Page 57 - Thomson, William Tyrrell-Theory of Vibration with Applications-Taylor _ Francis (2010)
P. 57

44                                            Free Vibration   Chap. 2


                              2-26  The engine-valve system of Fig.  P2-26 consists of a rocker arm of moment of inertia  7,
                                  a valve of mass  m ,, and a spring spring of mass  m^. Determine its effective mass at  A.


                           ms






















                                                                     Figure P2-26.  Engine valve  system.
                              2-27  A  uniform  cantilever  beam  of  total  mass  ml  has  a  concentrated  mass  M  at  its  free
                                  end.  Determine  the  effective  mass  of  the  beam  to  be  added  to  M  assuming  the
                                  deflection  to  be  that  of  a  massless  beam  with  a  concentrated  force  at  the  end,  and
                                  write  the  equation for its fundamental  frequency.
                              2-28  Repeat  Prob.  2-27 using the  static deflection


                                                    y(x)  ==              4-  3
                                                          24  El
                                  for the  uniformly loaded  beam,  and compare with previous result.
                              2-29  Determine  the  effective  rotational  stiffness of the  shaft  in  Fig.  P2-29  and  calculate  its
                                  natural period.






                                                                     Figure P2-29.
                              2-30  For  purposes  of analysis,  it  is  desired  to  reduce  the  system  of Fig.  P2-30  to  a  simple
                                  linear spring-mass system of effective mass   and effective stiffness   Determine
                                     and    in terms of the given quantities.
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