INTERNATIONAL JOURNAL OF RESEARCH AND INNOVATION

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1 Subject: Mechanical Engineering IJRIME ANALYSIS OF A BOILER SHELL AT VARIOUS CONDITIONS USING FEA S. Anjani Devi 1, V.V. Kamesh (PhD) 2. 1 Research Scholar, Department of Mechanical Engineering, Aditya Engineering College, Surampalem, Andhra Pradesh, India. 2 Associate Professor, Department of Mechanical Engineering, Aditya Engineering College, Surampalem, Andhra Pradesh, India.. Abstract A boiler or steam generator is a closed component in which fluid is converted into steam by heating under pressure. Thus steam produced from a boiler has many practical applications. The design considerations such as physical size, materials, cost and Thermal specifications of a boiler vary with applications. The aim of this thesis work is to develop optimized boiler to preserve temperature & pressure more efficiently; generally boiler are made with Mild Steel (MS) / Stainless steel with coatings according to the conditions; in this project MS with reaper and dual shell will be analyzed. Coupled field and fatigue analysis will be conducted on plain reaper (empty), & with filler materials to work as insulation layer; in coupled field analysis thermal and structural loads will be analyzed at a time to fine stress, strain, and flux in dual load conditions. Fatigue analysis will be done to determine maximum life/ fatigue behavior. *Corresponding Author: S. Anjani Devi, Research Scholar, Department of Mechanical Engineering, Aditya Engineering College, Surampalem, Andhra Pradesh, India. anjani.sanipina@gmail.com Year of publication: 2017 Paper Type: Review paper Review Type: peer reviewed Volume: IV, Issue: I *Citation: S. Anjani Devi, Research Scholar, Analysis of A Boiler Shell at Various Conditions Using Fea" International Journal of Research and Innovation (IJRI) 4.1 (2017) INTRODUCTION Boiler is one of the most vital devices in a power plant or in industries where a source of stream is required as a source of heat. It is the device/vessel used to create stream by applying heat energy to water and the heat is supplied from the combustion of fuel. Hence brake down of boiler or steam generator at any time may leads to severe damage to the industrial processes. Hence our project reflects the detail procedures to re-establish and start-up a condemned boiler or steam generator such that it fulfil 659

2 the industrial need by maximizing the economy while maintaining fuel economy. A boiler or steam generator is an enclosed container that provides a mean from heat of combustion to be transferred to the working medium (water) until it become heated or convert in steam. The heated steam can be utilized for transferring the heat in several processes that consume the heat of the stream and turns in work or just to heat another substance LITERATURE REVIEW [1] Mr. V. Ashok Kumar and Mr. G. Kumar has worked on Design and Thermal Analysis of Steam Boiler used in Power Plants using CFD analysis and they have given the conclusion on this project as In this thesis the steam flow in steam boiler tubes is modeled using PRO-E design software. The thesis will focus on thermal and CFD analysis with different velocities (25, 30, 35& 40m/s). Thermal analysis done for the steam boiler by steel, stainless steel& brass at different heat transfer coefficient values. These values are taken from CFD analysis at different velocities. By observing the CFD analysis the pressure drop, velocity, heat transfer coefficient, mass flow rate & heat transfer rate increases by increasing the inlet velocities. By observing the thermal analysis, the taken different heat transfer coefficient values are from CFD analysis. Heat flux value is more for brass [2] Mr. S. Krishnanunni and Mr. Josephkunju Paul has done the research work on Evaluation of Heat Losses in Fire Tube Boiler using empirical and experimental methods and they have given the valuable suggestions like The heat losses in dry flue gas and due to unburned fuel are interrelated. So they can be controlled by the same method. Installation of Zirconium oxygen sensor is suggested as the remedy for both the problems. This instrument can reduce the stack loss approximately 3.5% and boiler efficiency can be improved from 80% to 83%. In Power Plants they have worked on geometric modifications on boiler to improve efficiency in this paper they have given the conclusions as In the present project a Modified steam boiler has been designed and optimized for structural and thermal analysis. The Modified steam boiler was studied for3 different cases: Couple field Analysis Modal analysis Harmonic Analysis From the above analysis it is concluded that that the Modified steam boiler has stresses and deflections within the design limits of the material used. The deflections and stresses obtained in the harmonic analysis are also under the design limits. Therefore it is concluded that the Modified steam boiler is safe under the given operating conditions. [4] Mr. D.Madhav and Mr.L.Ramesh done the research work on Heat Recovery through Boiler Blow down Tank they have given suggestions as Blow down water carries thermal energy in the form of steam that can be reused may result in improves the boiler efficiency. Blow down heat recovery system may provide you with significant savings to the boiler plant i.e. from above study reveals total energy saved =625.57KJ/S. [5] Mr. Gireesh Kumar and Mr. Manish Kumar soni has done the research work on Fuel Optimization &increase boiler efficiency by heat extraction system and they have given the suggestions on increased boiler efficiency by optimizing the fuels [6]. Dincer et al. have investigated the Rankine cycle single reheat in sub-critical ranges in terms of the exergy analysis & energy. The system parameters of boiler values were selected in the range between C and C (temperature), and 100 bar and 150 bar (pressure) respectively. [3]SuriBabu, and Mr.Dr.B.Subbaratnam has done the work on Finite Element Analysis of Steam Boiler Used 660

3 PROBLEM DESCRIPTION AND METHODOLOGY PROBLEM DESCRIPTION: Generally maximum researchers are worked on coatings and material suggestions only change of material and coatings become expensive to optimized the boiler or steam generators change of material is very expensive and coatings has to apply frequently. METHODOLOGY: in this work mild steel which is most commonly used and low cost material is used and filler material was used instead of TBC coatings to improve thermal and structural ability s with reduction in cost. Initially literature survey will be done to understand approach to conduct analysis work and data collection will be done to describe about parts, functionality and also to select materials. Model will be prepared to do further analysis work in ansys to evaluate thermal ability s. Geometrical optimization will be implemented in trial and error method through analysis simulations to optimise the boiler to improve efficiency. In the next stage different filler materials will be analysed to suggest best insulation material. Graphs and tables will be prepared for easy understanding; conclusion will be made according to the results. INTRODUCTION TO COMPUTER AIDED DESIGN: It is also known as computer-aided design and drafting (CADD), is the use of computer technology for the process of design and design-documentation. Computer Aided Drafting describes the process of drafting with a computer. These software s made easy to design product in efficient way and also these models can be analyzed to study failure conditions; so that manufacturer can rectify the errors to produce error free products. 661

4 Asbestos Mineral Wool INTRODUCTION TO FEA and ANSYS: Finite element analysis is one of the well-known numerical solution to solve complex problems in efficient way; analytical method doesn t provide solution for all the geometry s and also it doesn t consider different types of boundary and lode conditions also the thickness will be the one of the obstacle for analytical by overcoming above problems numerical methods are designed. There are different types of numerical methods: Finite element method: for structural, vibration, thermal, fluid flow, electrical, electronics, magnetic and couple field ( combination of multi disciplines) Boundary element method: for echostics. Discreet element method:for rock solid models and for kinematics. Mesh less method: for injection and cast molding process. COUPLED ANALYSIS OF BOILER OR STEAM GENERATOR: WORK AND RESULTS Material properties: Mild steel: 662

5 COUPLED ANALYSIS OF BOILER OR STEAM GENERATOR with Reapers 663

6 COUPLED ANALYSIS OF BOILER OR STEAM GENERATOR with step Reaper COUPLED ANALYSIS OF BOILER OR STEAM GENERATOR WITH STEP REAPER AND FILLER MATERIAL MINERAL WOOL 664

7 COUPLED ANALYSIS OF BOILER OR STEAM GENERATOR WITH STEP REAPER AND FILLER MATERIAL ASBESTOS RESULT TABLES AND GRAPHS Step Parameter Plain Reaper Reaper Temperature oc Total heat flux w/mm Directional heat flux x Directional heat flux y Directional heat flux z Thermal error e e6 Parameter Plain Reaper Step Reaper Total deformation mm stress Mpa elastic strain Parameter Plain Reaper Step Reaper Life-- MIN/MAX 31475/1e /1e /1e6 Safety factor alternating stress

8 STEP REAPER AND FILLER MATERIAL MINERAL Parameter WOOL ASBESTOS Temperature o c Total heat flux w/mm Directional heat flux x Directional heat flux y Directional heat flux z Thermal error e e8 GRAPHS Coupled analysis Parameter MINERAL WOOL ASBESTOS Total deformation mm stress Mpa elastic strain Parameter MINERAL WOOL ASBESTOS Life-- MIN/MAX e5/1e /1e6 Safety factor alternating stress Mpa

9 STRUCTURAL ANALYSIS Fatigue analysis 667

10 CONCLUSION STEP REAPER AND FILLER MATERIAL THERMAL ANALYSIS This thesis work is done on boiler or steam generator to optimize the efficiency; geometrically modified to add a layer of Thermal insulation /barrier material to pressure the temperature inside the boiler or steam generator shell. In first stage literature and data collection was done on boiler or steam generators and barrier material s to understand design and analysis methodology. A 3D model was prepared using the rough dimension s from previous research paper to do further study model was converted into FEM model. Couple field and fatigue analysis was conducted on boiler or steam generator for basic generic model to find structural and thermal behavior while applying both load condition s at a time. In next step geometrical modifications are done after observing previous analysis study results to add barrier filling area; New model was analyzed with empty filler with two variations in medal to evaluate new models; as per the analysis results reapers with multi segments will be the best choice. Multi segment model was analyzed with filler material s asbestos and mineral wool; as per the analysis result s mineral wool will be the best choice for thermal barrier 668

11 layer to preserve temperature inside boiler or steam generator shell. [10] Referred Steam generators and waste heat boilers for process and plant engineers by V.Ganapathy. References: [1] Design and Thermal Analysis of Steam Boiler used in Power Plants V. Ashok Kumar, G. Kumar, K.Pavan Kumar IARJSET ISSN (Online) ISSN (Print) 2394-Vol. 3, Issue 11, November 2016 AUTHORS [2] International Journal of Emerging Technology and Advanced Engineering (ISSN , ISO 9001:2008 Certified Journal, Volume 2, Issue 12, December 2012) 301 Evaluation of Heat Losses in Fire Tube Boiler S.Krishnanunni1, Josephkunju Paul C, Mathu Potti, Ernest Markose Mathew [3] Referred Finite Element Method and Applications in Engineering Using Ansys second edition by Springer. S. Anjani Devi, Research Scholar, Department of Mechanical Engineering, Aditya Engineering College, Surampalem, Andhra Pradesh, India. [4] Referred High pressure boilers fifth edition by Frederick M Steingress, Harold j Frost, Daryl R Walker. [5] SSRG International Journal of Mechanical Engineering (SSRG-IJME) volume 1 Issue 6 October 2014 ISSN: , Page 28 Finite Element Analysis of Steam Boiler Used In Power Plants M. SuriBabu, Dr. B. Subbaratnam V.V. Kamesh (PhD), Associate Professor, Department of Mechanical Engineering, Aditya Engineering College, Surampalem, Andhra Pradesh, India. [6] International Journal of Engineering Trends and Technology (IJETT) - Volume4Issue5- May 2013 ISSN: ,Page 1597,Heat Recovery through Boiler Blow down Tank D.Madhav, L.Ramesh, M.Naveen [7] IJITE Vol.03 Issue-06, (June, 2015) ISSN: International Journal in IT and Engineering, Impact Factor , Page 127 A Journal paper on Fuel Optimization &increase boiler efficiency by heat extraction system Gireesh Kumar,Manish Kumar soni Post Graduate Student Jagannath University, Jaipur,Rajasthan, INDIA DR. M.P.Singh 3 Professor, Jagannath University, Jaipur, Rajasthan, INDIA. [8] Referred Boiler plant and Distribution system Optimization manual third edition by Harry Taplin, P.E [9] Referred Finite Element Modeling and Simulation with Ansys Workbench by xiaolin Chen, Yijun Liu. 669