Date of Award
Summer 2007
Document Type
Dissertation - Restricted
Degree Name
Doctor of Philosophy (PhD)
Department
Mechanical Engineering
First Advisor
Park, Hyunjae
Second Advisor
Borg, John
Third Advisor
Cariapa, Vikram
Abstract
In this dissertation, laminar fluid flow and heat transfer characteristics in coiled tube systems are numerically investigated using a commercially available CFD package (Fluent) and analytically investigated using dimensional analysis and order-of-magnitude analysis. As part of the investigation, a general coiled tube coordinate system has been developed and incorporated into the dimensional and dimensionless governing equations for use in the order-of-magnitude analysis. The CFD modeling constitutes the bulk of the investigation. Laminar flow and uniform wall temperature heat transfer conditions in toroidal, helicoidal and spiral coiled tube systems are modeled. Developing-flow velocity and temperature fields are presented and discussed. Where applicable, appropriate correlations for predicting the developing and developed flow and heat transfer performance in the modeled coiled tube systems are developed and discussed. As part of the order-of-magnitude analysis, significant/ dominant terms in the momentum and energy equations are identified in terms of dimensionless flow and geometric parameters ( e.g., Reynolds number, Dean number, Prandtl number, curvature ratio, etc.). At locations along the coiled tube flow path where balance occurs between the inertial and viscous forces or between the viscous and centrifugal forces, the order-of-magnitude analysis provides quantitative insight into behaviors observed in analysis of the CFD results. The analytical research serves as a bridge between the numerical modeling and future experimental research and design.