The paper presents three power-type correlations of a simple form, which are valid for Reynolds numbers range from 3.10^3 ≤ Re ≤ 10^6, and for three different ranges of Prandtl number： 0.1 ≤ Pr ≤ 1.0, 1.0≤ Pr ≤...The paper presents three power-type correlations of a simple form, which are valid for Reynolds numbers range from 3.10^3 ≤ Re ≤ 10^6, and for three different ranges of Prandtl number： 0.1 ≤ Pr ≤ 1.0, 1.0≤ Pr ≤ 3.0, and 3.0 ≤Pr ≤ 10^3. Heat transfer correlations developed in the paper were compared with experimental results available in the literature. The comparisons performed in the paper confLrm the good accuracy of the proposed correlations. They are also much simpler compared with the relationship of Gnielinski, which is also widely used in the heat transfer calculations.展开更多
This paper presents non-linear and linear models of flow system of laboratory stand (semi-industrial scale) with pressurized fluidized bed boiler. The non-linear model belongs to the class of lumped parameter models. ...This paper presents non-linear and linear models of flow system of laboratory stand (semi-industrial scale) with pressurized fluidized bed boiler. The non-linear model belongs to the class of lumped parameter models. The linear model was obtained experimentally using a novel method for design of control systems in industrial plants - MIKOZ. This study has connection with comparison of various methods of mathematical modeling of flow systems frequently encountered in power equipment.展开更多
The purpose of this paper is to present method of the numerical modeling of the hybrid rocket engine's work as a tool for designing engines of this type.The model is intended as an accurate and simple to use devel...The purpose of this paper is to present method of the numerical modeling of the hybrid rocket engine's work as a tool for designing engines of this type.The model is intended as an accurate and simple to use development tool for use in preliminary design stages of hybrid rocket engines,improving the effectiveness and quality of this process.General assumptions underlying the use of a model are presented,together with an analysis of past work in this field.Results of an extensive experimental campaign are presented and compared with the results of numerical modelling in order to calibrate the proposed model and evaluate its accuracy.Parameter variation and optimization were conducted,proving functionality of the methodology.Presented numerical calculations show that the adopted approach to reduce the analysis time and complexity was correct.This method of numerical calculation of hybrid engine working parameters combines aspects of accuracy and simplicity at the early design stage to avoid timeconsuming and costly changes in subsequent detailed stages of design.展开更多
文摘The paper presents three power-type correlations of a simple form, which are valid for Reynolds numbers range from 3.10^3 ≤ Re ≤ 10^6, and for three different ranges of Prandtl number： 0.1 ≤ Pr ≤ 1.0, 1.0≤ Pr ≤ 3.0, and 3.0 ≤Pr ≤ 10^3. Heat transfer correlations developed in the paper were compared with experimental results available in the literature. The comparisons performed in the paper confLrm the good accuracy of the proposed correlations. They are also much simpler compared with the relationship of Gnielinski, which is also widely used in the heat transfer calculations.
文摘This paper presents non-linear and linear models of flow system of laboratory stand (semi-industrial scale) with pressurized fluidized bed boiler. The non-linear model belongs to the class of lumped parameter models. The linear model was obtained experimentally using a novel method for design of control systems in industrial plants - MIKOZ. This study has connection with comparison of various methods of mathematical modeling of flow systems frequently encountered in power equipment.
文摘The purpose of this paper is to present method of the numerical modeling of the hybrid rocket engine's work as a tool for designing engines of this type.The model is intended as an accurate and simple to use development tool for use in preliminary design stages of hybrid rocket engines,improving the effectiveness and quality of this process.General assumptions underlying the use of a model are presented,together with an analysis of past work in this field.Results of an extensive experimental campaign are presented and compared with the results of numerical modelling in order to calibrate the proposed model and evaluate its accuracy.Parameter variation and optimization were conducted,proving functionality of the methodology.Presented numerical calculations show that the adopted approach to reduce the analysis time and complexity was correct.This method of numerical calculation of hybrid engine working parameters combines aspects of accuracy and simplicity at the early design stage to avoid timeconsuming and costly changes in subsequent detailed stages of design.
