Analysis and Verification of the Icing Scaling Equations. Volume 1. Revision

• Main Author: Ruff, Gary A
• Other Authors: ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AFB TN
• Format: Text
• Language: English
• Published: 1986
• Subjects: Snow; Ice and Permafrost; *ICE FORMATION; *SCALING FACTOR; AERODYNAMICS; COMPUTER PROGRAMS; DROPS; DYNAMIC PRESSURE; EQUATIONS; FLOW FIELDS; ICE; IMPINGEMENT; LIMITATIONS; MACH NUMBER; MATHEMATICAL MODELS; METEOROLOGY; MODEL TESTS; MODEL THEORY; MODELS; PARAMETERS; REYNOLDS NUMBER; SHAPE; THERMAL PROPERTIES; THERMODYNAMICS; VELOCITY; SIMICE COMPUTER PROGRAM; METEOROLOGICAL PARAMETERS; ICE SHEDDING; LPN-AEDC-D188EW; PE65807F; Ice; permafrost
• Online Access: http://www.dtic.mil/docs/citations/ADA167976; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA167976

Study objectives were to evaluate the equations governing the ice- accretion process to identify proposed scaling parameters and to conduct tests to determine which, is any, of the proposed methods produced scale ice accretions. Study results include: (1) A set of equations that can be used to calculate test conditions so that scaled ice shapes are produced on geometrically similar bodies was developed and experimentally verified. (2) Posttest evaluation of the scaling parameters based on the actual test conditions was necessary for accurate evaluation of test results. (3) An icing similitude computer code, SIMICE, was developed to calculate similitude conditions using the verified scaling equations. (4) The equations were applicable over the range of meteorological conditions found in natural icing, with the possible exception of velocity. (5) Velocity is the primary limitation of the scaling equations. To maintain scaled flow fields and droplet impingement characteristics, both the model and full-scale velocities must yield a Reynolds number or = 200,000 and the velocity giving the critical Mach number of the body geometry. (6) At values of dynamic pressure of approximately 1.6 psia, shedding characteristics of the ice accretion were observed to affect the final ice shape. Keywords: Aerodynamics: Thermodynamics; Ice formation; Scaling factors; and Thermal models. Revision to report dated Nov 1985, ADA162226. See also Volume 2, ADB097466. Prepared in cooperation with Sverdrup Technology, Inc., Arnold AFS, TN.