VI -231 



RECOMMENDATIONS CONCERNING 

 PHYSICAL PROCESSES AND INTERATIONS 



Initial Dilution and Diffuser Design 



(1) Present knowledge of buoyant jet diffusion is nearly 

 adequate for design of an outfall (including a multiple- 

 port diffuser) to achieve a prescribed initial jet dilution 

 and submergence below any given thermocline. However, 

 further research is needed in a number of areas. Primarily, 

 there is need for understanding of line sources, and how 

 well multiple- jet diff users may be represented by line 

 sources. Although current effects on initial plume 

 behavior are not well understood, they are not as critical 

 as density stratification as a factor in predicting initial 

 dilutions due to jet mixing. 



(2) Methods do not exist for predicting the size and shape 

 of waste fields (of either conventional or heated effluents) 

 which are developed at the end of the initial jet-mixing 

 stage. Closely coupled with this is the problem of lateral 

 spreading due to density differences between the field and 

 its environment. Research should be conducted on both of 

 these problems. 



(3) For barge dumping of sludges in the ocean, research is 

 needed on flows generated by suddenly released sinking sludge 

 in a stratified environment. 



