文档介绍：A STUDY OF HEAT PUMP FIN STAGED EVAPORATORS
UNDER FROSTING CONDITIONS
A Dissertation
by
JIANXIN YANG
Submitted to the Office of Graduate Studies of
Texas A&M University
in partial fulfillment of the requirements for the degree of
DOCTOR OF PHILOSOPHY
May 2003
Major Subject: Mechanical Engineering
A STUDY OF HEAT PUMP FIN STAGED EVAPORATORS
UNDER FROSTING CONDITIONS
A Dissertation
by
JIANXIN YANG
Submitted to Texas A&M University
in partial fulfillment of the requirements
for the degree of
DOCTOR OF PHILOSOPHY
Approved as to style and content by:
___________________________
Dennis L. O’Neal
(Chair mittee)
___________________________ ____________________________
Nagamangala K. Anand Kalyan Annamalai
(Member) (Member)
___________________________ ____________________________
Mark T. Holtzapple John A. Weese
(Member) (Head of Department)
May 2003
Major Subject: Mechanical Engineering
iii
ABSTRACT
A Study of Heat Pump Fin Staged Evaporators
Under Frosting Conditions. (May 2003)
Jianxin Yang, ., Jiaotong University, Xi’an, China
., Jiaotong University, Xi’an, China
Chair of mittee: Dr. Dennis L. O’Neal
This dissertation provides a detailed description of the research pleted on fin staged heat
exchangers. The effects of staging fin on the frosting performance of heat pump evaporators and the
whole heat pump system have been studied experimentally and theoretically.
Frost degrades the performance of fin-and-tube outdoor coils as well as the whole heat pump
system. The objective of the experimental part of this study was to investigate the effects of the staging
fin on the frost/defrost performance of heat pump outdoor coils under different operating conditions. To
plish this objective, a series of frosting tests was conducted on an off-the-shelf heat pump system
with five (three two-row and two three-row) evaporators over a range of outdoor temperatures and
humidities and a range of airflo