IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 _______________________________________________________________________________________________ Volume: 03 Issue: 05 | May-2014, Available @ http://www.ijret.org 491 DOOR OPENING ANALYSIS OF WIND TURBINE STEEL TUBULAR TOWER Ajay R. Vaghela 1 , G.S.Doiphode 2 1 ME Student, Applied Mechanics Department, Faculty of Technology and Engineering, Gujarat, India 2 Assistant Professor, Applied Mechanics Department, Faculty of Technology and Engineering, Gujarat, India Abstract The main objective is to investigate the stresses around the door opening for the load cases that creates highest stresses. The influence of different material thicknesses at the tower lower parts. It investigates the lower tower section which includes the door opening which is used for service and maintenance inside the tower. The loading of the tower generates the stresses around the door opening and these stresses will analyze for static analysis using the FEM software ANSYS 14.5. As there is more probability of having crack near the door opening. To investigate the influence on the stress level and ultimate load of the tower, the tower shell thickness around the door opening varied in simulation .There are total six models prepared in the paper among which two models are prepared with uniform thickness of 38 mm, two models are prepared with 38 mm thickness at the base and 15 mm at the top and two models are prepared with 70 mm thickness at the base and 15 mm at the top. For every condition there are two wind cases considered in first direction of wind is considered on the side of door opening and in second case wind direction is considered on the opposite side of the door opening. After got the values for the stresses fracture analysis and fatigue analysis of the section near the door opening have carried out. We uses steel of grade 355 (S355) and wind data has calculated according to the IS 875 part 3. Keywords: door opening, ANSYS, Shell thickness, and Wind turbine tower ----------------------------------------------------------------------***-------------------------------------------------------------------- 1. INTRODUCTION In 2012, despite a slowing global economy, India’s electricity demand continued to rise. Electricity shortages are common, and over 40% of the population has no access to modern energy services. India’s electricity demand is projected to more than triple between 2005 and 2030. In the recently released National electricity Plan (2012) the Central electricity Authority projected the need for 350-360 GW of total generation capacity by 2022. Despite major capacity additions over recent decades, power supply struggles to keep up with demand [1]. Fig -1: Wind turbine in India [1] India had another record year of new wind energy installations between January and December 2011, installing more than 3 GW of new capacity for the first time to reach a total of 16,084 MW. As of march 2012, renewable energy accounted for 12.2 percent of total installed capacity, up from 2 percent in 1995. Wind power accounts for about 70 percent of this installed capacity. By the end of August 2012, wind power installations in India had reached 17.9 GW. Under the New Policies Scenario of the World energy outlook (2011), total power capacity in India would reach 779 GW in 2035. To reach 779 GW in 2035, without a significant role for renewables. During fiscal year 2011- 2012 wind energy alone delivered over 3GW to India’s new installed capacity, accounting for over 16.5 percent of total new installed capacity. 1.1 Preliminary Remarks To extract energy from wind, Wind turbines emerged as one of the most efficient ways of converting the kinetic energy in wind into mechanical power. Many energy providers invested in research and development of wind turbines. Now a days wind turbines are installed in many countries. Steel towers for multi megawatt turbine consist usually of several conical steel segments which are welded together to sections. These sections are connected by bolted flange connection. A typical feature of these towers is the presence of a manhole cut-out near the bottom, serving purposes of accessibility into the tower for maintenance of the electrical and mechanical equipment. As stated in Part 1–6 of EN1993, a hole in a shell of revolution (Cylindrical or conical) with radius r and thickness t may be neglected in the modelling provided that