Development of Ceiling Fan Components using Glass Fiber Composites

Transcription

1 Development of Ceiling Fan Components using Glass Fiber Composites Senthil Kumar S 1, Riyaz Haja Mohideen.S 2,Sarath Babu.M 3, Ram Kumar.M 4, Soundar.K 5 1,2,3,4,5 Department of Mechanical Engineering, R.M.K College of Engineering and Technology, Chennai, India. Abstract Energy crisis is the major problem faced widely. Though wide range of researches is being laid in the areas of alternate energy sources, proper management of the available energy sources will contribute in controlling this energy crisis, particularly in high populous countries such as India. Ceiling fan being one of the vital electric appliance, consumes considerable electric power in most domestic and Industrial application. Imparting fibre reinforced composite in ceiling fans reduces the weight of the fan, thereby considerably reducing the power consumption. In this work the fabrication of composite ceiling fan made up of glass fibre reinforced polymer is carried out and the performance of this fan is compared with the conventional fans. Compared to existing ceiling fan, the composite fan saves 26% of power, and reduces the cost by 28%. The weight is reduced by 27% thus reducing the power consumption. It is also determined that the flow velocity through the composite fan is 15% more than that of the conventional fan. I. INTRODUCTION A ceiling fan is a device hanging from the ceiling of a room. Ceiling fans utilize hub-mounted rotating paddles in order to produce a cooling effect as a result of air circulation. The circulation of air creates a wind-chill effect that makes a person feel cooler. The ceiling fan blades are usually made up of aluminium, steel, wood, etc. The ceiling fans have become a common appliance both in domestic and industrial applications. Though the power consumed by these fans is less, it is to be considered that these fans run on a continuous duty and this makes the power consumption significant. Energy crisis and less availability of natural resources being the major challenge, selection of better material and effective manufacturing processes, can reduce both the power consumption and the manufacturing cost. Composite materials have found a wide range of 211 application in replacing the conventional materials with enhanced strength and mould ability. Composites are compound materials, differ from alloys in the fact that individual components retain their characteristics but are so incorporated into composites so as to take advantages only of attributes, not that characteristics of short comings, to obtain improved materials. Composite materials (also called composition materials or shortened to composites) are materials made from two or more constituent materials with significantly different physical or chemical properties, that when combined, produce a material with characteristics different from the individual components. The individual components remain separate and distinct within the finished structure. Properties of composites are strongly influenced by the properties of their constituent materials, their type, their distribution and the interaction between them. Like conventional materials, composites are not homogeneous and isotropic. Composites are generally completely elastic up to failure exhibit no yield point or a region of plasticity. At present aluminium is widely deployed in blade manufacturing mainly due to the advantages such as less density compared to steel, corrosion resistance and aesthetic look. Though aluminium has wide advantages when compared to steel, it stays back in certain properties such as less strength to weight ratio, paint coating etc. Composites have become a better replacement for conventional steel with adequate improvement of mechanical properties and their reduced weight. Though a variety of resins and fibres are available, considering the manufacturing easiness and the mechanical aspects epoxy resin and E- glass fibre is employed in the fabrication work. The term epoxy refers to a chemical group consisting of an

2 oxygen atom bonded to two carbon atoms that are already bonded in some way. The simplest epoxy is a three-member ring structure known by the term alpha-epoxy or 1,2-epoxy. Epoxy resin is almost totally transparent when cured. E- Glass fibre has good tensile and compressive strength and stiffness, good electrical properties. It is relatively low cost, but the impact resistance is relatively poor. E-glass is the most common form of reinforcing fibre used in polymer matrix composites. II. COMPOSITE FAN The use of a ceiling fan will allow you to operate your air conditioner at a higher thermostat setting than usual, since the air movement created by a fan produces a cooling effect on the body. Reduced weight and high strength to weight ratio are the major reasons for the development of composite ceiling fan overthe conventional fan. Though small scale fabrication of composite Fan does not yield a much advantage in manufacturing, but the reduced power consumption and the high strength to weight ratio, provides a conventional manufacturing. The composite blades provide a good reduction in the weight, thereby reducing the power consumption with great stability and stiffness. The combined stiffness and the strength of the fibrous material provide the necessary strength for the composite blades. A. Advantages Over Existing Fan Blade 212 High strength to weight ratio Excellent corrosion resistance No need for painting Good aesthetic appearance Reduced manufacturing cost B. Glass Fibre Reinforced Polymer Fibre reinforced polymers are generally employed to combine the stiffness and strength of the fibrous materials. It has corrosion resistance, low density and mould ability. Today most of the reinforced plastics produced are thermosetting -glass reinforced epoxy or polyester resins. Because of its high strength, easy availability and low cost, generally E-glass fibre is widely employed. FRP composites are lightweight, noncorrosive, exhibit high specific strength, and specific stiffness, are easily constructed, and can be tailored to satisfy performance requirements. For structural applications, FRP composites were typically fabricated using a polymer matrix, such as epoxy, vinyl ester, or polyester, and reinforced with various grades of carbon, glass, and aramid fiber. High strengths can be obtained from fibres with a few microns in diameter, glass fibres provide a relative ease in employing them as reinforcing agents. Composites with a range of strength can be produced according to the glass content and the nature of reinforcement. The lower shrinkage of epoxy resins make them readily suitable than other resins available. III. EXPERIMENTAL STUDY The existing aluminium fan blade is studied to read its various design aspects such as length, thickness, width, aero dynamic design, etc. The difficulties while manufacturing such as the pressure, surroundings is determined by making a few specimens of the blade. Epoxy resin (LY556), hardener (HY951), E-glass fibre Woven roving are used. A. Existing Blade Specifications Manufacturer: Everest Model: HS 1400 Existing blade weight (three blades): 0.48 Kg Material: Aluminium B. Design of Composite Fan Blade The existing design of the aluminium fan blade is taken as the design for the new composite fan blade. Higher-efficiency operation can be achieved for a ceiling fan by making its fan blades aerodynamic, and that such a ceiling fan can further reduce electrical use if it is operated properly in the residence. The aero dynamic design and other design parameters are taken same as the existing one. Figure 1 Design of the Composite Blade

3 C. Design of Composite Fan base The existing design of the aluminium fan base is taken as the design for the new composite fan. Higher-efficiency operation can be achieved for a ceiling fan by making its fan blades aerodynamic, and that such a ceiling fan can further reduce electrical use if it is operated properly in the residence. The aero dynamic design and other design parameters are taken same as the existing one. C. Raw Materials Epoxy resin and E-glass fibre is used. The following table provides the raw materials used in the fabrication process. Hardener is mixed with the resin to provide high viscous solution. The raw materials employed here are mixed in a definite ratio (1:10), considering the design and strength aspects of the composite fan blade. Also releasing agent is applied in the mould to make the mould free from sticking onto the composite layer formed by this process. TABLE I :RAW MATERIALS SI.No. Item Grade 1. EPOXY Resin LY Hardner HY E-glass fiber Woven Roving Releasing agent FIGURE 2 Raw Materials D. Hand Layup Technique Hand lay-up is a simple method for composite production. A mould is used for hand lay-up parts. Existing fan parts is used as the mould. Figure 3 Hand Layup Technique In this process, since curing is done at room temperatures with less pressure, it is easier to fabricate. Before lay-up, the mould is prepared with a release agent to insure that the part will not adhere to the mould. The lay-up technician is responsible for controlling the amount of resin and the quality of saturation [5]. Liquid resin is applied to the mould and then the glass fibre is placed on the top. A roller is used to impregnate the fibre with the resin. Until suitable thickness builds up, more resin and reinforcement layer is applied. It allows the user to optimize the part by placing different types of fabric and mat materials. It is labour intensive but requires only a less capital. E. Fabrication of Composite Fanbase and blade The number layers of fibre required is first determined by finding the thickness of the fibre which is found to be 1mm. Allowances are provided to the mould so that they could be trimmed to the required accurate size. The fibres are cut to the required size. In this technique, first the releasing agent is applied over the mould. The thickness required for the composite blade is built by applying a series of fibre glass layers and liquid resin layers. A roller is used to squeeze the excess resin and create uniform distribution of the resin throughout the fibre surfaces and homogeneous wetting of the fibre is obtained by its squeezing action. The part is then cooled at room temperature over a little pressure. 213

4 IV. EXPERIMENTAL TESTS AND DISCUSSION The main objective of this paper is calculating the power conservation using the composite blade ceiling fan over the existing fans. Also the cost for manufacturing the composite blade, the weight of the fabricated composite blade and the velocity of flow is compared with that of the existing aluminium blade ceiling fan. A. Weight Comparsion The weight of the existing fan and the composite fan were determined using an electronic weighing machine. The weights of the blades were tested individually and the mean values of the three blades are considered for the weight comparison. 1) Aluminium Blade: Weight of aluminium blade (1 unit) = 160 gm Weight of aluminium blades (3 160) = 480 gm 2) Composite blade: Weight of composite blade (1 unit) = 116 gm Total weight of composite blades (3 116) = 348 gm 3)Fan base : Weight of fan base= 340 gm 4)composite base Weight of composite base= 260 gm 3) Percentage saving in weight: Reduction in weight = 220 gm % saving in weight = 27.5 % B. Power Consumption Power consumption being the main objective of this paper, the power consumed by the composite blade ceiling fan is compared with that of the existing aluminium blade fans. The existing blades are fitted with the fan hub and tests are conducted. After the power consumed is noted down, the composite blades are fitted with the fan hub and the tests are conducted, and the power consumed is found out. The calculation is done considering an average run time of 8 hours per day. The cost for running one unit is Rs.7/- (for institutions and industries) 1) Aluminium Fan: Unit consumed for one hour by existing fan = Power consumed for one year = *8 hours*30 days*12 months = 182 Cost for running existing fan at Rs.7 per unit = Rs. 1274/- 2) Composite Fan: Unit consumed for one hour = Power consumed for one year = *8 hours*30 days*12 months = 134 Cost for running at Rs.7 per unit = Rs. 938/- 3) Percentage of power consumed: Cost saved for one year = Rs. 336/- Percentage of power saved = 26 % Figure 4 Weight Comparison From the weight determined in both the cases, it is clear that the replacement of aluminium blade by composite blade has reduced the weight by 132 gm. Thus experimentally, it is clear that the weight gets reduced by 27.5% by replacing the existing aluminium blades with composite blade. Figure 6 Power Consumption The power consumed is saved by 26% by replacing the aluminium blade with composite blade in the ceiling fan. Thus the aim in fabricating the composite blade is stabilized. 214

5 C. Cost Comparsion 1) Composite fan Cost: Cost of composite blade (3 unit) = Rs.330 /- 2) Aluminium blades Cost: Total cost of existing ceiling fan blades = Rs. 410/- 3)base cost: Composite base-rs.420/- Metal base Rs.650/- 3) Percentage saving in cost: Total cost saved = Rs. 310/- % saving in cost = 28 % It is clear that by replacing the aluminium with composite ceiling fan results in a total reduction of 28 % in the cost incurred for the fan. D. Flow Velocity The velocity of the air flow through the ceiling fan employing both the composite blade and the existing aluminium fan is determined using an anemometer. At a pre determined height, the velocity of the flow is determined. Since the air flow rate is a direct measure of the flow velocity, the comparison of the flow velocity is considered to be significant. At 1.65 feet above the ground level, the flow velocity of both the composite and the aluminium blade is determined using anemometer. Flow velocity through Aluminium blade ceiling fan = ft/min Flow velocity through Composite blade ceiling fan = ft/min Difference in flow velocity = ft/min % increase in flow velocity = 15% Figure 7 Difference in Flow Velocity On experimental analysis, it is found that the replacement of the existing aluminium blade with composite ceiling fan blade increases the flow velocity by 15%, which shows that there will be increase in air flow through the fan employing composite blade in place of aluminium blade. E. Total Comparison Table II COMPARISON Description Existing blade Composite blade % reduction Weight 820gm 608gm 27 % Power Consumpti on Cost Blade Flow velocity of % Rs. 1060/- Rs. 750/- 28 % ft/min ft/min 15 % Thus the design and fabrication of the glass fibre reinforced polymer composite ceiling fan is done. Also the composite fan is compared with the existing aluminiumfanand the results are discussed. It is tested that the power consumed by the aluminium blade ( ) is more than that of the composite one ( ). So the usage of the composite fan reduces the power consumption by 26 %. The weight of the existing fan blade is 480 gm, whereas the weight of the composite blade is 348 gm, contributing to a reduction of 27% in weight. The cost of composite ceiling fan blade is Rs.294/- which is 28 % less than the existing aluminium blade ceiling fan. The flow velocity through the composite blade is determined to be 15% more than the flow through the conventional aluminium blade. V. RESULTS Thus, from the study the following results are drawn: i) Usage of glass fibre reinforced polymer ceiling fans reduces the weight of the fan thereby reducing the power consumption by 26% ii) Air flow velocity through the fan increases by 15% by employing glass fibre blades iii) Cost of the ceiling fan reduces by imparting fibre glass polymer in place of existing metal. 215

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