OF ROTOR DYNAMICS ON IN ROTATING - … · Bently Rotor Dynamics Research ... rotor rigs were also...
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DEMONSTRATION OF VARIOUS ROTOR INSTABILITIES (EXHIBIT OF BENTLY ROTOR DYNAMICS RESEARCH CORPORATION LABORATORY RIGS AT SYMPOSIUM ON INSTABILITY IN ROTATING MACHINERY) Agnes Muszynska Bently Rotor Dynamics Research Corporation Mi nden , Nevada 89423 The followi g\papers describe the operation of rotor rigs u d at the symposium exhibit to demonstrate various instability phenomena occurring i n rotating machines. The instability phenomena demonstrated included oil whirl/whip (fig. l), antiswirl (fig. 2), rub (fig. 3), loose rotating parts (fig. 4),. water-lubricated bearing instabilities (fig. 5), and cracked shaft (fig. 6). The rotor rigs were also used to show corrective measures for preventing instabilities. computerized instrumentation. Vibrational response data from the rigs were taken with modern, The rotor nonsynchronous perturbation rig demonstrated modal identification techniques for rotor/bearing systems (fig. 7). Computer-aided data acquisition and presentation, using the dynamic stiffness method, makes it possible to identify rotor and bearing parameters for low modes. The shaft mode demonstrator (fig. 8) presented the amplified modal shape line of the shaft excited by inertia forces of unbalance (synchronous perturbation). The f i r s t three bending modes of the shaft can be demonstrated. The user-friendly software, "Orbits," presented a simulation of rotor precessional motion that is characteristic of various instability phenomena. The data presentation demonstration used data measured on a turbine-driven compressor t r a i n as an example of how computer-aided data acquisition and presentation assists in identifying rotating machine malfunctions. 409 https://ntrs.nasa.gov/search.jsp?R=19860020722 2018-08-17T23:15:23+00:00Z
Transcript of OF ROTOR DYNAMICS ON IN ROTATING - … · Bently Rotor Dynamics Research ... rotor rigs were also...
DEMONSTRATION OF VARIOUS ROTOR INSTABILITIES (EXHIBIT OF BENTLY ROTOR DYNAMICS
RESEARCH CORPORATION LABORATORY RIGS AT SYMPOSIUM ON INSTABILITY
I N ROTATING MACHINERY)
Agnes Muszynska Bent ly Rotor Dynamics Research Corporation
M i nden , Nevada 89423
The f o l l o w i g\papers describe the operation o f r o t o r r i g s u d a t the symposium e x h i b i t t o demonstrate various i n s t a b i l i t y phenomena occurr ing i n r o t a t i n g machines. The i n s t a b i l i t y phenomena demonstrated included o i l whir l /whip ( f i g . l ) , a n t i s w i r l ( f i g . 2 ) , rub ( f i g . 3 ) , loose r o t a t i n g par ts ( f i g . 4 ) , . water-lubricated bearing i n s t a b i l i t i e s ( f i g . 5) , and cracked shaf t ( f i g . 6) . The r o t o r r i g s were a lso used t o show cor rec t ive measures f o r preventing i n s t a b i l i t i e s . computerized instrumentation.
V ibrat ional response data f r o m the r i g s were taken w i th modern,
The r o t o r nonsynchronous per turbat ion r i g demonstrated modal i d e n t i f i c a t i o n techniques f o r rotor/bear ing systems ( f i g . 7 ) . Computer-aided data acqu is i t ion and presentation, using the dynamic s t i f f n e s s method, makes it possible t o i d e n t i f y r o t o r and bearing parameters f o r low modes.
The shaf t mode demonstrator ( f i g . 8) presented the ampl i f ied modal shape l i n e o f the shaf t exc i ted by i n e r t i a forces o f unbalance (synchronous perturbat ion). The f i r s t three bending modes o f the sha f t can be demonstrated.
The user- f r iendly software, "Orbits," presented a s imulat ion o f r o t o r precessional motion t h a t i s charac ter is t i c o f various i n s t a b i l i t y phenomena.
The data presentat ion demonstration used data measured on a turbine-driven compressor t r a i n as an example o f how computer-aided data acqu is i t ion and presentat ion ass is ts i n i d e n t i f y i n g r o t a t i n g machine malfunctions.
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https://ntrs.nasa.gov/search.jsp?R=19860020722 2018-08-17T23:15:23+00:00Z
i l Whirl/Whip Demon
crete Base, 7 -- Speed Controller, 8 - 2, IO 0- S ~ e ~ t r u
ear in¶^ 3 -- Oil Tank,
Figure 2. Anti-Swirl Demonstrator.
Controller,
1 -- Rotor, 2 -- Seal, 3 -- Air Jet, 4 -- Elec- otor, 5 -- Proximity Probes, 6 -- Manometers, 7 -- Concrete Base, 8 -- Speed
9 -- Oscilloscope, 10 -- Digital Vector Filter DVF 2.
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Figure 3. Partial Rotor-toestator Rub Demonstration. 1 -- Shaft, 2 -- Brass Screw Generating Rub, 3 -- X-Y Displacement Proximity Probes, 4 -- Electric Motor, 5 -- Concrete Base, 6 -- Rigid Bearings, 7 -- Acoustic Insulation Box, 8 -- Speed Controller, 9 -- Oscilloscope, 10 -- Digital Vector Filter DVF 2, 11 -- Spectrum Analyzer.
Figure 4. Disk, 3 -- Loose Disk, 4 -- X-Y Displacement Proximity Probes, 5 -- Electric Motor, 6 -- Protection Guard, 7 -- Concrete Base, 8 -- Speed Controller, 9 -- Oscilloscope, 10 -- Digital Vector Filter DVF 2, 11 -- Spectrum Analyzer.
Loose Rotating Part Instability Demonstration. 1 -- Rotor, 2 -- Fixed
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Figure 5. bilities in Fluid Flow Machines. Bearing, 3 -- X-Y Displace~e~t Pro~imity Probes, Base, 6 -- Speed Con~roller, 7 0- Oscilloscope, 8 -- Digital Vector Filter DVF 2,
Rotor with Rubber-Lined Water-Lubricated Bearing Demonstrating Insta- 1 :- Rotor, 2 -- Rubber-Lined ~ater-~ubricat~d
lectric M O ~ O V , 5 -- Concrete
Figure 6. Cracked Shaft Demonstrator. Guard9 4 -- X-Y Displacement Non-contacting Probes, 5 -- Concrete Base, 6 -- Elec- tric Motor, 7 -- Spectrum Analyzer, 8 -- Digital Vector Filter DVF 2, 9 -- Speed Controller, 10 -- Oscilloscope, 11 -- Printer/Plotter, 12 -- Hewlett Packard 9836C Computer.
1 -- Rotor, 2 -- Bearings, 3 0- Safety
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Figure 7. by Perturbation Testing. Lubricated Bearing, Motor9 7 0- Perturba Controller, 10 -- The DVF 2, 13 -- Spectrum Pri nter/Plotter
Laboratory Rig Demonstrating Identification of RotorBearing Parametel-s
Proximity Probes, 5 -- Main Rotor, 6 -9 Main Electric 1 -- perturbation Rotor, 2 -- Keyphasor Probe, 3 -- Oil
c t r i c Motov, 8 -- Pressure Controller, 9 -- Speed rg 11 0- Oscilloscope, 12 -- Ds’gital Vector F i l te r e r , 14 -- ~ @ ~ l @ t ~ Packard 98366 computer^ 15 --
Figure 8. Bearings, 3 -- X-Y Proximity Probes, 4 -- Electric fiotor, 5 -- Concrete Baseg 6 -- Speed Controller, 7 -0 Oscilloscope, 8 --.Digital Vector Fi l ter DVF 2, 9 -- Ampli- f i e r , 10 -- Elastic Rod Demonstrating Shaft Bows 11 0- Servomechanism Translating Iv Amp1 itudes and Frequencies (Polar Coordinates) of the Vertical Signals i n t o Vertical and Horizontal Notion (Cartesian Coordinates) of the Rod Supports.
S h a f t Bow Mode Demonstrator. 1 -- Rotor w i t h Three Disks, 2 -- Rig id
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