The crucial and most susceptible component in integrated energy system is the district heating system. The flow-regulation mode, compared with temperature-regulation mode, has better equipment operation conditions. But so far, there has been no a hydro-thermodynamic dynamic coupling model in terms of flow-regulation model in district heating system. This research proposes a precise model that considers the coupled dynamic hydraulics and dynamic thermodynamics in district heating system. The modified forward-backward iteration, which uses method of characteristic for hydraulic calculation and upwind difference for thermal calculation, is applied to model computation. To do quick calculations, a hybrid prediction model based on data-driven methodology is used, considering the tradeoff between accuracy and efficiency. Two cases with four situations each are utilized in the case study to certify the effectiveness of the suggested methodology.