Direct Computational Simulations for Internal Condensing Flows and Results on Attainability/Stability of Steady Solutions, Their Intrinsic Waviness, and Their Noise Sensitivity

Forced Flow of Vapor Condensing Over a Horizontal Plate (Problem of Cess and Koh)* - Steady and Unsteady Solutions of the Full 2-D Problem

Accurate steady and unsteady numerical solutions of the full 2-D governing equations – that model the forced film condensation flow of saturated vapor over a semi-infinite horizontal plate (the problem of Cess [1] and Koh [2]) are obtained over a range of flow parameters. The results presented here are used to better understand the limitations of the well-known similarity solutions given by Koh...

Computational study of internal and external condensing flows and experimental synthesis to investigate their attainability and stability in ground-based and space-based environments

Effects of Gravity, Shear and Surface Tension in Internal Condensing Flows: Results From Direct Computational Simulations

The paper presents accurate numerical solutions of the full two-dimensional governing equations for steady and unsteady laminar/laminar internal condensing flows. The results relate to issues of better design and integration of condenser-sections in thermal management systems (looped heat pipes, etc.). The flow geometry, in normal or zero gravity, is chosen to be the inside of a channel with fi...

A Quasi One-dimensional Method and Results for Steady Annular/stratified Shear and Gravity Driven Condensing Flows

This paper presents an effective quasi one-dimensional (1-D) computational simulation methodology and some important results for steady annular/stratified (or film wise) internal condensing flows of pure vapor. Though the approach is strictly valid for smooth, laminar vapor/laminar condensate flows, it is also approximately valid for laminar condensate and turbulent vapor which are laminar in t...

An investigation on the effects of camshaft surface defects on producing high-frequency noises in internal combustion engines

Valvetrain is one of the major sources of noise and vibration in IC engines. The importance of cam surface quality parameters is highlighted in the valve train mechanisms with direct sliding contact between cam and tappet. In this paper, the influence of surface quality parameters on high frequency noise producing is investigated. The roughness and waviness of some intake and exhaust camshafts ...