Systematic pilot experiments were performed under an average temperature gradient of 0.37℃/cm over the thermocline in a stratified reservoir model. The process of inducing internal waves by aeration was analyzed, the types of aeration-induced internal waves were explored, and the effects of disturbing source from aeration and the thickness of the thermocline on the generation and characteristics of internal waves were mainly investigated. The air-water two-phase flow generated from the water-lifting aeration was a kind of unsteady periodic disturbing source, the water in the reservoir model was driven to oscillate up and down by the air-water two-phase flow, and the internal waves were then induced by this oscillation in the stratified fluid. From the point of inducing source, the aeration-induced internal wave can be classified into a kind of wake-generated internal wave. The amplitude of internal waves peaked when the releasing periods of air piston were within the range of 44.06~58.69s. The internal waves were unable to be induced continuously when the releasing periods of air piston were longer than 180s. The amplitudes and periods of internal waves tended to increase with the diameter of the outlet of the water-lifting aerator. The generation of internal waves was also influenced by the thickness of the thermocline. Under constant temperature gradient, the amplitudes and periods of internal waves tended to increase with the thickness of the thermocline.
孙昕, 杨潘, 解岳. 分层水环境曝气诱导形成内波的过程与特性[J]. 中国环境科学, 2016, 36(9): 2658-2664.
SUN Xin, YANG Pan, XIE Yue. Process and characteristics of aeration-induced internal waves in stratified water environments. CHINA ENVIRONMENTAL SCIENCECE, 2016, 36(9): 2658-2664.
Jason H, Lars U. Modelling the tidal mixing fronts and seasonal stratification of the Northwest European Continental shelf[J]. Continental Shelf Researeh, 2008,28:887-903.
Sun X, Li X L, Zhang M D, et al. Comparison of water-lifting aerator type for algae inhibition in stratified source water reservoirs[J]. Ecological Engineering, 2014,73(12):624-634.
[19]
Cong H B, Huang T L, Chai B B. Water-circulating aerator: optimizing structure and predicting water flow rate and oxygen transfer[J]. Journal of Hydraulic Engineering, 2011,137(6):659-667.
[20]
Knoblauch H, Klasinc R, Geisler T, et al. Application of an Ultrasonic Velocity Profile Monitor in a Hydraulic Laboratory[J]. American Society of Civil Engineers, 2014(2002):1-10.
[21]
Takeda Y. Velocity Profile Measurement By Ultrasonic Doppler Method[J]. Experimental Thermal & Fluid Science, 1995,10(4): 444-453.
Diamessis P J, Wunsch S, Delwiche I, et al. Nonlinear generation of harmonics through the interaction of an internal wave beam with a model oceanic pycnocline[J]. Dynamics of Atmospheres & Oceans, 2014,66(2):110-137.
[30]
Cheng M H, Hsu R C. Effects of varying pycnocline thickness on interfacial wave generation and propagation[J]. Ocean Engineering, 2014,88(4):34-45.