Forecasting Hourly Sewage Quantity And Optimization Design Of Heat Pump System

With the successful completion of energy-efficient buildings "11th Five-Year Plan", our country has stepped to a new pace in the construction of building energy efficiency. In order to keep up with the trend of " 12 th Five-Year Plan", research in sewage source heat pump applications gradually increasing, the using of sewage waste heat as a way to extract renewable energy,compared with conventional air conditioning methods, it has notable features in green energy and economic.Based on the project example in Wuhan, the definition and operating principle of heat pump are introduced firstly, then put more attention on the extrinsic parameters such as sewage temperature, water flow. The result of annual hourly dynamic load calculation by DeST is favorable to the analysis of the annual hourly load’s characteristics. The load characteristics provide guidance basis for the choice of air conditioning system forms and cold and heat source scheme. In order to demonstrate the reasonableness of the unit selected,the essay establishes personalization engineering models of 30 HXY water-cooled screw chillers which are used to describe the nonlinear function relationship between chiller’s property parameters(cooling capacity, power consumption and COP) and 4 external parameters(outlet temperature of cooling water, inlet temperature of chilled water, cooling water flow and chilled water flow) according to multi-parameter nonlinear function expression between chiller’s external parameters by MATLAB. By the relative error test, the model has high accuracy, in line with the actual engineering requirement, can be reliably used in the simulation of air-conditioning systems. Combined nonlinear function model,forecasting hourly sewage quantity of heat pump whole year, and propose solutions in condition of the limit of flow rate.In order to match cooling capacity of building needs better, it can adjust their actual loads to meet the operate of heat pump. About the sewage source heat pump operating under part load, it can be optimized choose the best switching point to respond to the load changes.Taking the type 30HXC500 AH screw chillers for example, according to the total energy consumption in different switching point, find the 50% of total cooling load is optimum switching point, which is the most optimization control scheme of the unit.