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Various commercial surface finishes are produced on steel shafts and in Part 1 it is found that the finish has little effect on the operation of a journal bearing in the region of hydrodynamic lubrication but does markedly affect the load capacity. In Part 2 a chemical method of detecting iron in oil is developed with a sensitivity of one part in ten million. This method is used to measure the iron removed during “running-in” from shafts with different surface finishes and under different loads.

In order to achieve a better understanding of the physical mechanism of interaction between free convection and sound, an experimental investigation of the local heat-transfer coefficient around the circumference of a heated horizontal cylinder, both in the presence and absence of a strong stationary sound field, has been carried out. The results show that superposition of intense sound upon the free-convection temperature-velocity field about a heated horizontal cylinder increases the heat-transfer coefficient both on the under and upper portions of the cylinder’s surface. In the presence of a sound field for which SPL = 146 db (re 0.0002 microbar) and f = 1500 cps, the maximum measured increases in the local heat-transfer coefficient on the under and upper portions of a 3/4-in-diam cylinder—relative to the free convection case at the same temperature potential—were found to be approximately 250 and 1200 per cent, respectively. A comparison of these results with earlier flow-visualization studies indicates that the relatively large percentage increase in the heat-transfer coefficient on the upper portion of the cylinder is caused by the oscillating vortex flow which is characteristic of thermoacoustic streaming. The reasons for the increase in the heat-transfer coefficient on the lower portion of the cylinder appear to be: (a) An increase in laminar boundary-layer velocities (steady components) in this region; and (b) modification of the boundary-layer temperature profile due to acoustically induced oscillations (unsteady components) within the laminar boundary layer. The experimental data presented can be used to check the validity of future analytical investigations of thermoacoustic phenomena.

In a previous publication the authors described a new type of acoustic streaming, called thermoacoustic streaming, which occurs near a heated horizontal cylinder in the presence of horizontal transverse sound fields. In the present paper, quantitative experimental results are presented, which show that thermoacoustic streaming causes a marked increase in the coefficient of heat transfer from a heated cylinder; for a given temperature potential, the superposition of a sound field can increase the heat-transfer coefficient by a factor of 3, relative to the free-convection heat-transfer coefficient in the absence of sound. An empirical equation is provided by means of which the coefficient of heat transfer from a horizontal cylinder in the presence of horizontal transverse sound fields can be computed for many cases of practical interest.

A basic analysis is given of the close-spaced vacuum diode operating as a direct converter of heat to electricity. This analysis is arranged to yield the characteristics of this engine when operating at maximum efficiency. Values of the various parameters are chosen to produce conservative design charts. For a fixed collector temperature and fixed collector work function, two representative design charts are given. These charts permit the designer to estimate very rapidly the optimum performance characteristics, such as efficiency, power to load, current, voltage, conductance of load, etc., as a function of emitter temperature, over a range from 1200° to 1700°K.

The first part of a program to obtain reliable data on the rate of heat transfer to air moving at supersonic speeds in a tube has been devoted to measurements made on adiabatic supersonic flow of air in a tube. The details of these measurements have been described in a previous paper. The calculated quantities such as the local apparent friction coefficient, recovery factor, Mach number, and so forth, were obtained from the simple one-dimensional flow model for which the properties of the stream are uniform at any section, and boundary-layer effects are ignored. The analysis of some of the same data given in the previous paper is undertaken here with the aid of a simplified two-dimensional flow model. The supersonic flow in the tube is divided into a supersonic core of variable mass with the fluid remaining in the core undergoing a reversible adiabatic change of state, and a laminar boundary layer of variable mass. The compressible laminar boundary layer increases in thickness in the direction of flow, and then undergoes a transition to a turbulent boundary layer. The two-dimensional flow model is limited here to the region where a laminar boundary layer appears to be present in the entrance region of the tube. The results of the analysis based on the two-dimensional flow model indicate that where the flow in the tube boundary layer appears to be laminar, the measured pressures and temperatures in the tube for adiabatic supersonic flow of air could have been predicted, with sufficient accuracy for engineering problems, from measured data for supersonic flow of air over a flat plate with a laminar boundary layer, and with zero pressure gradient.

For the past few years a program has been under way to obtain reliable data on the rate of heat transfer to air moving at supersonic speeds. The investigation was limited to air flowing at supersonic speeds in a round tube. The program was divided into two separate parts, the first for measurement of the adiabatic wall temperatures of a supersonic stream and the second for the heat-transfer rate. The first part of this program is described here. The details of three experimental test combinations used to measure the adiabatic wall temperature and local state of a supersonic stream of air are presented. The experimental data for forty runs, in the form of measured pressure and temperature distributions, are included. The range of diameter Reynolds number covered is from 0.15 × 105 to 5 × 105. The length Reynolds number extends to 120 × 105. The Mach number at the inlet to the round tube is about 2.6. The calculated quantities such as the local apparent friction coefficient, recovery factor, local Mach number, and so forth, are obtained from the simple one-dimensional flow model for which the properties of the stream are uniform at any cross section of the tube and boundary-layer effects are ignored. A subsequent paper deals with the calculation of these quantities when account is taken of the boundary-layer growth in the tube on the basis of a two-dimensional flow model.

Four patients are described with metabolic defects on the paths of triglyceride breakdown associated with excessive storage of triglyceride in adipose tissue. In one infant noradrenaline(10−5M) poorly stimulated the activity of adenyl cyclase in subcutaneous adipose tissue in the periphery compared to abdominal tissue (P < 0.05); and this was associated with excessive accumulation of triglyceride in the periphery. In three other generalized obese patients of a kindred, isoprenaline (10−5M) stimulated the activity of adenyl cyclase in subcutaneous adipose tissue as judged by normal increments in tissue levels of cyclic-AMP but this failed to activate the triglyceride lipase; seen as a reduced output of glycerol compared to obese controls (P < 0.01). A provisional classification is proposed for the metabolic defects of triglyceride breakdown based on the separate stages of lipolysis and includes the rare defect of triglyceride breakdown already described in the literature as Wolman's disease.

The article presents the essay posted at the Headquarters of the Engineer Replacement Training Center (ERTC) about the ERTC operations in Fort Leonard Wood, Missouri. The essay is addressed to all the Unit Commanders of the ERTC. It recognizes the completion of the fifth year of Annual Unit Training and the accomplishments of the men, women and officers who have created a favorable reputation.