Numerical Simulation And Structure Optimization Of Gas Turbine Combustor Transition Section

With the constant improvement of productivity level and rapid growth of economy inthe modern society, the demand for energy is rapidly increasing. The development pace of acountry is closely related to the use of energy. Gas turbine technology, a high-techintegration of multiple techniques which has been related to the livelihood project such asenergy, transportations and national defense, plays a very important role in national industryand in the great manufacturing industry. Empirical design method, based on lots of data andresults of practical experience, requires numerous tests. Therefore, it is very difficult to getoverall and accurate data. In recent years, owing to the rapid development of computationalfluid dynamics, computational combustion kinetics and computer technology, numericalsimulation method has been widely applied. Not only is the cost of design and research isreduced, but also time is saved. What’s more, with this method, the result obtained is moreaccurate and overall than that obtained by using empirical design method.This dissertation focuses on a country’s sub-project the optimization of transitionalsection of combustion chamber. Under the condition of guaranteeing the vibrationcharacteristics of transition section of gas turbine combustor, the paper aims to optimize thetransitional section. The paper mainly expounds the optimization of transitional sectionfrom these two aspects:1) analyzing the coupling of flow field and thermal field intransitional section from the aspect of fluid dynamics, we can obtain the rationaldistribution of cooling hole;2) researching on modal analysis while ensuring itsfundamental frequency and using size optimization, we can obtain the minimum wallthickness. The research contents are as follows:1) Building the physical and mathematical models of transition section of combustionchamber. The physical model is standard model while the discrete mathematicmodel is SIMPLE algorithms.2) According to the published data, founding the geometric model by applying surfacefitting function of CATIA software. Applying ICEM software, geometry clean and meshgeneration are used in simplified model of the geometric model. In addition, couplinganalysis of flow field and temperature field as well as multi-field is carried out by usingSIMPLE iterative algorithm of FLUENT software.3) Analyzing the coupling of flow field and thermal field in transitional section whilecombining fluid dynamics to get other two optimization schemes which can meet the design requirements.4) Applying geometry clean and mesh generation on simplified model of transitionalsection by using Hypermesh software, we then build finite element model and do researchon modal analysis with Lnaczos method of Optistruct software. Furthermore, sizesoptimization is used to analyze the wall thickness of draft-tube by using Optistruct softwareagain then we get the reasonable wall thickness value of three drilling schemes with whichwe get the optimization schemes of transitional section..