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This paper aims to model the aerodynamic flow characteristics of NACA0010 for various angle of attacks including stall for incompressible flows using panel methods. This paper also aims to quantify the surface pressure distribution on streamlined bodies and validate the results with analytical Jukouwski method and inverse panel methods that can predict the aerodynamic flow behaviour using the geometric iteration approach.

The 2 D panel method was implemented in Qblade software v.06 which uses the fundamental panel method which rely on source strengths and influence coefficients to determine the velocity and pressure fields on the surface. The software implements the boundary layer or viscous effects to determine the influence on aerodynamic performance at various angles of attack. Jukouwski method is also evaluated for predicting aerodynamic characteristics and is based on the geometric iteration approach. Then complex aerodynamic flow potentials are determined based on the source strengths which are used to predict the pressure and velocity fields.

At low to moderate angles of attack, panel and Jukouwski methods predict similar results for surface pressure coefficients comparable to Hess and Smith inverse method. In comparison to panel method, results from the Jukouwski mapping method predicted the pressure coefficient conservatively for the same free stream conditions. With increase in Reynolds number, lift coefficient and aerodynamic performance improved significantly for un-tripped aerofoil when stall angle is approached when compared to tripped aerofoil.

This study demonstrated that panel methods have higher efficacy in terms of computational time or resources and thus can provide benefits to many real-world aircraft or aerospace design applications.

Even though panel and Jukouwski methods have been studied extensively in the past, this paper demonstrates the efficacy of both methods for modelling aerodynamic flows that range between moderate to high Reynolds number which are critical for many aircraft applications. Both methods have been validated with analytical and inverse design methods which are able to predict aerodynamic flow characteristics for simple bluff bodies, streamlined aerofoils as well as bio-inspired corrugated aerofoils.

This study aims to improve the mechanical properties of an object produced by fused deposition modelling with high-grade polymer.

The study uses an ensembled surrogate-assisted evolutionary algorithm (SAEA) to optimize the process parameters for example, layer height, print speed, print direction and nozzle temperature for enhancing the mechanical properties of temperature-sensitive high-grade polymer poly-ether-ether-ketone (PEEK) in fused deposition modelling (FDM) 3D printing while considering print time as one of the important parameter. These models are integrated with an evolutionary algorithm to efficiently explore parameter space. The optimized parameters from the SAEA approach are compared with those obtained using the Gray Relational Analysis (GRA) Taguchi method serving as a benchmark. Later, the study also highlights the significant role of print direction in optimizing the mechanical properties of FDM 3D printed PEEK.

With the use of ensemble learning-based SAEA, one can successfully maximize the ultimate stress and percentage elongation with minimum print time. SAEA-based solution has 28.86% higher ultimate stress, 66.95% lower percentage of elongation and 7.14% lower print time in comparison to the benchmark result (GRA Taguchi method). Also, the results from the experimental investigation indicate that the print direction has a greater role in deciding the optimum value of mechanical properties for FDM 3D printed high-grade thermoplastic PEEK polymer.

This study is valid for the parameter ranges, which are defined to conduct the experimentation.

This study has been conducted on the basis of taking only a few important process parameters as per the literatures and available scope of the study; however, there are many other parameters, e.g. wall thickness, road width, print orientation, fill pattern, roller speed, retraction, etc. which can be included to make a more comprehensive investigation and accuracy of the results for practical implementation.

This study deploys a novel meta-model-based optimization approach for enhancing the mechanical properties of high-grade thermoplastic polymers, which is rarely available in the published literature in the research domain.

This study aims to investigate the mechanical, thermal and water absorption (WA) properties of kenaf fiber (KF) composites hybridized with powdered Acacia concinna pods (ACP).

Kenaf fiber reinforced epoxy polymer hybrid composite was fabricated using several weight percentages of ACP powder as filler (0%, 2%, 4%, 6% and 8%), both with and without chemically altering the fiber mat. 6 Wt.% NaOH was used in distilled water to treat KF mat chemically. The hand layup technique is used to produce ASTM-compliant KF hybrid laminates. Tensile, flexural and IZOD impact strengths were tested on the generated hybrid composites and their thermal and WA characteristics. Scanning electron microscope fractography revealed that fiber pulling-out, debonding and cracking were the main ways composites fractured.

The investigation findings reveal that the tensile, flexural and impact strengths increased when ACP fillers were added up to 4, 6 and 8 Wt.%, respectively. Thermogravimetric analysis indicates that the hybrid composite is thermally stable up to 215°C. WA experiments reveal that KF mat composites treated with 0 Wt.% ACP filler had less WA than those not treated with ACP filler. The treated KF with 4% filler hybrid composite demonstrated improved interfacial bonding between the reinforcement and matrix compared to other combinations.

Although filler made of A. concinna is inexpensive, lightweight, renewable, totally or partially recyclable and biodegradable, its potential application in hybridizing composites is yet to be investigated. Hybridizing the KF mat with ACP filler in an epoxy matrix produced novel hybrid composites. Evaluations have been conducted on the effects of ACP filler on the mechanical, thermal and WA characteristics of composites.