Estimating flow discharge for selected passages in Mammoth Caves based on analysis of scallop lengths and passage areas
Loading...
Date
2008-12
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
The Ohio State University
Abstract
The purpose of this study is to estimate the flow discharge for select cave passages in the Mammoth Cave System. This is done in two steps. First, peak flow velocity is calculated using scallop length measurements and a graph based on the equations of Curl (1974), which yield the average flow velocity of a rectangular or circular passage. Next, a cross section of the specific cave passage is measured using a laser distancemeter and a measuring tape. From these measurements, the cross-sectional area of a cave passage can be calculated. These data can then be combined with the flow velocity data to estimate the peak flow discharge of the cave passage. Mean scallop lengths range from 10 to 72 cm. Passage areas range from 13 to 590 ft². Estimates of mean discharge range from 12 to 649 ft³/sec. Analysis of these data shows that passage areas decrease downstream, suggesting a similarity to a distributary channel system. Data also suggest that as passage area decreases, mean water velocity increases. To eliminate sampling bias from too few measurements, it is suggested more data be collected.