Buried Pipe Hydraulic Balance And Optimization Of Ground Source Heat Pump System

Ground source heat pump system compared with the traditional air-source heat pump system, the biggest difference is that the different forms of the heat exchanger. Ground source heat pump system buried the U-tube heat exchange in the soil to achieve the purpose of regulating buildings’air condition. So the heat exchanger performance and operating results running an important impact on the system. In recent years, academic research is focused on how to strengthen the ground heat exchanger performance, and reducing heat transfer effects between pipes. There was less research on fluid flow characteristics and pipe hydraulic balance. Particularly, there was no research on the impact of hydraulic imbalance between the tube group to the entire system running. Up to now there was not forming a complete system to evaluate the underground pipe system operating characteristics and energy saving.This paper introduces the heat transfer model used in the ground heat exchanger. The heat transfer of ground heat exchanger divided into the heat transfer within the drilling and drilling in the outer. The inner heat transfer model is divided into one-dimensional, the two-dimensional, and the quasi-three-dimensional heat transfer model. The outer heat transfer is divided into one-dimensional heat conduction model and limited long-term heat source model. Choosing the quasi-three-dimensional model and cylindrical surface of the one-dimensional model to form ground pipe heat model and design its length.Under the premise of pipe length has been determined, according to the principle of hvdrodynamic to determine the calculation method of the svstem resistance. To calculate the partition system resistance to determine the resistance unbalance ratio between the partition system. Using matlab language compiled optimization software.According to this software, we can get each partition system resistance, transport energy-efficiency and the recommended pump head and flow. Different target can get different optimization design.