Document
General Disclaimer
One or more of the Following Statements may affect this Document
This document has been reproduced from the best copy furnished by the
organizational source. It is being released in the interest of making available as
much information as possible.
This document may contain data, which exceeds the sheet parameters. It was
furnished in this condition by the organizational source and is the best copy
available.
This document may contain tone-on-tone or color graphs, charts and/or pictures, which have been reproduced in black and white.
This document is paginated as submitted by the original source.
Portions of this document are not fully legible due to the historical nature of some
of the material. However, it is the best reproduction available from the original
submission.
Produced by the NASA Center for Aerospace Information (CASI)
Unclas
G3/03 28619
J. J. Reinmann, R. J. Shaw, and W. A. Olsen, Jr.
Lewis Research Center
Cleueland, Ohio
Prepared for the
First International Workshop on Atmospheric Icing of Structures
sponsored by the
Power Research Institute and the U.S. Army Cold
Regions Research and Engineering Laboratory
Hanover, New Hampshire, June 1-3, 1982
OF POOR 4 AIRCRAFT ICING RESEARCH AT NASA J. J. Reinmann NASA Lewis Research Center, Cleveland, Ohio 44135 R. J. Shaw NASA Lewis Research Center, Cleveland, Ohio 44135 c W. A. Olsen, Jr. NASA Lewis Research Center, Cleveland, Ohio 44135 o^ military transports, a few general ABSTRACT aviation aircraft, but no helicopters NASA is again actively involved in (Refs. 1 and 2).
Today, due to technological aircraft icing research. This paper advances in avionics and flight briefly describes the new research activity in: ice protection systems, controls, nearly all general aviation icing instrumentation, experimental aircraft and helicopters can be methods, analytical modelir;g for the equipped to fly IFR. Yet only a few above, and in flight research. The military helicopters have icing renewed interest in aircraft icing has clearances, and no civil heli,copter has come about because of the new need for yet been certified by the FHA for All-WFather Helicopters and General flight into forecasted icing. Many of Aviation aircraft. Because of today's general aviation aircraft are increased fuel costs, tomorrow's certified for icing, but they rely on Commercial Transport aircraft will also ice protection technology that is over require new types of ice protection 20 years old. The relatively small systems and better estimates of the payload fraction and low power margins aeropenalties caused by ice on of these smaller aircraft mean that unprotected surfaces.
their ice protection systems must be The physics of aircraft icing is light in weight and low in power very similar to the icing that occurs consumption. Since small objects on ground structures and structures at accrete ice faster than large objects, sea; all involve droplets that freeze all the deleterious effects of icing on tree surfaces because of the cold happen faster and are more serious on air. Therefore all icing research an unprotected small aircraft: drag groups will benefit greatly Uy sharing rise, torque rise, power loss, lift their research information. deterioration, stall angle decrease, and stall speed increase.
Because of high fuel costs, INTRODUCTION today's large commercial transports need lighter and more efficient ice If an aircraft is to fly safely protection systems. Tomorrow's aircraft will need alternatives to the through icing clouds, it requires protection on those surfaces that hot-air ice protection system because suffer unacceptaole aerodegradation bleed air will tie scarce on the more from ice accretion. During the 1940's efficient high-by-pass-ratio engines or and 1950's, both the NACA and industry nigh speed turboprop engines.
helped solve the icing problems for Thus, the helicopter, general those aircraft that flew IFR aviation, light transport, and (instrument flight rules), which commercial transport aircraft now share included mainly the commercial and common icing requirements: highly tt.Li...u. +.. ..^'
Qi.ALifY
OF POOR for the codes, B. F. Goodrich Co. will effective, lightweigiit, low-power- install an electrothermal heater consuming deicing systems, and detailed blanket on a UH-1H rotor blade section, knowledge of the aeropenalties due to and Lewis will instrument it with over ice on aircraft surfaces.
50 thermocouples between the various IVASA has organized a new aircraft layers of the heater blanket. The icing resarch program at the Lewis UH-1H blade section will be tested on Research Center to help solve the icing an oscillating blade rig in the IRT.
problems for modern aircraft. This new These tests and the heat conduction program is concentrating on (1) new ice codes may help determine proper heater protection systems, (2) new icing power levels and on/off times as a instrumentation, (3) improved king function of outside air temperature and test facilities and testing techniques cloud liquid water content.
(especially for helicopters), and (4) widespread use of large high speed Glycol Fluid Systems. There is computers to lower development and certification time and cost. Our considerable interest in freezing-point- depressant systems. The University of long-range plan is based on recommendations made in several studies Kansas, under a grant from Lewis, has of the icing needs for modern aircraft tested (Ref. 10) the glycol system on (Refs. 3 to 7). This report gives an two modern general aviation airfoils in overview of NASA's current efforts in the IRT (Fig. 3). The systems used the this new icing research program. modern fluid distributor made of stainless steel mesh by TKS, Ltd., of Great Britain. We have also tested a NASA AIRCRAFT ICING PROGRAM fluid distributor made of a porous composite material that offers the Figure 1 shows on the left the potential advantages of lighter weight main elements of NASA's current and lower costs than the stainless aircraft icing research program, and on steel mesh. Further development of the composite distributor is needed before the right the detailed efforts included in each element. We shall briefly it can replace the stainless steel distributor. Another application for cescribe the research efforts in each element. the leading edge fluid distributor is to keep bugs off laminar flow wings.
Ice Protection Systems In a joint program between NASA Langley and Lewis, a fluid distributor will be Pneumatic Deicers for Helicop- installed on a laminar flow wing and tested for bug and ice protection.
ters. Currently, helicopter rotor Lewis is using all test data on the blades use electrotnermal deicers. An glycol system to develop a data base alternative is the pneumatic boot and design procedure for the modern deicer which offers the potential of lower weight, lower power consumption, porous leading edge fluid distributors, which are more efficient than the simpler operating controls, and lower costs. In a joint research program, distributors tested in the 1940's and NASA Lewis and b. F. Goodrich Co. 195U's.
developed pneumatic deicer boots for UH-1H helicopter rotor blades (Ref. Electromagnetic Impulse Deicers.
The electromagnetic impulse system 8). The best deicer boots developed in the IRT (Lewis Icing kesearch Tunnel) offers potential savings in power over tests (Fig. 2) were installed on a U.S. the conventional anti-icing systems Army UH-1H helicopter at the U.S. Army (Ref. 6). The heart of this system Aviation Engineering Flight Activity at consists of a flat spirally wound coil Edwards AF6, California. These boots of copper wire (about number 10 gauge) will be tested on the UH-1H in icing mounted on a 2- to 3-in.-diameter disk next year under a joint program between made of an electrical insulator and the Army, NASA Ames, ano b. F. Goodrich installed inside the leading edge of Co.
she airfoil. The magnetic field of the coil induces eddy currents in the Electrothermal Deicers. Lewis is airfoil skin, causing it to deflect developing one- and two-dimensional rapidly.
transient heat conduction codes to An electromagnetic impulse deicer analyze electrothermal deicer systems system for commercial transports was recently tested in the IRT in a joint (Ref. 9). To obtain validation data
OR1ui'„ra 7 _ r y f€" 13
OF POGIR QUALITY style icing cloud instruments were Lewis/industry program. Data from that compared in the IRT spray cloud to test are being analyzed. Lewis also determine their relative accuracy and has a new effort to develop the impulse their limitations over a broad range of system for general aviation aircraft conditions. The instruments tested and to test it in the IRT. This were primarily those used to determine involves a grant to Wichita State drop size and liquid water content University who will work with Beech (LWC). All instruments ware installed Aircraft and Cessna Aircraft.
and checked out by the user (owner) or the manufacturer of the instrument to Icephobics. Icephobics is the insure that it was operating properly.
generic name given to any material The IRT spray cloud proved to be that, when applied to a surface, adequately repeatable and spatially reduces the adhesive bond between the uniform for the needs of the program.
ice and the surface. Besides reducing the adhesive bond of ice, an icephobic LWC Instruments. The LWC suitable for aircraft also must resist erosion by rain and sand, must not be indicated by all of the instruments tested were compared with the LWC set carried away with the shed ice, and must withstand exposure to weather according to the standard IRT including the sun's heat and calibration. Figure 5 shows that all ultraviolet rays. instruments agree with each other and the old IRT calibration within about As part of a joint program between 120 percent; the laser spectrometers NASA, the Air Force, and the Army, generally exhibit a larger scatter in several icephobic coatings were tested their LWC indications. The data shown in the IRT with the interfacial shear rig shown in Figure 4. However, no were taken at a very low temperatire to avoid any thermal error that causes coating met all of the above criteria.
water run-off.
Lewis currently has a grant with Clarkson College of Technology to Drop Size Instruments. Eight ASSP develop an icephobic cuating. Dr. H.
(Axial Scattering Spectrometer Probe) Jellinek, the principal investigator and three FSSP (Forward Scattering for this grant, successfully developed Spectrometer Probe) laser spectrometers an icephobic coating for the St.
were compared in the IRT spray cloud.
Lawrence Jeaway locks while he was Data from six of these were obtained; working for the Army Cold Regions the others failed for various reasons.
Research and Engineering Laboratory.
The ASSP data showed a scatter of about A special need exists for 14 um over the range of lU to 25 um.
designing experiments to measure ice The FSSP data were about 4 um higher adhesion and the various structural than the ASSP data. Figure 6 shows properties of ice while the IkT cloud what a 14 um variation in droplet size is operating anu at proper airspeed.
caused in ice shape and drag on a NACA While oruplets are striking the test 001[ airfoil (21-in. chord). The ice object and freezing, they release their shape changed significantly and the heat of fusion which sometimes can resulting drag coefficient changed by a result in a mushy water-ice mixture.
factor of five.
The properties of this mixture could differ markedly from the ice that Ice Detectors. Lewis has funded results after shutting off the spray Ideal Research. Inc., (Ref. 11) to cloud and lowering the airspeed, develop an ins -ument to detect ice on causing the mushy ice to freeze. This the surface of an aircraft compone:it procedure could even induce stresses in and to measure the ice thickness and the ice. These properties are needed growth rate. The MIAMI (Microwave Ice in order to better understand and Accretion Measurement Instrument) design mechanical ice removal systems consists of a resonant surface such as pneumatic deicers and impulse waveguide with related electronics and deicers.
a microprocessor. The wave guide, I which mounts flush with the surface, is cing Instrumentation 0.2 in. wide by 1.41 in. long by 0.393 Cloud Instrument Evaluation. In a in. deep. It has a resonant frequency of 6.21 GHz. As ice builds up, the joint program between Lewis and the Air resonant frequency of the waveguide Force Flight Test Center (Edwards AFB, shifts. A plot of the experimental Calif.) a number of modern and old OF POOR QUALITY resonant frequency shift verses ice drag predicted from the empirical thickness is shown and compared to an formula versus the measured drag for empirical curve fit in Figure 7. This the two airfoils over a wide range of curve-fit is programmed into the icing conditions. The data for the microprocessor to calculate ice modern airfoils fall within the rather thickness and ice growth rate. wide spread of results for the older Ideal Research, Inc., has airfoils. The results of the high LWC demonstrated that the MIAMI works in tests, which were only done for the principle. But further development is modern airfoils, show that the required to demonstrate that it can empirical formula seriously distinguish between water and ice, overestimates the drag. These results because under glaze icing conditions point up the need for better analytical both water and ice are present on the methods for predicting airfoil surface. This problem seems to be performance in icing.
solvable.
Testing with Artificial Ice. High Experimental Methods speed computers are now available and must be used to model the ice accretion Icing Research Tunnel. The Lewis process and to analyze the complex flow Icing Research Tunnel (IRT) is the around airfoils having irregular shaped largest icing wind tunnel in North ice caps and rough surfaces that can America (Fig. 8). The IRT has a 6-ft cause flow separation and high by 9 ft wide by 20 ft long test reattachment. To determine what section; a top airspeed of 300 mph; a physics must be included in the refrigeration plant which produces aerodynamic flow model, the surface total air temperatures down to -30° F static pressures must be measured and which provides for year-round around the airfoil including the ice operation; and 77 air atomizing water cap. These surface pressures are nozzles which produce a simulated icing extremely difficult to measure under cloud with ,liquid water contents from icing conditions, so we have replaced 0.5 to over 2 g/m 3 . The IRT test the actual ice on the leading edge with section operates from sea level (at 0 a wooden replica and obtained static mph) to 30OU ft altitude (at 300 mph).
pressures and drag uata in the IRT The IRT was built in 1944; today it is without the icing could (Ref. 13).
in continual use and constantly has a Drag results are shown in figure lU for 2-year backlog of test requests. The both the real ice and the wood replica IRT can test selected full-scale (roughness was simulated with grit) for components such as airfoils and engine both rime and glaze ice. The drag for
it
inlets, and has even tested the artificial ice agrees satisfac- propellers and aircraft engines in the torily with the real ice. Fixed-wing diffuser leg downstream of the main aircraft are often flown with test section.
artificial ice in order to determine the aeropenalties due to ice.
Airfoil Performance in Icing.
Artificial ice may some day be applied There is a universal need for data on to helicopter rotor blades to determine the aerouynamic degradation of aeropenalties.
twu-dimensional airfoils in icing.
From tests in the IRT during the 1940's Helicopter Test Rigs. As and 1950's empirical formulas were mentioned earlier, no civil helicopter developed (Ref. 12) that predicted lift is yet certified by the FAA for flight and drag increments while accounting into forecasted icing. A key reason for chord and thickness of the airfoil, for this lag in technology is the lack liquid water content and temperature of of adequate icing test facilities for the cloud, airspeed, and duration of helicopters and their components.
the icing encounter. We recently slight testing in natural icing clouds tested in the IRT two airfoils is extremely expensive because currently used on general aviation experience indicates that it would take aircraft. One of these airfoils has a several years of winter flying in blunter leading edge that gives higher natural icing conditions to prove that maximum lift coefficientss and "softer" the helicopter meets icing stall characteristics than the older certification criteria, and even longer airfoils that were tested to obtain the to get research type of icing data.
empirical formulas. Figure 9 shows the r,.OALI T V OF POOR new AWT would have two test sections: Two icing simulators exist for a 20-ft diameter section with speeds up testing complete helicopters: the to Mach 1 and a 45-ft diameter section Icing Spray Rig, a ground test facility with speeds up to 5u knots. The high at Uttawa, Canada; and the HISS speed section would test deicers on (Helicopter Icing Spray System), the oscillating, full-scale rotor blades up U.S. Army's inflight icing simulator.
to blade-tip Mach numbers; it would The Ottawa Spray Rig tests helicopters test helicopter inlets with simulated in hover or low-speed transition. The rotor downwash; and it woulo do in HISS tests helicopters forward complete rotor tests on typical scale flight. Both operate only in the short model rotors. The low-speed section winter season and are subject to the would test complete helicopters (with whims of the weather.
truncated blades), and it would have a The Lewis IRT has tested rotor whirl rig for testing full-scale full-scale engine inlets for nearly all rotor blade deicer systems.
U.S. helicopters that fly IN. What the helicopter industry lacks is an Icing Scaling Laws. All icing icing tunnel that can test main rotor simulation facilities have limited blades under simulated flight capabilities in the velocity, size, conditions. In an attempt to see if altitude, droplet size, liquid water the IRT can be useful in testing rotor content, and temperature they can blades, we are building two rotorcraft generally attain. As a consequence test rigs (rig. 11): an oscillating they cannot duplicate all of the g lade rig and a rotating blade rig.
conditions necessary to test an The oscillating blade rig will simulate aircraft component flying through an variations in pitch angle during foward icing cloud. To get around these flight, thereby giving more realistic facility limitations, icing scaling ice shape data on full-scale rotor laws were deriveu in the 195U's (Ref.
airfoil sections. Lift and drag data 14); however, these relationships have can be obtained for these iced-up rotor never been properly verified. Proper blades. Tois aerodynamic data may be experimental verification is extremely useful in predicting performance difficult because of serious facility degradation of helicopters without ice and icing instrument limitations.
protection. The oscillating rotor In an attempt to verify the icing blade in the IRT may also prove useful scaling laws, Lewis and AEUC (Arnold for initial testing of deicer systems Air Uevelopment Center, Tullahoma, even though the oscillating rig does Tenn.) have entered into a joint not simulate centrifugal forces and the Research program. The experimental air ,peed is less than Mach 0.4 in the verification uses the complementary IRT.
capabilities of the large low speed The rotating blade test rig will Lewis IRT and the AEUC small high-speed be used to test an OH-58 tail rotor free jet. Lewis is performing research (about 5 ft in diameter). For the on the energy balance, the heat OH-58 blade, rotating blade test transfer coefficients, and the catch results will ue compared with efficiency of airfoils to improve the oscillating blade test results to existing icing scaling laws. AEUC is determine the importance of centrifugal testing several spray nozzles to find force and Mach number on ice shape.
one that produces the small droplets the main usefulness of the rotating required for testing small scale models
blade rig will be to study the ice
and also to improve all icing formations and to measure the simulation facilities. Verification aerodynamic degradation caused by the tests will consist of testing a series ice. Model rotors could also be tested of airfoils under several sets of icing in the IkT, but the icing scaling laws tunnel conditions that are predicted by must be verified and nozzles that the scaling laws to give equivalent produce water droplet volume median drag and ice shape results.
diameters less than lU are p m Verified icing scaling laws would required. We are working toward these (1) permit accurate tests at actual goals.
facility conditions which duplicate Lewis has been advocating that results of conditions unattainable by their now dormant Al"itude Wind Tunnel that facility, and (2) permit tests of (AWT) be rehabilitated into an icing small-scale models of aircraft and research (or extreme weather) and propulsion win tunnel (rig. 12). The OF POOR QUAILITY The University of Uayton Research rotors to determine the aeropenalties Institute is developing an ice of icing.
accretion modeling code (Ref. 17) which ;,ill calculate two-dimensional ice Analytical Methods accretion shapes on airfoils for rime The NASA aircraft icing research through glaze icing conditions. The effort includes extensive aircraft approach extends the work of icing analysis. The long-term goal is Stallabrass and Lozowski (Ref. 18) and to use computers to predict the details Ackley and Templeton (Ref. 19). The of an aircraft icing encounter.
code is compatible with the water Computer codes will oe developed to droplet trajectory code developed by predict overall aircraft performance FWU, and allows the airfoil flow field aegradation due to ice accretions on and resultant collection efficiency to unprotected surfaces and the resultant be recomputed as the ice accretion changes in aircraft handling changes the airfoil contour.
characteristics. Uther codes will be The University of Toledo is developed to design ice protection developing one- and two-dimensional systems and analyze their performance. transient heat conduction cones to Today's large, high-speed digital model electrothermal .,eicers. A computers were not available to the preliminary version of the NACA icing researchers in the 194U's one-dimensional code is given in and 195U's, and up until 1980 virtually Reference 9. These codes include a no icing analysis cuues were published moving water-ice interface.
in the open literature. With the The Uhio State University is increasing costs of conducting tests in developing a capability for predicting icing wind tunnels and in icing flights aerodynamic performance degradation of there noo is a strong motivation to airfoils due to ice accretions (Ref.
develop an aircraft icing analysis 2U). They start with existing rethodology to hold test programs to aerudynamic analysis codes fur the minimum.
airfoils, and modify them wherever Currently we are developing some needed to model the flow around of the required codes and verifying airtuils with ice accretions. As a their accuracy with appropriate separate activity, Uhio State is experiments. These codes are being developing a simplified method to developed through a combination of predict overall aircraft performance in-house efforts and various grants and tnat uses the results of the various contracts. Figure 13 indicates the other two-dimensional codes being developed.
large number of computer codes ruyuired. Also shown are some (but by Texas A&M University is using the no means all) of the required fixed-wing methodology developed at intertaces. The figure also shows Uhio Jtate University and extending it to calculate the perfurmance areas ut _urrent research in NASA.
degradation of propellers and FwU Associates, Inc., is developing a particle trajectory cone helicopter rotors, uoth in hover and in forward flight (Ref. 21) .
(Ref. 15) to calculate two-dimensional trajectories about single- a.iu multi- As Figure 13 indicates, many element airfoils, two-dimensional additional computer codes remain to be inlets, and axisymmetric inlets at developed. before many of them can be angle of attack (symmetry plane only. developed, fundamental experiments must The flow tields are calculated using be conducted to gain a better dpprupridte Uut,glas Aircraft potential unuerstanding of the physics to guide flow cuues.
the modeling efforts. Also of critical Atmuspheric Science Associates has importance is accurate verification ueveluped a three-dimensiunal particle data to determine computer code trajectory code which is capaole of capabilities and limitations.
calculating trajectories about three- Unfortunately little verification data ui,,crisionUl nonlifting and (Ret. lb) exist and getting it will require the lifting uodies. The code can calculate uevelopment of new icing simulation water droplet trajectories about the facilities, test rigs, and eunplete aireratt. Again, appropriate instrumentation capabilities.
putential flow field codes developed by uuuglas Aircraft are used to predict the aircraft flow field.
OF PCOR
Flight Research 14 levels in altitude and 51 sec computation time interval. After each Lewis has started an icing icing flight, Lewis gives Langley the location arid altitude where the Twin research flight program usin NASA's Utter encountered icing. Langley uses Twin Utter airplane (Fig. 14^. It will this data to validate MASS by be flown out of Lewis during the icing season from November through April. backcasting the conditions at the The flight program is intended to specified location of the icing insure that researchers conducting encounter.
icing tests in the IRT or developing Airplane Performance. NASA and computer codes in support of icing have first-hand knowledge of how their the Ohio State University will conduct results compare with flight test inflight icing experiments to measure results in real icing conditions. lift and drag degradation of the Twin Otter's wings, and also overall Validation Data for Icing performance loss. Ohio State will Simulation Facilities. There does not install a heated wake survey probe and seem to have been any systematic a static pressure belt on one of the attempt to prove that icing simulators Twin Otter's wings. Thrust horsepower do a reasonable job of duplicating the measurement techniques will be natural icing conditions. Lewis plans developed. Flight results will be to obtain during flights in natural compared with similar results of tests icing conditions, ice shapes on in the IRT on a Twin Utter wing section.
standard cylinders and airfoils that any icing simulator can try to reproduce. CONCLUDING REiW KS For example, the same airfoils and cylinders used in flight will ue As you can see from this review of installed in the IRT where flight icing NASA's new icing research program, it conditions , (airspeed, LWC, drop size, is broaabased and covers both basic and temperature) will be duplicated.
research and engineering applications.
Drag, ice shapes, and ice growth Undoubtedly you have seen areas in the characteristics obtained in the IRT NASA program to which some of your own will be compared with those from research applies and vice versa. We natural icing. The flight and IRT data would like to take the opportunity comparisons will measure the IRT's provided by this international meeting auility to simulate natural icing to explore possible ways that we could conditions.
cooperate, such as, comparing computer code predictions, or providing Instrument Evaluation. This experimental data for guiding and flight program affords an opportunity validating analytical methods, conducting joint experiments, comparing to compare several modern cloud instruments with one another and also experiences with various icing instruments, or devising experimental with the rotating multicylinders and oil slide instruments that were used in techniques for measuring structural ten 194U's and 1950's. The Twin Utter properties of ice under actual will be equipped with all of the modern operating conditions in the IRT.
flightworthy cloud instruments.
REFERENCES Icing Cloud uata. un eacn icing flight NASA will collect icing cloud 1. keinmann, J. J.: Selected data and give it to the FAA who is collecting and correlating icing cloud bibliography of NACA-NASA Aircraft data taken at lower altitudes with Icing Publications. NASA TM-131651, modern instrumentation. 1981.
2. Bowden, U. T.; Gensemer, A. E.; and oleteurulogy. NASA Langley has Skeen, C. A.: Engineering Summary developed a numerical code (Ref. 22) to of Airframe Icing Technical Data.
forecast the future state of the FAA-ADS-4, Federal Aviation Agency, atmosphere at mesoscdle. The code is 1963.
entitled MASH (hiesoscale Atmosphere Simulation System). MASS uses a 5U km grid spacing over North America, with IS ORiGNAL FAME OF POOR QUALITY 3. Peterson, A. A.; Dadone, L.; and 16. Norment, H. G.: Calculation of Bevan, A.-. Rotorcraft Aviation Water Drop Trajectories to and Icing Research Requirements.
about Arbitrary Three-Dimensional Research Review and Bodies in Potential Airflow. NASA Recommendations.
(0210-11662-1, CR-3291, 1980.
Boeing Vertol Co.; NASA Contract 17. MacArthur, C. D.; Keller, J. L.; NAS3-22384.) NASA CR-165344, 1981.
and Luers, J. K.: Mathematical 4. Breeze, R. K.; and Clark, G. M.: Modeling of Ice Accretion on Light Transport and General Airfoils. AIAA Paper 82-0284, 1982.
Aviation Aircraft Icing Research 18. Lozowski, E. P.; Stallabrass, J.
Requirements. (NA-81-11U, Rockwell R.; and Hearty, P. F.: The Icing International Corp.; NASA Contract of an Unheated Non Rotating NAS3-22186.) 1981.
NASA CR-165290, Cylinder in Liquid Water Koegeboehn, L. P.: Commercial 5.
Droplet-Ice Crystal Clouds.
Aviation Icing Research LTR-LT-96, Natural Research Council Requirements.
NASA CR-165336, 1981.
of Canada, 1979.
6. Rotorcraft Icing--Status and 19. Ackley, S. F. and Templeton, M. K.: Prospects. AGARU AR-166, 1981.
Computer Modeling of Atmospheric 7.
Engineering and Development Program Ice Accretion. CRREL-79-4, Army Plan--Helicopter Icing Technology Cold Regions Research and Research.
FAA-ED-18-d, Federal Engineering Lab., 1979.
Aviation Administration, 1981.
20. Bragg, M. B.; Gregorek, G. M.; a.id 8. Blaha, B. J.; anu Evanich, P. L.: Shaw, R. J.: An Analytical Pneumatic boot for Helicopter Rotor Approach to Airfoil Icing. AIAA Deicing. NASA CP-217U, 1980.
81-0403, 1981.
9. DeWitt, K. J.; and 8aliga, G.: 21. Korkan, K. U.; Uadone, L.; and Numerical Simulation of Shaw, R. J.: Performance One-Uimensional Heat Transfer in Degradation of Propeller/Rotor Composite bodies with Phase Systems Due to Rime Ice Accretion.
Change.
NASA CR-165607, 1982.
AIAA-82-0286, 1982.
lU. Kohlman, U. L.; Schweikhard, W. G.; 22. Kaplan, M. L.; et al.: A Mesoscale and Aluright, A. E.: Icing Tunnel Eighth Order Numerical Modeling Tests of a Glycol-Exuding Porous System and the "Red River" Tornado Leading Edge Ice Protection System Outbreak of 1979, Parts I and II.
on a General Aviation Airfoil.
Presentea at the 12th AMS (KU-FRL-464-1, Kansas Univ. Center Conference on Severe Local Storms, for Research, Inc.; NASA Contract (San Antonio, Texas), Jan. 11-15, 14AG3-71.) NASA CR-165444, 1981. 198?.
11. Magenheim, b.; and Rocks, J. K.: Uevelopment and Test of a Microwave Ice Accretion Measurement Instrument (MIAMI). NASA CR-bATI'- 9288U, 1981.
12. Gray, V. H.: Prediction of Aerodynamic Penalties Causea
by Ice
Formations on `carious Airfoils.
NASA TN U-2166, 1964.
M.
13. Bragg, b.; Gregorek, G. M.; and Shaw, R. J.: W e nd Tunnel Investigation of Airfoil Performance Uegradation Due :o Icing. AIAA-82 -obd2, 1982.
14.
Uodson, E. U.: Scale Model Analogy for Icing Tunnel Testing.
06-7976, Boeing Airplane Company, 1966.
16. Frost, W. F.; Chang, H.; Shieh, C.; and Kimble, K.: Two Uimensional Particle Trajectory Computer Program. NASA CR to be published.
..i
OF POOR QU
ALITY *ICE PROTECTION SYSTEMS PNEUMATIC DEICERS FOR HELICOPTERS - ELECTROTHERMAL DEICERS - GLYCOL FLU.0 SYSTEMS - ELECTROMAGNETIC IMPULSE DEICERS ICEPHORICS ICING INSTRUMENTATION - CLOUD INSTRUMENT EVALUATION ICE DETECTORS 0E1l PERIMENTAL METHODS ICING RESEARCH TUNNEL - AIRFOIL PERFORMANCE Ik ICING • TESTING WITH ARTIFICIAL ICE • HELICOPTER TEST RIGS ICING SCALING LAWS 0 ANALYTICAL METHODS - COMPUTER CODES FOR *WATER DROPLET TRAJECTORIES •ICE ACCRETION MODELING OAERO PERFORMANCE PENALTIES •TRANSIENT DEICER ANALYSIS 0 FLIGHT RESEARCH • VALIDATION DATA FOR ICING SIMULATION FACILITIES - INSTRUMENT EVALUATION - ICING CLOUD DATA METEOROLOGY CO - 82 - 13130 AIRPLANE PERFORMANCE FIGURE 1. - Elements of NASA's AlrLrall Icing Froyram• f.qure 2 - Pneumaf^c boot deicer on UN- 1H rotor blade, and wake surrey probe n the LeRL Icing kesearch tunnel ORICINAL PAGr-' BLACK AND WHITE Pf ;OTOGRAPN figure 3. - Glycol fluid distributor iporous slain less stee p on leading edge of *trig In the IeRC Icing Rnoarch Tunnel rig In IcohoD-cs inter'st &I ,near stress lest Ike IaRC king figure Q 0HEer t f` tu"neI
-1 i' Y
-1
OF POOR QI
,H CIL 01010 011 0TATG I 011 AN , ► ^0 r:Ar 0 1.AYA n n .ro.•^ r
»
.FIIFFCI U AOAFIM(MT n ^^/' Is— ^^ '70•. to 1s v .'o = o,C 1 _ L—L ] L_L 1 1 _ :_ 1 ..L s 10 1S M 7s s 10 +s M A e )1 ^ ^ 111DH 110IIMOYNT ^ ij yQ C F ^ ty ^ If i 10—,o t y 0 _ l 1 _LJ o I CD42.11116
1 10 tl » )t s to '1 70 )t
L W c ytm tot tlgure S. - Results of tests Comparing several h0u10-loter- conlent meters In the Lewis IRT, D1100 SIZE C D IMIC,IOMS I OTe )5 Ir --- Ots , D11r 000, 0012 ANIFOA -^ \ 21 w1 LHO11D ANSO((0. 110 mpe AM MAP, MM V. L WC I I Wall', Tr1( I Inb. AItOI(. e' CDV-0111 1 1gure 4 (Mr-1 at cloud volume M eow oroplel ure an 1ce snap WW dreg, from meesurements in the LA1s 1Ry.
n OF POUR QUALITY w , 11.»R000 (^^ __L.___l. 1 J '. 1DRO a w ,a .0 xe Kf , »K.MRR w.M w r r[aw[o- xIM t.r r.,.:: snot[ sROA w `rrr^ R[.DOu, IM1 60 300 no cc^r w -IfI^ I'M RRR ice thickness for the ( Iqu Ct 7 ROUIIon%h10 p rfnen rrton•nt Irpu•n( t shift •n• r f rtnt IntfruMfIll (MIAMI 1.
%%(r%& g ICf ACC rfhOn h4[su 11011 CRMrts ICING RESEARCH TUNNEL, SHOP AND OF/.CI CONTROL 8000 W nit (».rtt I KIM tDD •r» ntt nt^ rc,w.l J 1rR.,t ff CiOM •.^ 5.1^ 1 J 0001 AnUtl l0» , RU R/100 — — 1rQr ^` y FRRurR l • uq KNff4W if the LOWS Klnq 11R1••rch tuwwl
:^ ail`
OF i a n ONACA 61, A615 LINE Of M ? PERFECT AGVEMENT C q NACA 6e SERIES (MODIFIED.
/ (SOLID Sr MBOLS DENOTE W NIGH LIOUID WATER t CONTENT DATA u • / i u / SOMA IN NACA DATA O Q Of O ^^ o+ Or oo a ^:pMEAS 4E0 CD-62.13136 Figure 9, - Predicted frig Increments Due to Ice accretion (from NASA TN D-2166) vertu, drag Increments measured In the Lewis IRT.
WOOD ROUGH 020 ICE 020 / / i WOOD % ICE U D15 ROUGH 1^ E ^ Ot alt Z W i a 0+0 ^— 010 RIME ICE GLAZE ICE U 0 005 D:
L
0 0
5 10 15 5 10 15 ANGLE OF ATTACK dog ANGLE OF ATTACK. dog CD-82-13133 Figure 10 • Drag increments from real Ir! compaw v,i;h t he uray Increments f rom wooden replicas of the Ice.
OIt;''2L^33
0,1jAU i Y
OF PC,^ : ROTATING BLADE RIG OSCILLATINGBLADE RIG FULL SCALE TAIL ROTOR I I CnOCr Al c UAiu onTnG I I PLAN VIEW 0-3017 -gym 0 3000 rpm C D-8 2-13132 Figure 11. - Rotor blade test techniques being developed for the Lewis IRT.
WATER SPRAY SYSTEM 45'D LOW SPEED TEST SECTION DRIVE FAN COOLING COILS DRIVE MOTOR- I / ^ i STEAM i
SLOTS
HEATED TURNING i VANES I ENGINE EXHAUST _/ `WATER SPRAY TEST SECTION REMOVAL SCOOP ) SYSTEM 20' D., 40' LONG CD-82-13129 Figure 12 - Flow circuit For proposed renabilllabon of the Lewis Altitude Wind Tunnel IAWTI.
OnEGi^a-.:.
OF POOR `, , AERODYNAMIC FLIGHT, PERFORMANCE ENVIRONMENTAL PENALTIES CONDITIONS AIRCRAFT PARTICLE ICE FLOW FIELD ACCRETION PERFORMANCE TRAJECTORY AERODYNAMIC Boot LOADS GEOMETRY ON KE INTERNAL — NEAT TRANSFER ELECTRO- NOT GAS MIC ROWAVE THERMAL SYSTEM SYSTEM SYSTEM SHED ICE 4 CHAR INCDING – - MECHANICAL ELECTRO C DICATES AREA OF CURRENT COMPUTER CODE DEVELOPMENT F g EEZING PT BY NASA L*PC IC EDNOBICS DEPRESSANT SYSTEM CD-B2-13126 Figure 13. - Flow Chart showing NASA's methoaoiogy for aircraft Icing analysis.
Figure Id - The NASA Icing flight research aircraft.