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Rash, Larry C.

Publications and source records attributed to Rash, Larry C..

Refined Estimation Of Thermal Tensile Stresses In Bolts

Thermal changes in tensile stresses and strains in bolt and in corresponding compressive stresses and strains in bolted material estimated more accurately by use of equations incorporating two refinements over previous equations. Elasticity of bolted material and radial thermal expansion also taken into account. Refined equations improve design and analysis of bolted joints assembled at one temperature (e.g., room temperature) and in which specified minimum tension must be maintained (and/or specified maximum tension not exceeded) at higher or lower operational temperature.

Rash, Larry C.↗

Strength evaluation of socket joints

This report documents the development of a set of equations that can be used to provide a relatively simple solution for identifying the strength of socket joints and for most cases avoid the need of more lengthy analyses. The analytical approach was verified by comparison of the contact load distributions to results obtained from a finite element analysis. The contacting surfaces for the specific joint in this analysis are in the shape of frustrums of a cone and are representative of the tapered surfaces in the socket-type joints used to join segments of model support systems for wind tunnels. The results are in the form of equations that can be used to determine the contact loads and stresses in the joint from the given geometry and externally applied loads. Equations were determined to define the bending moments and stresses along the length of the joints based on strength and materials principles. The results have also been programmed for a personal computer and a copy of the program is included.

Rash, Larry C.↗

Divergence analysis report for the bodies of revolution model support systems

This report documents the sting divergence analyses of nine different model and model support systems that were performed in preparation for a series of wind tunnel tests at the National Transonic Facility at NASA Langley Research Center in Hampton, Virginia. The models were missile shaped bodies of revolution and the model support systems included a force and moment balance and tapered sting sections. The sting divergence results were obtained from a computer program that solved a two-point boundary value problem which used a second order Runge-Kutta integration technique. The computer solution was based on constant section properties between discrete stations along the sting sections, a procedure was developed and included to evaluate the properties for the minimum number of stations along the tapered sections that would produce no more than one half of one percent error in the divergence results. Also included in the report are development of the aerodynamic input data, listings of all input and output computer data, and summary sheets that highlight the input and the critical sting divergence dynamic pressure for each respective configuration.

Rash, Larry C.↗