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This paper presents an analysis of measurements of drill-pipe deformation in the slip area. Drill pipe was loaded in excess of the load at the minimum yield strength with the pipe in VARCO Type SOL and Type SDXL slips. A VARCO Type MSS solid master bushing was used with the type SDL slips and the master bushing of a VARCO KMPC unit was used with the Type SDXL slips. Measurements were made on the reduction in pipe diameter in the slip area as a function of load. Values of load which caused inelastic deformation of the pipe are determined and compared to the values previously calculated from theory.

During the first or booster stage of flight many liquid-propellant rockets have experienced severe longitudinal vibrations caused by a closed loop interaction between the first longitudinal structural mode and the dynamics of the propulsion system. This, "POGO" instability, reviewed in Reference 1, has been the subject of intensive research since it was first encountered. One of the most important transients in the dynamic modelling of the propulsion system is the "cavitation compliance" of the turbopumps [3] defined as the negative of the derivative of the cavity and bubble volume in the pump and its suction line with respect to the section pressure. Thus, it describes the oscillatory source/sink behavior of the pump due to changes in the cavity volume. Past analyses [1, 2] have suggested dividing this compliance into two components corresponding to the two major types of pump cavitation, namely blade cavitation and back-flow cavitation. The purpose of this paper is to present some preliminary results of theoretical calculations of blade cavitation compliance. The most satisfactory starting point would be a theory for unsteady cavitating flow in a cascade. Whilst work on this is in progress at the present time, the low frequency or quasistatic approach based on existing steady flow theory is much simpler and in itself yields interesting results.

During the first or booster stage of flight many liquid-propellant rockets have experienced severe longitudinal vibrations caused by a closed loop interaction between the first longitudinal structural mode and the dynamics of the propulsion system. This, "POGO" instability, reviewed in Reference 1, has been the subject of intensive research since it was first encountered. One of the most important transients in the dynamic modelling of the propulsion system is the "cavitation compliance" of the turbopumps [3] defined as the negative of the derivative of the cavity and bubble volume in the pump and its suction line with respect to the section pressure. Thus, it describes the oscillatory source/sink behavior of the pump due to changes in the cavity volume. Past analyses [1, 2] have suggested dividing this compliance into two components corresponding to the two major types of pump cavitation, namely blade cavitation and back-flow cavitation. The purpose of this paper is to present some preliminary results of theoretical calculations of blade cavitation compliance. The most satisfactory starting point would be a theory for unsteady cavitating flow in a cascade. Whilst work on this is in progress at the present time, the low frequency or quasistatic approach based on existing steady flow theory is much simpler and in itself yields interesting results.

This paper summarizes a recent sequence of theoretical investigations of plane and spatial load-transfer problems in linear elastostatics. Whereas the two-dimensional problems dealt with here have a particular relevance to aircraft structures, those concerning the transfer of load between a bar and a three-dimensional elastic medium are primarily of interest in connection with civil engineering structures and have a bearing on the mechanics of fiber-reinforced materials. An attempt is made to assess the role of alternative mathematical models in the treatment of the physical problems under consideration, to sketch the essential features of the required analysis, and to discuss the principal results obtained.

During the first or booster stage of flight many liquid-propellant rockets have experienced severe longitudinal vibrations caused by a closed loop interaction between the first longitudinal structural mode and the dynamics of the propulsion system. This, "POGO" instability, reviewed in Reference 1, has been the subject of intensive research since it was first encountered. One of the most important transients in the dynamic modelling of the propulsion system is the "cavitation compliance" of the turbopumps [3] defined as the negative of the derivative of the cavity and bubble volume in the pump and its suction line with respect to the section pressure. Thus, it describes the oscillatory source/sink behavior of the pump due to changes in the cavity volume. Past analyses [1, 2] have suggested dividing this compliance into two components corresponding to the two major types of pump cavitation, namely blade cavitation and back-flow cavitation. The purpose of this paper is to present some preliminary results of theoretical calculations of blade cavitation compliance. The most satisfactory starting point would be a theory for unsteady cavitating flow in a cascade. Whilst work on this is in progress at the present time, the low frequency or quasistatic approach based on existing steady flow theory is much simpler and in itself yields interesting results.

Theoretical expressions have been derived for the relations between gas absorptivities and emissivities for the limit of zero optical depth and for the following models of vibration-rotation bands: bands with constant average absorption coefficients and well-defined widths; just-overlapping spectral lines; non-overlapping dispersion lines with constant collision half-width and either regular line spacing or with lines of equal intensity; randomly distributed spectral lines with dispersion contom; non-overlapping Doppler lines with either regular line spacing or with lines of equal intensity; randomly distributed Doppler lines for a special {unrealistic} assumption relating to the temperature dependence of the effective mean line spacing; non-overlapping spectral lines with combined Doppler and collision broadening, constant collision half-width and either regular line spacing or with lines of equal intensity. The theoretical formulae have been shown to provide a good correlation for the available experimental data on CO_2, H_2O and CO.