Transient Heat Transfer of Piston/Rings/Liner System in Diesel Engines

2005 ◽  
Author(s):  
Daxi Xiong ◽  
Tian Tian ◽  
Victor Wong
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Transfer Process ◽  
Diesel Engines ◽  
Frictional Heating ◽  
Heat Transfer Process ◽  
Transient Heat Transfer ◽  
Transient Temperature ◽  
Piston Rings ◽  
Liner System

In diesel engines, transient heat transfer in the piston/rings/liner system greatly affects the performance of the engine, such as in carbon deposit buildup, microwelding, lubricant degradation, and changing mechanical properties of the materials. The current work aims at studying the local piston/rings/liner transient heat-transfer process by incorporating real time dynamics of the rings in sufficient detail. In the present study, several techniques have been adopted to simulate the transient heat transfer process, with fully-incorporated ring dynamics. These techniques include using the model/submodel approach, local refined mesh approach, and the virtual thermal conductivity approach. The transient temperature and heat flux profiles in the piston and rings are illustrated. The results show that the relative movement of the rings greatly affects the temperature/heat flux distribution and the peak temperature in the top ring. The friction heating between the top ring and the liner is also evaluated. The analysis demonstrates that under some extreme conditions when frictional heating reaches its peak value, some heat flux directs back to enter the ring.

Improvement of Transient Heat Transfer Models for the Coupled 3-D Moving Piston Assembly-Liner System

2007 ◽  
Author(s):  
Yankun Jiang ◽  
Zhien Liu ◽  
Rolf D. Reitz ◽  
Zheling Dong ◽  
Xiaoming Ye
Keyword(s):  
Heat Transfer ◽  
Gasoline Engine ◽  
Sparse Matrix ◽  
Cylinder Liner ◽  
Heat Transfer Model ◽  
Transient Heat Transfer ◽  
Transfer Model ◽  
Piston Rings ◽  
Liner System ◽  
Piston Assembly

A transient heat transfer model for the coupling 3-D moving piston assembly-liner system has been successfully improved for predicting temperature distributions in the components of internal combustion engine chamber. In the model the effect of the 3-D friction heat generated at the piston ring/cylinder liner interfaces and the multi-dimensional lubricant film thickness between the piston rings and the liner has been taken into account. A directly coupled finite element method (FEM) is employed in the model for establishing the heat transfer relation among the moving piston assembly-cylinder liner components. A 3-D discrete model of the coupling system is formulated, which includes the piston rings, piston, liner and cylinder. Due to the complexity of the temperature stiffness matrix, a sparse matrix data structure is employed in the model to save the memory and calculation time. Finally, the 3-D coupling heat transfer model has been used to analyze heat transfer processes in a gasoline engine.

scholarly journals Modelling heat transfer in heterogeneous media using fractional calculus

2013 ◽  
Vol 371 (1990) ◽  
pp. 20120146 ◽  
Author(s):  
Dominik Sierociuk ◽  
Andrzej Dzieliński ◽  
Grzegorz Sarwas ◽  
Ivo Petras ◽  
Igor Podlubny ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Differential Equation ◽  
Partial Differential Equation ◽  
Heat Flux ◽  
Transfer Function ◽  
Transfer Process ◽  
Heterogeneous Media ◽  
Heat Transfer Process ◽  
Order Partial Differential Equation ◽  
Partial Differential

This paper presents the results of modelling the heat transfer process in heterogeneous media with the assumption that part of the heat flux is dispersed in the air around the beam. The heat transfer process in a solid material (beam) can be described by an integer order partial differential equation. However, in heterogeneous media, it can be described by a sub- or hyperdiffusion equation which results in a fractional order partial differential equation. Taking into consideration that part of the heat flux is dispersed into the neighbouring environment we additionally modify the main relation between heat flux and the temperature, and we obtain in this case the heat transfer equation in a new form. This leads to the transfer function that describes the dependency between the heat flux at the beginning of the beam and the temperature at a given distance. This article also presents the experimental results of modelling real plant in the frequency domain based on the obtained transfer function.

Modeling Heat Transfer in Heterogeneous Media Using Fractional Calculus

2011 ◽  
Author(s):  
Dominik Sierociuk ◽  
Andrzej Dzielin´ski ◽  
Grzegorz Sarwas ◽  
Ivo Petras ◽  
Igor Podlubny ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Differential Equation ◽  
Partial Differential Equation ◽  
Heat Flux ◽  
Transfer Function ◽  
Transfer Process ◽  
Heterogeneous Media ◽  
Heat Transfer Process ◽  
Order Partial Differential Equation ◽  
Partial Differential

The paper presents the results of modeling the heat transfer process in heterogeneous media with the assumption that part of the heat flux is dispersed in the air around the beam. The heat transfer process in solid material (beam) can be described by integer order partial differential equation. However, in heterogeneous media it can be described by sub- or hyperdiffusion equation which results in fractional order partial differential equation. Taking into consideration that the part of the heat flux is dispersed into the neighbouring environment we additionally modify the main relation between heat flux and the temperature, and we obtain in this case the heat transfer equation in the new form. This leads to the transfer function which describes the dependency between the heat flux at the beginning of the beam and the temperature at the given distance. The article also presents the experimental results of modeling real plant in the frequency domain basing on the obtained transfer function.

Heat Transfer Aspects of Nonisothermal Axisymmetric Upset Forging

1984 ◽  
Vol 106 (3) ◽  
pp. 187-195 ◽  
Author(s):  
P. Dadras ◽  
W. R. Wells
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Finite Difference ◽  
Transfer Process ◽  
Heat Transfer Process ◽  
Physical Characteristics ◽  
Transient Heat Transfer ◽  
Interfacial Film ◽  
Upset Forging ◽  
Finite Difference Solution

A finite difference solution for the transient heat transfer during axisymmetric upset forging has been developed. The interfacial film between the die and the billet has been included in the analysis, and all modes of heat transfer have been taken into account. The results of a parallel experimental study have also been presented. The effects of geometrical and physical characteristics of the billet and the die on the heat transfer process, particularly on die heating, have been systematically investigated.

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