Vol: 1 Issue: 1
Finite Element Modeling and Evaluation of Ceiling Fan Blades Using Wood as Alternative Engineering Material
Simon Ogbeche Odey and David Olusola Fakorede
1. INTRODUCTION
Fans are widely used for circulating air for the purpose of cooling in rooms, buildings, agricultural machineries, mechanical, electrical and electronic gadgets to create a more comfortable atmosphere. Air flow are created using fans in fluids - liquids and gases. Fan consists of a rotating arrangement of vanes or blades which act on the fluid by pulling or pushing it [1]. Reports have showed that the cost of metals and plastics generally are becoming higher than wood as construction materials leading to high market prices of products [2]. Utilization of available, cheap and durable wood as replacement for ceiling fan blades would definitely lead to products availability, accessibility and affordability.
Fans are specifically used in circulating air for the purpose of cooling in buildings, agricultural machineries, mechanical, electrical and electronic gadgets to create more conducive environment. Most postharvest crops processing and storage equipment utilize fans for their effective operations. Fans creates flow within a fluid such as liquids and gases. Axial flow fan creates air flow linearly along the axis rotation. Thus, forcing air to move in parallel to the shaft for cooling, compression and ventilation [3]. The rotating assembly of blades and hub is known as an impeller, a rotor, or a runner [1]. Generally, fan blades will always rotate when placed in the direction of flow of a fluid, however, such does not produce enough airflow relevant to provide cooling system. Metals and plastic materials are readily used in the design of fan blades. Reports show that the cost of metals and plastics generally are becoming higher than wood as construction materials [2].
Wood is the oldest, cheapest and most widely used engineering materials. It is the only significant building material that is grown [4], renewable and readily available in all parts of the globe. In Nigeria, wood is available in almost all the geopolitical zones. It is durable and performs creditably well when properly treated. Wood is cheaper than other materials like metals, plastics, composites and alloys used for the design of fans and other devices [5].
ANSYS and SOLID WORKS software enables the utilization of Finite Element Analysis (FEA) for predicting how a product reacts to real-world forces [6]. Finite element modeling (FEM) makes it possible for the analysis of complex engineering problems. It allows full 3D simulation without compromising the geometrical details. Wood, the oldest and most widely used engineering materials is the only significant building material that is grown [4]. It is renewable and readily available throughout the world. In Nigeria, wood is available in almost all the geopolitical zones. Wood has high ratio of durability and performance when properly treated. It is considerably cheaper than other materials like metals, plastics, composites and alloys used for the design of fans and other devices [5]. Utilization of wood in fans development is scarce. Hence, there is great necessity in the use and application of wood in the design and production of fan blades to reduce cost and optimized production.
Finite Element Modelling (FEM) permits complex analysis of multilayered complex shape structures, including stress–strain, dynamic, thermal, or electro-magnetic loading. Finite Element Analysis (FEA) is a computerized method for Predicting how a product reacts to real-world forces, vibration, heat, fluid flow, and other physical effects [6]. FEM applications include stress analysis, slope stability analysis, seepage of fluids in soils and rocks, analysis of dams, tunnels, bore holes, propagation of stress waves and dynamic soil structure interaction. ANSYS and SOLID WORKS software package based on the finite element analysis, enable 3D simulation without compromising the geometrical details [7]. ANSYS is used to determine how a product will function with different specifications, without building a prototype or conducting crash tests [8].
[9] studied experimental and CFD/FEA simulation of large axial fan effect on flow. The flow pattern is changed by adding a radiator in front of axial fan. However, it produces around 10 to 20 percent stresses on the blade surface. [10] made an effort to find the best thermal comfort level with the combination of air-conditioners and ceiling fans. A two dimensional steady state problem was solved using CFD simulation. Fourteen different simulation cases were run for different locations of inlet diffuser and the position of the fan. Momoi and Sagara et al. (2004) studied the velocity profile of a ceiling fan in an air-conditioned room. CFD results show greater value of velocity profile near the rotational centre of the ceiling fan. [11] developed a new approach for installation of ceiling fans that have an enclosed housing and is hidden inside the ceiling floor. Using experimental and numerical methodology, the flow behaviour is predicted with different operating conditions and geometric housing. Conclusions revealed that as air moves towards the floor, different flow patterns are generated and demonstrate “inhale-return” phenomenon only when housing comprises of anomalous shaped high ring-plate and outlet-inlet ratio. [12] experimentally compared the composite materials fan blades with aluminium fan blades. Results show that composite blade save 34% fabrication cost and 30% power because of 28% weight reduction.