Study of the Effect of a Cooling Load on a Fluid Surface (Water) in an Open Channel

Document Type : Regular Article


International Hellenic University, Department of Environmental Engineering, Sindos, 57400, Thessaloniki, Greece



In this study the effect of cooling load on the surface water of an open channel with different flow depths is investigated. The method, which was used, involves an experimental laboratory set-up that contains a well-insulated cooling load over a finite area of the water surface, without direct contact with the free water surface so that losses of load to the environment should be avoided. The different cooling loads for each experiment were achieved with the use of insulating films. The insulating film is placed at the bottom of the experimental set-up where there was an empty surface (gap - D), through which the cooling load is allowed to pass. The measurement of velocities was carried out at a two-dimensional (XZ) field, with the help of a digital camera. The recording of motion of the dye (rhodamine) along the channel per unit of time, allows the calculation of the values of the velocity fields. Measurements were conducted when the phenomenon becomes steady. The results for the determination of the cold mass length as a function of the flow depth, and the temperature difference ΔT, in a state of thermal equilibrium, led to the formation of a new mathematical relationship. Further study of the phenomenon is essential for the improvement of this study, in combination with other parameters that affect the aquatic ecosystem.


Main Subjects

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