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The 90th Anniversary of the Fluids Engineering Division (FED) of ASME will be celebrated on July 10–14, 2016 in Washington, DC. The venue is ASME's Summer Heat Transfer Conference (SHTC), Fluids Engineering Division Summer Meeting (FEDSM), and International Conference on Nanochannels and Microchannels (ICNMM). The occasion is an opportune time to celebrate and reflect on the origin of FED and its predecessor—the Hydraulic Division (HYD), which existed from 1926–1963. Therefore, the FED Executive Committee decided that it would be appropriate to publish concurrently a history of the HYD/FED. Accordingly, they commissioned Paul Cooper, C. Samuel Martin, and Timothy O'Hern to prepare this paper, which would document the division's past. A brief work in this direction had appeared in the 2010 FED Newsletter (Morgan, W. B., 2010, Brief History of ASME's Hydraulic/Fluids Engineering Division, Fluids Engineering Division Newsletter, New York, pp. 6–7), and the research by Martin for the present paper had been under way for several years prior to that (Cooper, P., 2010, “History of the FED,” FED Executive Committee at the ASME-CSME Fluids Engineering Summer Conference (FEDSM-2010), Montréal, QC, Canada, Aug., p. 14).

Careful experiments have been conducted for the purpose of investigating the phenomenon of condensation-induced waterhammer in an ammonia refrigeration system. To initiate a waterhammer event warm ammonia gas was introduced over static subcooled ammonia liquid placed in a horizontal 146.3 mm diameter carbon steel pipe 6.0 m in length. By means of fast response piezoelectric pressure transducers and a high speed data acquisition system rapid dynamic pressures were recorded whenever a shock event occurred. The occurrence of condensation-induced waterhammer depended upon three major variables; namely, (1) initial liquid depth, (2) liquid temperature, and (3) mass flow rate of warm gas. For given liquid depth and temperature, once the warm gas threshold conditions were exceeded shocks occurred with greater magnitude as the mass flow rate of gas input was increased. With adequate subcooling condensation-induced waterhammer occurred for initial liquid depths ranging from 25% to 95% of internal pipe diameter. The threshold mass flow rate of warm gas necessary to initiate waterhammer was greater as the initial liquid was lowered.Copyright © 2003 by ASME

Two methods of analysis of surges in power canals, namely the graphical method of Bergeron and a finite-difference method based on the partial differential equations of motion, are applied to a surging situation of an engineering project for which laboratory model test results are available. For short power canals for which the effects of friction are small and the effect of gravity and inertial are significant a comparison of the results of the simple graphical method, for which bottom slope, boundary friction and finite-amplitude effects are neglected, with those of a finite-difference method, for which these effects are included, indicate that the graphical method of analysis is quite adequate for analyses of surging in short power canals.

The effective seepage force on cohesionless interfacial bed particles that comprise a plane bed was determined from the results of slope instability tests and from extrapolation of the results of erosion tests. The seepage flow was perpendicular to the bed and either into or out of the bed for the slope instability tests. Tests were conducted using two columns, one square and the other circular, in cross-section. For uniform sand particles ranging from 0.46 mm diam. to 0.72 mm diam., the seepage force on the interfacial sand grains was determined from slope instability tests to be one-half that on particles well within the bed. Subsequent to the condition of instability for seepage flow vertically upward and into a bed, erosion of the sand bed was measured. From an extrapolation of the results of the erosion tests to a condition of no erosion (which was assumed to correspond to the condition of incipient instability), it is concluded that the seepage force on the interfacial grains is approximately 35% to 40% of that on grains well within the bed.

THE EQUATIONS OF MOTION FOR UNSTEADY GRADUALLY-VARIED FLOW IN OPEN CHANNELS ARE EXPRESSED IN A FINITE-DIFFERENCE FORM SUITABLE FOR PROGRAMMING ON A HIGH-SPEED DIGITAL COMPUTER. THE STAGGERED-NET SCHEME INTRODUCED BY STOKER IS EXPANDED TO BE APPLICABLE TO A SYSTEM OF INTERCONNECTED CHANNELS, WITH EACH OF THEIR ENDS SUBJECT TO ONE OF THE FOLLOWING BOUNDARY CONDITIONS: DISCHARGE HYDROGRAPH, STAGE HYDROGRAPH, STAGE-DISCHARGE RELATIONSHIP, DEAD END OR JUNCTION OF CHANNELS. THE THEORY AND COMPUTER PROGRAM ARE TESTED AND COMPARED WITH EXISTING EXPERIMENTAL RESULTS CORRESPONDING TO THE FOLLOWING SITUATIONS: (1) FLOOD HYDROGRAPH IN CIRCULAR CHANNEL, (2) POWER-LOAD REJECTION IN HEADRACE OF TRAPEZOIDAL CANAL, (3) POWER-LOAD ACCEPTANCE IN TAILRACE OF RECTANGULAR MODEL CHANNEL, AND (4) TIDAL (STAGE HYDROGRAPH) IN RECTANGULAR MODEL ESTUARY. BECAUSE OF GOOD CORRELATION BETWEEN SIMULATED AND EXPERIMENTAL RESULTS IN ALL FOUR INSTANCES AND THE EASE OF CODING VARIOUS PROBLEMS, THE STAGGERED SCHEME OF STOKER IS STRONGLY RECOMMENDED FOR PRACTICING ENGINEERS. /ASCE/