Document: NRC Regulatory Guide
Document ID: f4c5fb1d-efb9-4168-9804-5ad3f6f64d06
Document Type: regulatory_guide
Title: Reporting Procedure for Mathematical Models Selected To Predict Heated Effluent Dispersion in Natural Water Bodies
Source: NRC Regulatory Guide Division 4
Source URL: https://www.nrc.gov/docs/ML0037/ML003739535.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-4.4
CFR Part: 
CFR Title: 

Content:
nce from the discharge point, the magnitude of which depends upon the ratio of discharge velocity to ambient velocity, the motion of the effluent completely follows that of the ambient current. If the initial velocity ratio is less than about 10, cross-flow effects on the discharge jet are significant in the near-field." Ambient current motion around the discharge jet creates a pressure drag analogous to that induced on a solid object inserted into a uniform flow field. A fraction of initial discharge momentum is expended to maintain the integrity of the jet in response to the external pressure field. If the initial velocity ratio is below 2, pressure drag effects on the discharge jet by the ambient current can become important.5 3 R. A. Paddock, A. J. Policastro, A. A. Frigo, D. E. Frye, and J. V. Tokar, "Temperature and Velocity Measurements and Predictive Model Comparisons in the Near-Field Region of Surface Thermal Discharges," Center for Environmental Studies, Argonne National Laboratory, ANLUES-25, 1973. 4 .L H. Carter, "A Preliminary Report on the Characteristics of a Heated Jet Discharged Horizontally into a Transverse Cu-rent; Part I-Constant Depth," Chesapeake Bay Institute Technical Report No. 61, November 1969. 5B. A. Benedict, J. L. Anderson, and E. L. Yandell, "Analytical Modeling of Thermal Discharges: A Review of the State of the Art," Center for Environmental Studies, Argonne National Laboratory, ANL/ES-1 8, 1974. 4.4-7 In the case of a shallow-water, nearshore jet in which the discharge extends from the water surface to the bottom, entrainment is effectively confined to the upstream, offshore side of the jet. On the nearshore side in the downstream direction, the quantity of ambient dilution water can be severely limited, and recirculatlon ()f partially diluted effluent becomes a definite possibility. The situation is less serious for a discharge in deep water. In this case, ambient water can move under as well as around the jet; pressure drag is