MrGoldrick, R.T., "Calculation of Natural Frequencies 

 and Normal Modes of Vibration for a Compound Isolation 

 Mounting System," DTMB Report 1420, July 1960. 



The natural frequencies and normal modes of vibration of a com- 

 pound mounting system are determined. The system consists of an 

 assembly supported by a set of isolation mountings carried by a cradle 

 which is. in turn, supported by another set of isolation mountings 

 attached to the hull of a ship. 



MrGoldrick, R.T., "Calculation of the Response of a 

 Ship Hull to a Transient Load hy Digital Process," DTMD 

 Report 1119, March 1957, 



A digital method of finding the response of a beam-like structure 

 with free ends, such as a ship hull, to an arbitrary load normal to its 

 longitudinal axis is presented. The generality of the solution is pointed 

 out as well as the limitations and need for experimental verification of 

 the validity of the method. 



McGoldrick, R,T., "Comparison between Theoretically 

 and Experimentally Determined Natural Frequencies and 

 Modes of \ ibration of Ships," DTMB Report 906, August 

 19r)4, 



The results of vibration-generator tests and theoretical calcula- 

 tions of natural frequencies and nonnal modes of vibration on eight 

 vessels of widely different types are discussed in this progress report. 

 B> using correction factors for the various modes based on the accumu- 

 lated experimental data, more reliable estimates should be possible in 

 the future. 



McGoldrick, R,T,, "Buoyancy Effect on Natural Fre- 

 quency of \ ertical Modes of Hull Vibration," Journal of 

 Ship Research, July 1957. 



This paper develops a formula for the effect on the natural 

 frequencies of vertical modes of hull vibration of a variable buoyancy 



McGoldrick, R.T., "Determination of Hull Critical 

 Frequencies on the Ore Carrier SS E.J. KULAS by Means 

 of a Vibration Generator," DTMB Report 762, 1951. 



This report describes vibration-generator tests made on the 

 KULAS to determine the cntical frequencies of the hull under light 

 and loaded conditions and in both deep and shallow water. Calculated 

 critical frequencies are also given. 



McGoldrick, R.T., "Rudder-Excited Hull Vibration on 

 I SS FORREST SHERMAN (DD931) - A Problem in Hydro- 

 elasticity," Trans SNAME, 1959. Also DTMB Report 

 U31, June 1960. 



The vibration phenomenon encountered on the FORREST 

 SHERMAN was unusual in that the frequency of the 3-noded hon- 



The cause was found I 

 conceivable explanati. 

 surface flutter conditi. 



over a considerable range of speed, 

 ders. This paper explores several 

 ounts for It as a sub-critical control- 



McGoldrick, P.T., "Ship Vibration," DTMB Peport 

 1451, December 1960. 



This report presents a general treatment of the subject of ship 

 vibration, including both the structural and hydrodynamic phases, 

 with suggested procedures for dealing with vibration problems in the 

 ship's early design stage. 



McGoldrick, R.T. and Curtis, W.F., "Analysis of 

 Vibration in the Propelling Machinery of the Battleships 

 NORTH CAROLINA and WASHINGTON (BB55 and BB56)," 

 DTMB Report 518, March 1945. 



Sea trials of two of this cla 

 vibration of their shafts. Thesi 

 values for various mass-elastic 

 After considering many solutior 

 increased which brought the vit 



s brought attention to excessive axial 

 results were compared with computed 

 approximations of the propulsion system, 

 i, the number of propeller blades were 

 ation down to an acceptable level. 



McGoldrick, R.T,, et al,, "Recent Developments in the 

 Theory of Ship Vibration," DTMB Report 739, Revised 

 Edition, October 1953. 



It i 





this report that by considering the ship hull as a 

 floating beam having shearing and bending Qexibility with a distributed 

 viscous damping proportional to mass, it is possible to derive equations 

 of motion under external forces by the general Rayleigh method which 

 yields a solution in terms of normal modes of motion. 



McGoldrick, R.T. and Jewell, D.A., "A Control-Surface 

 Flutter Study ih the Field of Naval Architecture," DTMB 

 Report 1222, September 1959. 



This study of control-surface flutter was initiated because of 

 serious hull vibration on destroyers of the DD 931 Class, which had 

 been traced to the rudders, A control-surface flutter apparatus was 

 built and tested in the towing basin. Analyses varying in complexity 

 are explored and compared with experimental results. 



McGoldrick, R.T, and Russo, V.L,, "Hull Vibration 

 Investigation on SS GOPHER MARINER," Trans SNAME, 

 Vol, 63, 1955. Also DTMB Report 1060, July 1956, 



Extensive vibration-generator tests were sponsored by SNAME 

 to evaluate the accuracy of the available analytical methods and calcu- 

 lating procedures by comparison of calculated versus measured results. 



MacNaught, D,F., "Discussion of Paper, 'Hull Vibratibn 

 Investigation of SS GOPHER MARINER,' by R.T, McGoldrick 

 and V.L, Russo," Trans SNAME, Vol. 63, 1955. 



Miles, John, "Applications and Limitations of Mech- 

 anical-Electrical Analogies, New and Old," Journal of 

 Acoust. Soc, Am., Vol. 14, 1943. 



The general problem of mechanical-electrical analogies is 

 iscussed. The advantages of Firestone's mobility system is demon- 

 trated. The choice of analogy to be used is usually one of convenience, 

 systems intrinsically make only one analogy possible. An 

 alogy in a system with both electromagnetic and electrostatic coupling 



but 



lily i 



uld I 



sfy 



Ma 



j/ell'i 



Mindlin, R.D. and Deresiowicz, "Timoshenko's Shear 

 Coefficient for Flexural Vibration of Beams," ONR Project 

 NR-064-388, Contract Nonr-266-(09), Tech Report 10, 

 June 1953. 



Molloy, C.T., "Use of Four-Pole Parameters in Vibra- 

 tion Calculations," Journal of .Acoustical Society of 

 America, Vol. 29, Nol 7, July 1957. 



Linear elastic systems which have a single input point and a 

 single output point can be characterized by a pair of simple linear 

 equations involving forces, velocities, and the four-pole parameters for 

 the system. This paper shows how this concept used many years in 

 electrical engineering can also be used for mechanical vibrations. A 

 few specific problems are given. 



67 



