An experimental study of salt wedges

Originally issued as Reference No. 51-99, series later renamed WHOI-.The objective of the estuary studies being conducted at this Institution is to attempt an understanding of tidal flushing. Two theories have been developed, that of Ketchum employing an extension of the tidal prism technique, and that of Arons and Stommel who treat the flushing problem through the diffusion theory. An experimental program has been established to determine the validity of these theories so that model laws may be established for tidal flushing. At the beginning of this program, the phenomenon of the salt water wedge was observed in the experimental apparatus over a wide range of flow conditions. To produce salinity distributions other than this, it was necessary to stimulate diffusion of the salt water with turbulence created by added roughness. In view of the apparent importance of the salt wedge, it was decided that an investigation of the factors that influence its shape and length would be of particular value to the future work. An empirical equation has been developed which describes the salt water wedges formed in the laboratory. This equation, how ever, does not describe well the salt wedge as found in the Mississippi River. It is of particular interest that the equation appears to describe the mean horizontal distribution of salinity in estuaries where the fresh and salt water are well mixed and not stratified as in the wedge.Office of Naval Research under Contract No. N6onr-27701 (NR-083-OO4

Burst avalanches in solvable models of fibrous materials

We review limiting models for fracture in bundles of fibers, with statistically distributed thresholds for breakdown of individual fibers. During the breakdown process, avalanches consisting of simultaneous rupture of several fibers occur, and the distribution $D(\Delta)$ of the magnitude $\Delta$ of such avalanches is the central characteristics in our analysis. For a bundle of parallel fibers two limiting models of load sharing are studied and contrasted: the global model in which the load carried by a bursting fiber is equally distributed among the surviving members, and the local model in which the nearest surviving neighbors take up the load. For the global model we investigate in particular the conditions on the threshold distribution which would lead to anomalous behavior, i.e. deviations from the asymptotics $D(\Delta) \sim \Delta^{-5/2}$, known to be the generic behavior. For the local model no universal power-law asymptotics exists, but we show for a particular threshold distribution how the avalanche distribution can nevertheless be explicitly calculated in the large-bundle limit.Comment: 28 pages, RevTeX, 3 Postscript figure

Classic Article: Control of salinity in an estuary by a transition

A theoretical reason is developed to explain why the mouth of a vertically stratified estuary should act as a constraint on the amount of salt water available for mixing in the estuary. Flume experiments designed to test this idea are described. The effect of tides on the control action and application to various estuaries is discussed

Abrupt change in width in two-layer open channel flow

An abrupt widening in a channel can act as a control on the regime of two-layer flow immediately upstream. A simple explanation in terms of an interfacial Froude number is offered and a set of experimental verifications is described. Bernoulli\u27s Principle is applied to an abrupt narrowing

Control of salinity in an estuary by a transition

A theoretical reason is developed to explain why the mouth of a vertically stratified estuary should act as a constraint on the amount of salt water available for mixing in the estuary. Flume experiments designed to test this idea are described. The effect of tides on the control action and application to various estuaries is discussed

Hanford Single-Shell Tank Leak Causes and Locations - 241-A Farm

This document identifies 241-A Tank Farm (A Farm) leak causes and locations for the 100 series leaking tanks (241-A-104 and 241-A-105) identified in RPP-ENV-37956, Hanford A and AX Farm Leak Assessment Report. This document satisfies the A Farm portion of the target (T04) in the Hanford Federal Facility Agreement and Consent Order milestone M-045-91F

A survey to test the story book knowledge of kindergarten children.

Thesis (Ed.M.)--Boston Universit

On the nature of estuarine circulation : part I (chapters 3 and 4)

The reader will quickly see that the subject matter of Chapter 3 is confined to the hydraulics of sharply stratified media, whereas real estuaries are always more or less diffusely stratified. What is more, no discussion is made of the order of magnitude of the friction terms. In ordinary single layer flow (such as in rivers) engineers already have crude approximations of the friction terms (Chezy and Manning formulas), but we do not have even these approximations for two layer flow. For this reason the differential equations of gradually varied flow of two layers are for the most part left unintegrated and all that is demonstrated is the qualitative aspects of the flow. In the case of entrainment of water from one layer into another we can only perform integrations of the equations when the amount of entrainment is known, whereas in real estuaries we do not have a priori knowledge of this amount. The reader will see, therefore, that the subject matter of Chapter 3 is really very incomplete, leaving undetermined all the constants which depend upon turbulent mixing, upon the frictional stresses on the bottom, and the free surface and the walls, and upon the amount of entrainment. The contents of Chapter 4 are somewhat different. First of all, they contain summaries of several of these papers have proceeded on the basis of hypotheses already published papers on the mixing in estuaries. Most about the nature of the mixing process. The applicability of these hypotheses appears to be restricted to only certain estuaries, and it must be admitted that more work has been done that involves guessing what the mixing processes in an estuary might be, than has been done in trying to find out what the mixing processes in an estuary actually are. As incomplete as the subject matter of Chapter 4 is, it is hoped that it will suggest which of the possible mixing processes in estuaries may be important in any particular one which is the subject of study, and that it will also suggest the type of observations which will be most desirable in studying a particular estuary. For example: in an unstratified estuary it seems that a more or less uniform spacing of stations up and down the estuary is desirable; but in an estuary which appears to be subject to the constraint of overmixing (Section 4.51) the location of stations should be largely confined to control sections.Office of Naval Research under Contract No. N6onr-27701 (NR-083-004)