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Utilizing Model-Based Systems Engineering (MBSE) for Tailoring an Islamic Values-Based Sounding Rocket Development Cycle

This paper presents a novel life cycle model for developing university-scale sounding rockets, integrating technical and Islamic perspectives. The model, referred to as the 'Water Spring Model,' aims to align aerospace engineering processes with systems engineering (SE) phases and integrate Islamic values such as Itqan (perfection in work), Shura (consultation), and Jihad (intellectual struggle). The model was successfully applied in a small project that reached the simulation stage, providing a comprehensive framework connecting life cycle phases with the Aerospace Vehicle Design (AVD) process in a unified diagram. Despite the project's limited scope, the model was found to be beneficial for fostering a holistic understanding among team members and connecting their work to motivating values. Feedback highlighted the need for improved governance, cross-departmental communication, and the integration of unified project models. Future work will detail the model's processes and further integrate Tafsir and Fiqh methodologies. This initial application suggests that the model has potential for broader use in similar projects within Islamic countries, offering a balanced approach that enhances both project outcomes and team motivation.

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Prediction of Pressure Coefficient for SACCON Wing using Artificial Neural Network

This study explores the application of artificial neural networks (ANN) for predicting the coefficient of pressure (CP), an essential parameter in aerodynamic studies, on the SACCON wing. Traditional methods such as computational fluid dynamics (CFD) and wind tunnel tests have several drawbacks, including high computational cost, time consumption, and inconsistent data. To address these issues, this study proposes a multi-layer perceptron (MLP) neural network as an alternative. The training data for the ANN is derived from previously conducted wind tunnel experiments on the SACCON wing. The network's structure includes three hidden layers and employs the Levenberg-Marquardt backpropagation algorithm for weight updates. Data pre-processing involves normalization, and the dataset is split into training, testing, and validation sets. The results indicate that the ANN can capture general trends in CP data. However, it struggles with detailed and irregular predictions specifically in predicting tip vortex and suction peak, leading to underfitting, partly due to a lack of sufficient training data at location where vortex interaction occurred. The optimal network configuration includes a learning rate and regularization parameter of 1 x 10^(-5) and hidden layers containing 10, 10, and 3 neurons, respectively. Despite achieving reasonable performance metrics (RMSE = 0.1555, R-value = 0.9855, R^2 = 0.9711), the network's predictions on new data are less accurate due to underfitting. Future improvements suggest increasing the training dataset size or enhancing feature engineering to improve the ANN's predictive capabilities. Additionally, using ANNs during the testing phase can reduce time, manpower, costs, and the number of data points required to define aerodynamic performance.

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Effects of Reynolds Numbers on Aerodynamic Performance of Large Wind Turbine Blades

This study investigates the aerodynamics of the IEA-15MW-240 wind turbine that is using W3-FFA airfoil family by developing a comprehensive airfoil database that includes a wide range of Reynolds numbers instead of the traditional use of a single representative Reynolds number in aerodynamic modeling. A new airfoil database, including aerodynamic coefficients across a wide range of Reynolds numbers, has been developed. Subsequently, the AirfoilPrepy is used to correct the 3D effects and calculate the full range of angles of attack (-180 to +180 degrees) on the rotor blades. This new database is integrated into the OpenFAST simulation tool to replace the conventional database that uses the representative values. This approach could enhance the accuracy of predicted aerodynamic behavior along the blade span, factoring the effect of Reynolds number distribution on the resultant blade performance characteristics. Overall, the results indicate some improvements in the results of the performance predictions and aerodynamic loads of the wind turbine, especially with turbulent wind field. The findings underscore the importance of considering Reynolds number distribution in the aerodynamic analysis and also when designing wind turbine blades to optimize performance.

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Experimental Aerodynamic Drag Analysis of Parachute Systems for UAVs: Impact from Number and Length of Suspension Lines

Unmanned Aerial Vehicles (UAVs) are widely employed in a variety of applications, but ensuring safety and easing disaster recovery is a significant concern. This project aims to provide a dependable parachute system for small drones, addressing challenges such as the drag force produced and instability during emergency landings; i.e. the impact from the number and length of suspension lines. The project intends to create a parachute system that takes drag force into account to lessen fall speed during an emergency. Wind tunnel tests examined the aerodynamic drag performance of the parachute design (diameter of 60 cm) at Reynold’s Number ranging from 80k to 330k. Two design factors were investigated: the number and length of suspension lines. The study revealed that the drag coefficient is greatest at wind speeds of 7-8 m/s, and the effective area of a fully developed parachute is a crucial factor to consider. The findings conclude that longer and fewer suspension lines result in a lower falling rate during emergency landings.

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An Optimization Study for Permeability Behavior of Woven Flax Fabrics in Vacuum Infusion Process using Flow Analysis Approach

Permeability is a key factor influencing the quality of composite products, particularly when dealing with woven fabric reinforcement in various patterns and stacking sequences. Both material and processing factors influence the performance of composites fabricated using the vacuum infusion method. Therefore, understanding and optimizing the combination of these factors is crucial. This study applies Taguchi's approach to determine the optimal materials and process factors using a simulation method. An L9 (3^2) design of experiments with two factors at three levels is investigated, varying between 4, 8, and 12 plies of woven fabrics at three inlet pressures of 80, 90, and 100 kPa. The results show a significant effect of these factors on permeability values, with a rising trend in permeability observed as the number of plies in woven flax fabric composites increases. This increase in permeability is primarily due to greater void volume, inter-ply gaps, improved connectivity, and reduced compression. This optimization is established as a baseline to conduct further experiment of permeability study using flow analysis approach.

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Thermodynamic Analysis of Air Cycle Machine for Aircraft Cabin Thermal Comfort at Different Flight Segments

In the past few decades, the aviation industry has been growing rapidly. Subsequently, demand for thermal comfort inside the cabin of the aircraft has also been on the rise. Maintaining the cabin at a temperature and pressure that will guarantee the comfort and safety for all crew and passengers during the whole flight operation is the primary function of the cabin air conditioning and pressurization system. Air cycle machine (ACM) is a reliable method that has long been the basis of aircraft's cabin air conditioning since the air is free, safe, and abundant. Therefore, it seems crucial to identify and understand the design conditions at each flight segment. To do this, this study determines the work in turbine and compressor of the ACM for maximum performance and estimate the cooling load at every flight mission by evaluating the coefficient of performance (COP) with and without pressurization work. The simulation results show the COP, as well as the cooling load, at different flight segments and it has been found that the most efficient phase is the cruising phase with COP at 0.15 and COPP at 0.14. In addition, the effects of the environment, including variations in pressure, temperature and altitude, on the system's network and how the air cycle machine performs are also observed in this study.

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Optimal Variable PID Control Tuning for the Baseline-X Blended Wing-Body Aircraft Design

Development of aircraft design has shifted towards several innovative configurations such as blended wing-body (BWB) design, which integrates the fuselage and wings into a single, smoothly blended structure for enhanced aerodynamic efficiency. Nevertheless, this tail-less configuration also poses challenges in terms of stability and controllability of the aircraft. To address the issue, this research investigates the effect of PID control on the cruising aerodynamic coefficients of a BWB aircraft design called Baseline-X, which is developed by Flight Technology & Test Centre (FTTC) UiTM Shah Alam. This paper also analyses its trim maximum lift-to-drag ratio and evaluates its key performance parameters. Virtual flight tests are conducted using X-Plane 11 flight simulation software, where flight data are analyzed to determine the maximum lift-to-drag ratio and the PID coefficient values that ensure Level 1 longitudinal flying qualities as per MIL-F-8785C standards. Performance parameters including cruising speed, rate of climb, endurance and range are further evaluated using spreadsheet suite. The result demonstrates successful application of PID control in managing the longitudinal stability of Baseline-X BWB aircraft. The optimal PID coefficients for this BWB design, along with its cruising speed, climb rate, endurance and range, are obtained while at the same maintaining the damping ratio of 0.76 for phugoid and 0.36 for short-period oscillations.

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Investigation on the Regression Rate of Additively Manufactured Polylactic Acid Nested Skeleton for Hybrid Rocket Motor

The low regression rate of conventional hybrid rocket motors (HRM) poses a significant challenge in the field. Due to its high regression rate, Paraffin wax has emerged as a promising hybrid rocket fuel. In this study, a 3D-printed skeleton is embedded within the paraffin grain to act as a secondary fuel while enhancing the mechanical properties of the fuel. Different types of skeletons utilising various infill designs available in 3D-printed slicer software employing PLA material were examined. The objective of the research is to evaluate the performance of armored grain with honeycomb, gyroid, and concentric designs PLA skeleton analytically using the internal ballistic model and static firings for the determination of thrust, regression rate, and specific impulse while comparing the ballistic response of the armored grains to that of pure paraffin-based fuels. The result shows the embedded skeletons significantly improved the regression rate of the paraffin fuel. The concentric PLA skeleton increased the regression rate by approximately 48.28%, achieving 1.29 mm/s, while the gyroid and honeycomb designs resulted in increases of 40.23% and 20.69%, respectively. Additionally, all PLA skeletons improved performance parameters compared to pure paraffin wax, with the concentric design showing a 28% increase in thrust (67.27 N vs. 60.3 N).

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Aerodynamics Performance of UiTM's RC Flying Wing using CFD Simulations

This paper presents the aerodynamics forces data for the UiTM's radio-controlled (RC) flying wing, obtained through the computational fluid dynamics (CFD) simulation. The CFD simulation analysis is done using the Ansys Fluent software. The flying wing structure comprises a Clark Y airfoil configuration, which is known for its high stability at low Reynolds number (Re) and significant lift-to-drag ratio (L/D) capability. The Spalart-Allmaras (S-A) model is used as the turbulence model because of its efficiency in modeling turbulence in subsonic flow based on the iteration and computational time compared to other turbulence models. The simulations are carried out at various angles of attack, α from -10° to 38°, aerodynamic characteristics of the RC flying wing are simulated, which include lift (L), drag (D), and lift-to-drag ratio (L/D). From the simulation results, it is found that the aircraft achieves its maximum lift coefficient, C_(L,max) of 1.762 at the angle of attack of 30° and its minimum drag coefficient, C_(D,min) of 0.045 at the angle of attack of -2°. The maximum L/D is at 10.76 and the angle of attack of 6°. The simulation results from this study serve as the reference basis to improve this flying wing in the future.

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Corrosion Effects on Low Cycle Fatigue (LCF) Life of Aluminum 2024-T3

The environmental conditions in Malaysia contribute towards material deterioration. High humidity, salty environment and high temperature are the main conditions that provide a corrosive environment throughout the year as stipulated in the MIL-STD-810H standard. In general, flight operation for the Royal Malaysian Air Force (RMAF) greatly exposes their military aircraft to cyclic loading and fatigue under corrosive conditions. For fighter aircraft, the fatigue life design is often based on the Low Cycle Fatigue (LCF). Meanwhile, the study of corrosion fatigue is unique depending on location and complexity. Based on this notion, this study aimed to investigate the impact of corrosion on LCF life of Aluminum 2024-T3. The aluminum specimens first underwent tensile test to determine their static mechanical properties according to ASTM E8M. Some specimens were then exposed to Salt Spray Chamber Test, which induced the corrosive and salty environment according to ASTM B117, for intervals of 48, 96, 144 and 168 hours. At every interval, several specimens were removed and sent for the LCF Test at strain amplitudes of 3.3%, 5.0%, 6.7% and 11.0%. The results revealed a significant decrease in LCF life for corroded specimens compared to non-corroded specimens. Interestingly, the effect of corrosion on the LCF life became less noticeable at high strain levels, suggesting that post-yielding buckling modes took precedence as the dominant failure mechanism.