Thermal Stratification of Seymareh Dam Using Two-Dimensional, Hydrodynamic and Water Quality Model: CE-QUAL-W2

 Thermal stratification in the reservoir changes the physical, chemical and biological quality at different levels. Temperature conditions of the reservoirs can be predicted using mathematical models. CE-QUAL-W2 is a two-dimensional, hydrodynamic and water quality model that is used for thermal stratification regarding its capabilities.

 CE-QUAL-W2 is used for thermal stratification in Seymareh dam. Calibration is first step in modeling. Calibration is an iterative process whereby model coefficients are adjusted until an adequate fit of observed versus predicted data is obtained. CE-QUAL-W2 model has three calibrations phase including volume-elevation, water balance and thermal calibrations, all have done for model optimum performance. After the calibration, stratification results are extracted for the various months.

 The root mean square error of calibration calculated by comparing the actual data and the observed data were 0.5, 0.05 and 1.62, respectively, indicating that the model for the layer Thermal conditioning is suitable. This stratification continues from March to December and culminates in autumn. The thickness of the surface layer of water, called the roller, varies from month to month. This difference is also seen in the middle layer or the thermocline in different months. The thickness of roller in December is more than other months.

 Based on modeling information, it has been determined that the Seymareh Dam has a thermal stratification period. The presence of this layering in the reservoirs causes the organic matter and sedimentation of sediments to gradually increase in the bottom of the reservoir.