Development of Fast Numerical Method to Solve Nongray Radiative Heat Transfer in Three-dimensional Arbitrary Shaped Systems by Pre-calculating Geometrical Characteristics

通过预先计算几何特性求解三维任意形状系统中非格雷辐射传热的快速数值方法的发展

• 批准号: 09555068
• 负责人: KUDO Kazuhiko
• 金额: $ 3.84万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09555068/
• 关键词: RADIATAIVE HEAT TRANSFER; NUMERICAL ANALYSIS; NONGRAY; FURNACE; BOILER; HEATING FURACE

The objective of this research is to develop a threed-dimensioal nongray radiative-convective heat transfer program for arbitrary shaped systems. For the purpose, new fast algorithm for numerical analysis on nongray radiative heat transfer is developed and confined with a threed-dimensioal nongray radiative-convective heat transfer program for arbitrary shaped systems..In the study, the Monte Carlo method is adopted for the analytical tool for the radiative transfer calculation. As the method is known to be time-consuming, below mentioned unique fast algorithm for numerical analysis on nongray radiative heat transfer is proposed to avoid the repeated use of the method for the times of (number of wave number division)x(number of iterational calculations for temperature convergence).The variables used in the radiative heat transfer analysis are the functions of non-dimensional "optical thichness" which is the product of physical length and absorption coefficient of gas layer. As the valu … More e of the absorption coefficient depends on the temperature and the wave number, the value of the optical depth is not the unique value of the system. Considering that this characteristics of the optical depth is the cause of the necessity of the repeated calculation in nongray analysis, an idea is presented in which optical depth is divided into two parts, physical length between calculational elements and the absorption coefficient. Exploiting that the physical lengths between elements are unique value of the system and do not depend the temperature and wave number the values can be calculated outside the caluculational loop for temperature convergence using the Monte Carlo method. Then, every time when the optical depth is needed in the iteratinal loop, it can easily calculated as the product of the pre-calculated physical lengths and the tentative value of absorption coefficient which depends on the temperature.Owing to the development of the above mentioned method, multiple usage of the time consuming Monte Carlo calculation can be waved, and the total calculating time is reduced to 1/6 for the same accuracy. Less

本研究的目的是为任意形状的系统开发一个三维非灰色辐射对流换热程序。为此，提出了一种新的快速非灰色辐射换热数值分析算法，并结合任意形状系统的三维非灰色辐射-对流换热程序，采用蒙特卡罗方法作为辐射换热计算的分析工具。由于该方法耗时较长，为了避免重复使用该方法的次数（波数划分次数）x（温度收敛的迭代计算次数），本文提出了一种独特的非灰色辐射传热数值分析快速算法。辐射传热分析中使用的变量是无因次“光学厚度”的函数，它是物理长度与气体层吸收系数的乘积。由于吸收系数的值更多地取决于温度和波数，因此光深的值并不是系统的唯一值。考虑到光学深度的这一特性是非灰色分析中必须进行重复计算的原因，提出了将光学深度分为计算单元之间的物理长度和吸收系数两部分的想法。利用元件之间的物理长度是系统的唯一值，不依赖于温度和波数，可以使用蒙特卡罗方法在温度收敛的计算环外计算该值。然后，每次在国际环路中需要光深度时，它可以很容易地计算为预先计算的物理长度与依赖于温度的吸收系数的暂定值的乘积。由于上述方法的发展，可以避免多次使用耗时的蒙特卡罗计算，并且在相同精度下，总计算时间减少到1/6。少

项目成果

Kazuhiko KUDO: "Profiles of Equivalent Gray Absorption Caefficient obtained by Inverse Aualysis in Two-Dimensional Non-Gray Systems" Proc.of 5th ASME/SME Joint Thennal Engng.Conf.掲載決定. (1999)

Kazuhiko KUDO：“通过二维非灰色系统中的逆分析获得的等效灰色吸收系数”，第五届 ASME/SME 联合工程会议 (1999)。

Kazuhiko KUDO,et al.: "Development of Fast Algorithm for Nongray Radiative Heat Transfer Analysis in Systems Surrounded by Gray Walls" Trans.JSME,series B. Vol.63, No, 630 (in Japanese) (in printing). (1999)

Kazuhiko KUDO 等人：“灰墙包围系统中非灰色辐射传热分析的快速算法的开发” Trans.JSME，系列 B. 第 63 卷，第 630 期（日文）（印刷中）。

Kazuhiko KUDO: "Proriles of Eqaivalent Gray Absorption Cotticicut Obtained by Inverse Analysis in Two-Dimensional Non-Gray Gas Systems" Proc.of 5th ASME/JSME Joint Thernal Engry.Conf.(掲載決定). (1999)

Kazuhiko KUDO：“通过二维非灰色气体系统反演获得的等效灰色吸收曲线”Proc. 第五届 ASME/JSME 联合热能会议（1999 年出版）。

Kazuhiko KUDO,et al.: "Inverse Analysis on Two-dimensional Radiative Heat Transfer Systems to Obtain Profeles of Absorption Coefficient" Trans.JSME,series B. Vol.63, No, 615 (in Japanese). 3729-3736 (1997)

Kazuhiko KUDO 等人：“二维辐射传热系统的逆分析以获得吸收系数曲线” Trans.JSME，系列 B. 第 63 卷，第 615 期（日文）。

Kazuhiko KUDO,et al.: "Profiles of Equivalent Gray Absorption Coefficient obtained by Inverse Analysis in Tow-dimensional Non-Gray Systems" Proc.5th ASME/JSME Joint Thermal Engng.Conf.(in printing). (1999)

Kazuhiko KUDO 等人：“通过二维非灰色系统逆分析获得的等效灰色吸收系数的轮廓”Proc.5th ASME/JSME Joint Thermal Engng.Conf.（印刷中）。