Role of Hydraulics and Fluid Mechanics in Environmental Engineering Publications

This Journal deals with a great number of issues associated with assessing and controlling water and air quality. Accurately describing the movement of air and water is sometimes critical to the applicability of the concepts and methods presented. There are probably few readers of this Journal who would argue with the previous statement; however, some might argue that a paper with a focus on the hydraulics and fluid mechanics of an environmental problem is misplaced. For example, proper description of the flow in manifold distribution systems in water and wastewater treatment plants is important in the effective operation of the plants, but the manifolds have no direct effect on water quality. Therefore, it could be argued that a paper on that topic submitted to the Journal of Environmental Engineering (JEE) should more appropriately appear in ASCE's Journal of Hydraulic Engineering (JHE). Yet, throughout the years, there have been several papers on the topic appearing in this Journal. Through recent decades, papers have appeared whose conclusions are critically dependent upon computational fluid mechanics (CFD) models. The accuracy and appropriateness of the models is seldom questioned. This is probably the wrong venue for critical analysis of fundamental fluid mechanics principles, but in some instances, assurance of the reliability of results demands it. Based on my recent reading of JEE, I had the impression that fluid mechanics related topics had not received an undue amount of coverage, but I had not tried to critically analyze the coverage. What follows is my attempt to quantify and analyze the portion of publication focus directed toward topics dependent upon fluid mechanics or hydraulics in this Journal and in another somewhat overlapping journal that should have a substantial interest in the topic (Journal of the American Water Works Association, JAWWA).

Analysis of content will begin with the January 2003 through October 2005 issues. Content that utilizes assumed flow distributions, hydrologic analysis, and non-physically based flow routing have been excluded. Beginning with JEE, papers with significant hydraulics or fluid mechanics content are summarized in Table 1. Out of the 26 papers judged to have significant hydraulic or fluid mechanics content, I judge that six have weak or no connection to transport of dissolved or suspended contaminants. Considering that approximately 400 papers were published during that period, there does not seem to be an undue emphasis. I would suspect that if the six papers I cited had been originally submitted to JHE, that Journal might have considered redirecting the paper to JEE. In an ideal world, the reviewers of these papers would come from the readership of the Journal. In practice, this is not always the case, and reviewers selected from the JEE reviewer database sometime express a reluctance to comment on aspects of the papers that they consider to be purely of a fluid mechanics or hydraulics nature.

The breadth of appropriate topics for JEE, even within this limited subtopic, is impressive. When I evaluate the papers in Table 1 for overlap with publication interest in JAWWA, I conclude that only eight could even remotely be considered as candidate topics in both journals. I would judge that the purely engineering focus of JEE is the primary reason for the lack of substantial overlap, but readers should bear in mind that I am considering a narrow area of overlap.

A listing of papers related to hydraulics and fluid mechanics appearing in JAWWA during the study period is shown in Table 2. While the total number is about one-fourth of those in JEE, the total number of papers appearing during the study period is one-third of those in JEE. All of the topics covered would fit within the scope of JEE or JHE, but I judge that only the three papers on storage tank mixing and disinfection would be most appropriately directed to JEE. There seems to be little overlap in publication within the hydraulics and fluid mechanics subarea between JEE and JAWWA. Whether this should be judged to be good or bad I leave to others, but my personal wish is that there would be more papers in this area in both journals.

In summary, I feel that based on recently published papers in this Journal, the emphasis on hydraulics and fluid mechanics is appropriate and provides timely and relevant content. As a side note, I received an extra benefit from sifting through these publications. In searching for hydraulics and fluid mechanics content I was reminded of the breadth of our discipline. I encourage all readers to take a deeper look at the papers in this Journal, not just within your strict area of expertise, but with an educational purpose. I think that reading this Journal should qualify for continuing education credits, but that is a topic for a different editorial.