box is a vital component for a vehicle in absorbing kinetic energy in the event of a road collision. The thin-walled structure is emerging as a favorable geometry in designing the crash box. This article investigates the energy absorption performance of the corrugated nautilus shell bio-inspired thin-walled structure made of AA6061-T6 aluminum alloy. This structure’s performance was evaluated using finite element analysis (FEA) under quasi-static and dynamic loading conditions in an axial direction, then validated by a quasi-static compression experimental test, which showed satisfactory agreement. The results show that the corrugated nautilus shell bio-inspired thin-walled structure integrated with corrugated grooves reduced peak crushing force (PCF) by 17.9% and increased specific energy absorption (SEA) by 1.3% and crush force efficiency (CFE) by 17.6% compared to non-corrugated design. It can be concluded that the proposed nautilus shell bio-inspired thin-walled structure integrated with corrugated grooves has the potential to replace conventional hollow square designs in vehicle crash box applications.

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Turning experiment of Ti-6Al-4V by using uncoated carbide insert

2020 , Muhamad Fitri Mahazer , Muhammad Syamil Zakaria , Masniezam Ahmad , Akmal Faris Shahbani

Titanium alloy Ti-6Al-4V is widely being used in the blades, discs, rings, airframes, fasteners, components, vessels, cases, hubs, forgings and biomedical implants. Nevertheless, the properties of titanium alloys which are low thermal conductivity, low modulus of elasticity and high chemical activity cause it very difficult to machine. Excessive elevated temperature due to low thermal conductivity of these alloys make it favorable for tool wear. In this paper, an experiment using orthogonal array L4 is conducted to explore the effect of cutting parameters e.g. cutting speed, depth of cut and feed rate in terms of surface roughness and tool wear. The cutting tool uncoated carbide is used in performing orthogonal cutting of Ti-6Al-4V in this study. It is found low cutting speed, feed rate and high depth of cut is favourable in producing good Ra and minimum flank wear.

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Modification of the design of circular thin-walled tubes to enhance dynamic energy absorption characteristics: experimental and finite element analysis

2020 , Masniezam Ahmad , Khairul Azwan Ismail , Mohd. Hazwan Mohd. Hanid , Fauziah Che Mat , A M Roslan

A thin-walled tube is an energy absorber device that functions to dissipate kinetic energy into another form of energy during impact. The design of thin-walled tubes is a significant factor which affects to the energy absorption characteristics. This paper provides a comparative study between the original thin-walled tube designs and several modified tube designs that have been proposed. The main objective is to improve the energy absorption characteristics, such as energy absorption capacity, initial peak load, specific energy absorption (SEA) and crush force efficiency (CFE). Throughout this research, aluminium alloy AA6061-T6 has been used as the material for all tubes. For comparison, all of the tubes are developed with a circular shape with the same diameter, thickness and length. In addition, they are also impacted at the same kinetic energy under dynamic axial loading. Validated LS-DYNA finite element (FE) models have been used to simulate the impact of the thin-walled tubes. Compared to the original tube design, the modified tubes have improved energy absorption characteristics. A conical tube with a flat end cap was identified as the best performing tube among the modified tubes because it had the lowest initial peak load, a moderate energy absorption capacity and an excellent CFE and SEA. The findings from this study can be used as a guidance in designing thin-walled structure.

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