Fairuz Izzudin Romli

Optimization of a synthetic jet actuator for flow control around an airfoil

This paper deals with the optimization of a synthetic jet actuator parameters in the control flow around the NACA0015 airfoil at two angles of attack: 13° (i.e. the stall angle of NACA0015) and 16° (i.e. the post stall angle of NACA0015) to maximize the aerodynamic performance of the airfoil. Synthetic jet actuator is a zero mass flux-active flow control device that alternately injects and removes fluid through a small slot at the input movement frequency of a diaphragm. The movement of the diaphragm and also the external flow around the airfoil were simulated using numerical approach. The objective of the optimization process function was maximum lift-drag ratio (L/D) and the optimization variables were jet frequency, length of the jet slot and jet location along the chord. The power coefficient of the jet was considered as a constraint. The response surface optimization method was employed to achieve the optimal parameters. The results showed that the actuator is more effective for post stall angles of attack that can lead to an enhancement of 66% in L/D.

Design and mechanical analysis of a 3D-printed biodegradable biomimetic micro air vehicle wing

The biomimetic micro air vehicles (BMAV) are unmanned, micro-scaled aircraft that are bio-inspired from flying organisms to achieve the lift and thrust by flapping their wings. There are still many technological challenges involved with designing the BMAV. One of these is designing the ultra-lightweight materials and structures for the wings that have enough mechanical strength to withstand continuous flapping at high frequencies. Insects achieve this by having chitin-based, wing frame structures that encompass a thin, film membrane. The main objectives of this study are to design a biodegradable BMAV wing (inspired from the dragonfly) and analyze its mechanical properties. The dragonfly-like wing frame structure was bio-mimicked and fabricated using a 3D printer. A chitosan nanocomposite film membrane was applied to the BMAV wing frames through casting method. Its mechanical performance was analyzed using universal testing machine (UTM). This analysis indicates that the tensile strength and Youngs modulus of the wing with a membrane is nearly double that of the wing without a membrane, which allow higher wing beat frequencies and deflections that in turn enable a greater lifting performance.

Personal air vehicle (PAVE) application in Malaysia

Transportation has become a huge necessity in our life today, which is instrumental to create greater socioeconomic opportunities. As the world progresses, transportation systems will undergo paradigm shifts to suit with changing requirements. Personal transportation is often preferred to the public transport and to date, most of them have been made on the ground through roads. However, with the increasing traffic volume, the average time spent travelling on roads has significantly increased for the same amount of distance travelled. It has already been proposed that utilization of the possible third dimension of transportation system, which is the air transport, can facilitate in supporting the personal transportation and subsequently alleviate this problem. This notion gives birth to the design concepts of the personal air vehicle (PAVE) that is envisioned to operate synergistically with ground and air infrastructures. This paper aims to preliminarily study and analyze the potential benefits of having PAVE option in Malaysia for domestic travel and how its performance will fare in comparison to the existing ground transportation options. The results of travel time and cost comparisons highlight the potential of PAVE application for the domestic transportation in Malaysia, particularly for personal travel need.

Computational Approach in Sizing of Pulsejet Engine

Research in pulsejet has intensified recently due to its design simplicity that can be developed into efficient small scale propulsive units for new applications such as UAVs and Unmanned Combat Vehicles (UCAV). A major obstacle for its development is low efficiency of the engine. The objective of this research is to investigate the possibility of using pulsejet in certain applications where the pulsejet can trade its low efficiency with low cost, simple design, and light weight. Numerical analysis is used for analysing the pulsejet engine design. The main results drawn from this research is in increasing efficiency and improving performance of engine by improving size of engine, especially diameter of combustion chamber. The computed results show good resemblance with published data.

Conceptual Design of Flapping Wing Using Shape Memory Alloy Actuator for Micro Unmanned Aerial Vehicle

Micro Air Vehicle (MAV) has the capability to fly autonomously in complex environments which enables human to conduct surveillance in areas which are deemed too dangerous or in confined spaces that does not allow human entry. Research and development of MAVs aim to reduce their size further, thus novel techniques need to be explored in order to achieve this objective while still maintaining the MAVs’ current performance. In this paper, a conceptual design of an MAV with a main drive system using shape memory alloy (SMA) actuator to provide the flapping motion is proposed. SMA is considered superior to other smart materials due to its efficiency and large energy storage capacity. By incorporating SMA in the flapping wing MAV, it will provide users the flexibility to add more payloads by reducing bulky cables or reduce operating cost by using less fuel. However, there are some drawbacks in using SMAs such as nonlinear response of the strain to input current and hysteresis characteristic as a result of which their control is inaccurate and complicated.

Conceptual Aircraft Design Exploration through Functional Approach

In today’s market, it is no longer sufficient to have better designs than the competition. In order to maximize the product’s market potential, it has to be rapidly produced and made available to the market. To reduce their time-to-market period, manufacturers need to shorten their design and development process. It becomes vital that the design architecture solution is derived faster, which can be handful for complex products like an aircraft with the current geometrical-based approaches due to the plethora of physical alternatives to be considered. On the other hand, the search for design architecture solution from functional requirements is theoretically more effective because functional space is comparatively smaller than physical search space. This allows the design efforts to be more focused and this subsequently saves time, efforts and resources. With this notion, there is a driving motivation to adapt functional approaches into the conceptual product design process in order to exploit some of its advertised benefits. In this paper, an example case study of an aircraft conceptual development is presented to highlight possible advantages of approaching architecture solutions from the functional space.

Identification of Modal Properties of Composite Thin Plate Using OMA in Wind Tunnel Environment

Identification of modal parameters is crucial especially in aerospace applications whereby the interactions of airflow with aircraft structures can result in undesirable structural deformations. This structural deformation can be predicted with knowledge of the modal parameters. This can be achieved through conventional modal testing that requires a known excitation force in order to extract these dynamic properties. This technique can be experimentally complex because of the need for artificial excitation and it also does not represent actual operational condition. The current work presents part of research work that address the practical implementation of operational modal analysis (OMA) applied to a cantilevered hybrid composite plate exposed to low speed airflow in a wind tunnel. A single contactless sensing system via a laser vibrometer is employed to measure the response. OMA technique applied in a wind-on condition succeeded in extracting the modal parameters of the hybrid composite plate which correlate well with modal testing using impact hammer excitation.

Conceptual Product Design Methodology through Functional Analysis

Due to high competitive nature of todays product market, it is essential for conceptual design architecture solution to be derived faster while still maintaining a certain level of innovation to differentiate it from other competing products. This can be a handful task for the development of complex product designs with the current geometrical-based approaches due to plethora of possible physical alternatives to be considered. The search for product design architecture solutions from its functional requirements is more effective as the functional space is comparatively smaller than the physical search space. This allows the design and development effort to be more focused and saves time and resources. With this notion, there is a driving motivation to adapt the functional approach into the conceptual design process to exploit some of its benefits. In this paper, a methodology to derive the product architecture solution from functional approach is discussed and proposed.