Page 429 - Thomson, William Tyrrell-Theory of Vibration with Applications-Taylor _ Francis (2010)
P. 429

416                                       Classical Methods   Chap. 12

                              12-37  A  torsional  system  with  a  torsional  damper  is  shown  in  Fig.  P12-37.  Determine  the
                                   torque-frequeney curve  for the  system.

                                 g, = lO-*











                                      ^2 = 100                       Figure P12-37.
                              12-38  Determine the equivalent torsional system for the geared system shown in Fig. PI2-38
                                   and find  its natural  frequency.

                                                   d, = l |   1, = 40'
                                          ^    3" dia-
                                                    6  diQ.
                                                           = 10 Ib-in.-s2
                                          Md2-2  12=30"
                                        J2 = 24                      Figure P12-38.
                              12-39  If  the  small  and  large  gears  of  Prob.  12-38  have  the  inertias  J' = 2  and  J”=  6,

                                   determine  the  equivalent single shaft  system  and establish  the  natural  frequencies.
                              12-40  Determine  the  two  lowest  natural  frequencies  of the  torsional  system  shown  in  Fig.
                                   PI2-40 for the following values of 7,  K,  and  n

                                                        7j  =  15 lb  '  in.•  s^
                                                        K^  =  2X  10^  lb  •  in./rad
                                                        J2  =  101b  •  in. -  s^

                                                        K^ =  1.6 X  10^ lb  •  in./rad
                                                        73  =  18 1b  •  in. -  s^
                                                        7^3  =  1  X  10^  lb  -  in./rad

                                                        74  =  6 lb  -  in. -  s^
                                                        K^ = 4X  10^  lb  -  in./rad
                                                 Speed ratio of the drive shaft to axle  =  4 to 1
                                   What  are the  amplitude  ratios of J2  to  7j  at  the  natural  frequencies?
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