Hunter Rouse

Experiments on two-dimensional flow over a normal wall

Measurements of the velocity, pressure, and turbulence behind a series of normal plates in the uniform test section of an air tunnel are described, the oscillation of the wake being prevented in all but one test through use of symmetrically located tail plates. By a combination of experimental and computational techniques, details of the pattern of flow over a wall on a plane boundary in an infinite fluid are closely approximated. A significant difference is indicated between the characteristics of such a flow and those of the flow past an isolated plate with oscillating wake.

Jet diffusion in the region of flow establishment

In the flow-establishment region of an air jet issuing with an efflux velocity of about 35 ft./sec from a 1.0 ft. diameter nozzle into still air, measurements were made of mean axial and radial velocities, mean static pressure, turbulence intensities, turbulent shear, and pressure fluctuation. For the measurement of the latter a pressure probe using a ceramic piezo-electric tube was developed. Also included in the measurements were the temporal mean gradient and autocorrelation of the axial-velocity fluctuation and the intermittency factor. The fluctuating-pressure and turbulence-intensity fields were observed to be closely similar in form. Through use of the measured distributions of mean-flow and turbulence characteristics, all terms of the integral and differential forms of the momentum and mean-energy equations were evaluated throughout the region. The results are presented herein by curves of variation of each of the terms as they appear in the corresponding equations.

Free Convection over Parallel Sources of Heat

One phase of a fundamental investigation of convection over point and line sources of heat, conducted through the past decade at the Iowa Institute of Hydraulic Research, simulated a method of fog dispersal used for the landing of aircraft in England during the war. This involved the release of heat from parallel lines of burners, the convection from which produced characteristic patterns of mean flow and of heat intensity above the burners. Experiments described in this paper consisted of the measurement of the velocity distribution and the temperature distribution at various model scales and rates of heat generation. The results have been reduced to dimensionless diagrams of the two distribution functions which satisfy the elementary continuity and impulsemomentum requirements. From these diagrams generalized families of stream lines and isotherms for the mean motion above the sources have been plotted. The general functions reveal the basic pattern of convection and permit the approximate evaluation of velocity and temperature rise for any desired combination of the independent variables.

Model Techniques in Meteorological Research

Scale-model investigations of fluid motion have long since proved their worth in such widely varied fields as aeronautics, ballistics, hydraulics, and naval architecture. New aircraft, projectiles, turbines, spillways, and ships are almost invariably tested at reduced scale before final acceptance of design, and prototype behavior is being predicted with ever-increasing accuracy. Particularly in the field of flood control and river regulation, economies of construction or improvements in design which model studies generally reveal have offset the costs of the studies many times over. It is therefore hardly surprising that meteorologists frequently wonder whether model techniques would not be useful in meteorological research as well.

Hydraulic structures and/or the environment?∗

As implied by its title, the paper traces the development of an apparent conflict between technology and ecology, including aspects of population growth, resource availability, and waste. Practices of the Corps of Engineers and the Bureau of Reclamation are considered, and their culmination in passage of the National Environmental Policy Act with its emphasis on technology assessment. Attention is given to the fact that mans ability to produce changes in the environment continues to exceed his ability to predict the eventual results. It is concluded that technology and ecology are not inherently at odds; rather, because the social sciences lag far behind the physical and the biological, the difficulty lies wholly between us as human beings.

Air-Tunnel Studies of Diffusion in Urban Areas

The basic principles of model operation are outlined and the difficulties of general meteorological application described. Flow over a rough, irregular surface, such as an urban region, however, may be simulated in model studies: the experimental and analytical procedures for such studies are indicated. Finally, applications of the results of model tests to the pollution problems in urban areas are suggested.

Design Of Glass Panels For Hydraulic Flumes

The design of glass panels is described, with examples of flume depths up to 10 ft or 3 m for both annealed and tempered glass included. The following support conditions are considered: 1. Supports at top and bottom with vertical supports at the panel edges. 2. Supports at top and bottom, and also at the one-third point above the bottom, with vertical supports at the panel edges. Representative deflections are also computed.