Doctoral Dissertations


"The results of a parametric study conducted to examine heat transfer behavior inside the annular space of a shrouded motor are reported. The main goal is to examine the validity of the 1 ft/s rule of thumb used by industry, for the case of viscous oil (100 cp @ 50°C). The study was conducted using the computational fluid dynamics software CFX4.2 to simulate fluid flow and heat transfer through the annular configuration. The geometry modeled consisted of an outer cylinder or casing, with the shrouded motor located inside. The flow of viscous oil was simulated by using SAE50 motor oil properties. A range of fluid inlet velocities in combination with different shroud sizes was used in the study. A constant heat flux from the motor wall was assumed. Fluid flow through the outer annulus (casing/shroud) was considered isothermal; while inside the inner annulus a boundary condition of the second kind (heated inner wall, insulated outer wall) is applied. The model includes a Power Law viscosity model. Default differencing schemes, under-relaxation factors and number of sweeps have been modified in order to allow the program to work with a wider range of Reynolds numbers without introducing significant errors. This in combination with the proper design of the grid assures the convergence of the solutions.

A method for the design of the shroud has been developed using a response surface methodology approach. Using this method, the minimum fluid velocity required to achieve the proper cooling effect when using SAE50 motor oil has been found to be around 0.8 m/s (2.6 ft/s) inside the heated annulus.

Additionally, the introduction of openings on the shroud has been investigated as a method to increase the cooling effect of the fluid. Preliminary results show that the incoming fluid from the openings pushes the axial fluid flow pattern towards the motor wall causing the additional cooling of the motor wall. The results of using three openings show that reductions of motor wall temperature ranging from 11 to 18% at the end of the heated section can be obtained. Overall pressure drop and thermal behavior in the system are consistent with the cases in the literature"--Abstract, page iii.


Dunn-Norman, Shari
Finaish, Fathi

Committee Member(s)

Numbere, Daopu Thompson, 1951-
Koederitz, Leonard
Cawlfield, Jeffrey D.


Geosciences and Geological and Petroleum Engineering

Degree Name

Ph. D. in Petroleum Engineering


University of Missouri--Rolla

Publication Date

Fall 2000


xv, 122 pages

Note about bibliography

Includes bibliographical references (pages 118-121).


© 2000 Jesus Ramon Rodriguez Leon, All rights reserved.

Document Type

Dissertation - Restricted Access

File Type




Thesis Number

T 7857

Print OCLC #


Link to Catalog Record

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