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Spray Cooling Trajectory Angle Impact Upon Heat Flux Using a Straight Finned Enhanced SurfaceExperiments were conducted to study the effects of spray trajectory angles upon heat flux for flat and enhanced surface spray cooling. The surface enhancement consisted of straight fins machined on the top surface of a copper heater block. Spray cooling curves were obtained with the straight fin surface aligned both parallel (axial) and perpendicular (transverse) to the spray axis. Measurements were also obtained on a flat surface heater block for comparison purposes. Each copper block had a cross-sectional area of 2.0 sq cm. A 2x2 nozzle array was used with PF-5060 as the working fluid. Thermal performance data was obtained under nominally degassed (chamber pressure of 41.4 kPa) conditions. Results show that the maximum CHF in all cases was attained for a trajectory angle of 30' from the surface normal. Furthermore, trajectory angles applied to straight finned surfaces can have a critical heat flux (CHF) enhancement as much as 75% (heat flux value of 140 W/sq cm) relative to the vertical spray orientation for the analogous flat surface case under nominally degassed conditions.
Document ID
20050210107
Acquisition Source
Goddard Space Flight Center
Document Type
Preprint (Draft being sent to journal)
Authors
Silk, Eric A.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Kim, Jungho
(Maryland Univ. College Park, MD, United States)
Kiger, Ken
(Maryland Univ. College Park, MD, United States)
Date Acquired
September 7, 2013
Publication Date
January 1, 2005
Subject Category
Mechanical Engineering
Report/Patent Number
HT2005-72634
Meeting Information
Meeting: ASME 2005 Heat Transfer Summer Conference
Location: San Francisco, CA
Country: United States
Start Date: July 17, 2005
End Date: July 22, 2005
Sponsors: American Society of Mechanical Engineers
Funding Number(s)
CONTRACT_GRANT: N00014-04-10315
Distribution Limits
Public
Copyright
Public Use Permitted.
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