LEAN

UNITED KINGDOM (see also List of Individuals)

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28.1.1915 Portsmouth/UK - 3.2.1997 Reading/UK

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George H. Lean joined the Scientific Civil Service as an established officer after World War II and began work at the National Physical Laboratory, where the newly founded Hydraulics Research Organization HRO found its feet. He moved in 1949 with the Hydraulic Research Station HRS to Wallingford and there remained until his retirement in the late 1970s. Lean started as a scientific officer, was promoted to senior scientific officer and finally to principal officer. He was a bright man with an enquiring mind, but shy and disinclined to push himself forward. He was happiest working away on his own in a laboratory on mainly basic research.

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Lean worked on a number of hydraulic problems mainly relating to open channel flow. These include the hydrodynamic forces on hydraulic structures, an alternative method of sediment transport determination, density currents due to a warm water jet, the accretion characteristics upstream of a weir and wave propagation in a rectangular channel. The latter study involved a steady discharge with a steadily rising or falling water level at the downstream channel end. With a rising tailwater level a bore forms for supercritical flow in the approach flow channel. With a falling tailwater level corresponding to an ebb tide, a wave traveling downstream at constant velocity disappears if the rate of level fall exceeds the velocity of a kinematic wave. When this happens the wave accelerates downstream and the wave form gradually flattens.

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_{Anonymous (1955). Participant George H. Lean. 6 IAHR Congress La Haye 1: Frontispiece. P}

_{Crickmore, M.J., Lean, G.H. (1962). The measurement of sand transport by the time-integration method with radioactive tracers. Proc. Royal Society 270: 27-47.}

_{Lean, G.H. (1955). The forces on a horizontally pivoted butterfly weir. 6 IAHR Congress The Hague C(3): 1-17.}

_{Lean, G.H., Whillock, A.F. (1965). The behaviour of a warm layer flowing over still water. 11 IAHR Congress Leningrad 2(9): 1-12.}

_{Lean, G.H. (1965). A particular case of steady wave propagation along a parallel-sided open channel. Journal of Hydraulic Research 3(1): 31-41.}

_{Lean, G.H. (1965). Accretion upstream of a weir. Civil Engineering and Public Works Review}

_{60(1): 83-86.}

_{Lean, G.H., Price, W.A. (1977). The effect of passing vessels on a moored ship. Dock and Harbour Authority 58(11): 275-277.}

_{Lean, J. (2007). George Lean. Personal communication. P}