국내 최대 기계 및 로봇 연구정보

기술보고서

기술보고서 게시판 내용
타이틀	A Critical Analysis of the Accuracy of Several Numerical Techniques for Combustion Kinetic Rate Equations
저자	Krishnan Radhakrishnan
Keyword	Stiffness; Reaction kinetics; Combustion chemistry; Numerical method; Accuracy; Efficiency
URL	http://gltrs.grc.nasa.gov/reports/1993/TP-3315.pdf
보고서번호	NASA TP-3315
발행년도	1993
출처	NASA Glenn Research Center
ABSTRACT	A detailed analysis of the accuracy of several techniques recently developed for integrating stiff ordinary differential equations is presented. The techniques include two generalpurpose codes EPISODE and LSODE developed for an arbitrary system of ordinary differential equations, and three specialized codes CHEMEQ, CREK1D and GCKP84 developed specifically to solve chemical kinetic rate equations. The accuracy study is made by application of these codes to two practical combustion kinetics problems. Both problems describe adiabatic, homogeneous, gasphase chemical reactions at constant pressure, and include all three combustion regimes: induction, heat release and equilibration. To illustrate the error variation in the different combustion regimes the species are divided into three types, reactants, intermediates and products, and error versus time plots are presented for each species type and the temperature. These plots show that CHEMEQ is the most accurate code during induction and early beat release. During late heat release and equilibration, however, the other codes are more accurate. A single global quantity, a mean integrated rootmeansquare error, that measures the average error incurred in solving the complete problem is used to compare the accuracy of the codes. Among the codes examined, LSODE is the most accurate for solving chemical kinetics problems. It is also the most efficient code, in the sense that it requires the least computational work to attain a specified accuracy level. An important finding is that use of the algebraic enthalpy conservation equation to compute the temperature can be more accurate and efficient than integrating the temperature differential equation.