1、OR-05-2-3 Pressure Loss Coefficient Measurements of Two Close-Coupled HVAC Elbows Nanda Kishore Mylaram Stephen Idem, PhD Member ASHRAE ABSTRACT An experimentalprogram was initiated to determine the friction factor in a straight duct and the loss coeficient of either a single elbow or two elbows pla
2、ced in close proximi The tests were performed in accordance with ANSUASHRAE Standard 120-1999. Loss coeficients C were measured for six kinds of single elbows. Likewise, identical pairs of elbows were considered in the close-coupledelbow experiments. For long separation lengths, the loss coeficientf
3、or two close-coupledelbows approached to within approximately 10% of the value of 2*C for a single elbow, for most cases considered in this study. The single-elbow data were also compared with thosepublished in the 2002 ASHRAE Duct Fitting Database. *The full text of this paper can be found in the I
4、nternational Journal ofHeating, Ventilating, Air-conditioning and Refrigerating Research, Volume 11, Number 1, January 2005, pp. 133-146. Responses to questions/comments to this paper will be published in the Research Journal. Nanda Kishore Mylaram is a research assistant and Stephen Idem is a professor of mechanical engineering at Tennessee Technological University, Cookeville, Tennessee. 02005 ASHRAE. 521
