Abstract
ABSTRACT Water-pumping windmills are reliable alternatives to provide water in some areas isolated from the electricity network, especially those with poor wind sources that are insufficient to operate wind turbines to generate electricity. The successful design of windmills for water pumping requires careful study of many variable parameters depending on the wind pattern and topography of the site. However, in this study, the researcher applied the Reverse Engineering (RE) approach, and some activities are usually used as a prerequisite when designing windmills. These activities cannot be neglected when applying RE for successfully manufacturing the windmills for obtaining 3D CAD models of the windmill rotor. The 3D models were the basis for manufacturing the windmill Rotor prototype installed at a pilot site in a suburb of the city of Tajoura. The wind data recorded at the Libyan Center of Solar Energy Research and Studies (CSERS) for several years were used to calculate daily and monthly average wind speed and study the daily wind pattern. The analysis of the collected wind data showed that the minimum and maximum daily average wind speed at Tajoura varies from 2.35m/s to 4.69m/s, and the annual average wind speed is 3.24m/s. Among the design, activities are estimating the wind resources available at the site to size the system to provide the site water requirements of 5 m³/day. From this point on, a commercial water-pumping windmill of 4.88m (16ft) and a standard tower height of 12m was chosen to target a RE application to obtain a CAD model. RE is accomplished in three phases: digitizing the component (part), processing the measured data, and creating the CAD model. To adopt the 3D model for all parts, they must be compared with the original scanned data using Deviation Analysis in CATIA. After adopting the 3D models of all the Rotor components, the 3D assembly models were created based on the RE approach. As for the curving Sails, the researcher applied the reverse engineering approach to design a bending die for curving water pumping windmill Sails, using simulation programming Computerized numerical control (CNC) machines utilizing computer-aided design and computer-aided manufacturing (CAD/CAM) systems and CNC machining technology to manufacture the die. The Computer-Aided Three-Dimensional Interactive Application (CATIA) V5 was used as an integrated CAD/CAM system for designing and developing the die and simulating the operation through graphic models in 3D. Due to the difficulty of manually manufacturing the curving of the Sails based on the available labor, the number of Sails used to produce one unit of the water pumping windmill, and the importance of the Sails in improving the efficiency of the windmill system, the researcher’s decision was made to design and manufacture a single-operation die. This die consists of four parts to suit the available CNC machine capacity for curving the Sails using the Sail's 3D model of the RE. A CAM model was prepared to machine the die parts, a tool path simulation was performed using CATIA V5, and all machining operations were programmed. Using a CNC machine center, all the die parts were machined, assembled using welding, and the Sails prototypes were manufactured. Finally, it is worth noting that the windmills for water pumping could not be manufactured solely by just applying reverse engineering.