Enterprise dynamic
To really make the soil-source heat pump can replace traditional air conditioning system, there are a large number of the core technical issues to be resolved. From the system's perspective, in the micro to the macro sequence has the following issues need to be addressed:
1, soil heat transfer and mass transfer processes of
in the bottom of the whole system are buried heat exchanger secondary subsystems. In the system, are the main concerns of the ground loop heat exchanger heat exchange with the surrounding soil. Due to soil is a by solid of soil skeleton, and liquid gas State water and air composition of more phase dispersed body, currently most of research in the used of simple of composite not steady-state thermal conductivity, will water and air of lost shipped process role due for a thermal conductivity coefficient of added value to description soil in the of hot quality coupled of practices apparently will brings larger of errors, corresponding of results soil source hot pump of buried to heat exchanger of size partial big, hot pump device of early investment increased (buried to heat exchanger of cost General accounted for to hot pump system total cost of 20%- 30%), unable to compete with conventional air conditioning systems.
urgent methods are buried heat exchanger heat exchange with the soil better mathematical model is used to describe the process, comprehensive consideration of the heat and mass transfer processes. Method of fluid mechanics in porous media can be a powerful tool. Researchers using an irreversible Thermodynamic approach to study is a highly innovative and feasible method. Researchers also made the use of fractal methods for study of thermal conductivity in the soil, has the potential to simplify the model, make research more difficult to reduce.
study on heat and mass transfer processes in the soil of another, is hoping to find heat transfer enhancement of new filling material, there are researchers engaged in this field of study abroad, and reports. Of course, the ultimate goal is the same, is to reduce as much as possible underground heat exchanger of ground-source heat pump of initial investment costs, but has yet to see a similar study reports.
2, study on coupled heat pumps and
study on coupled heat pumps and process aims to optimize performance of the heat pump system. By using soil as heat source, whether it is winter or summer, the operating conditions of the heat pump system (outdoor heat exchanger operating point) with traditional air heat pumps or water-source heat pump operating point has some differences, thus causing the whole characteristics of heat pump system with changes. Specifically, under the new outdoor heat temperature, how to configure corresponding evaporator, condenser, compressor and part of the whole system, heat pump thermodynamic cycle for optimal performance, maximize soil source heat pump energy-saving potential. Therefore, it is necessary to adopt the method of thermal dynamics of refrigeration system.
3, ground-source heat pump system economic analysis of annual energy consumption of
from the ground source heat pump heating system diagram, you can see that the problem is the third level of analysis of annual energy consumption of the entire heat pump system. For situations that require year-round air conditioning, using ground-source heat pumps have the advantage of conclusions should be based on annual energy consumption analysis of the results obtained.
This is especially important in determining when ground-source heat pump. For different meteorological conditions and different functional requirements of buildings, cooling and heating load in winter and summer and two buildings may not be the same. Priority should be given to winter heating, summer gap by conventional air conditioning system cooling load (such as installing cooling towers) supplement; or in the cooling load in summer as a benchmark, using an auxiliary heat source in winter mode? Should be based on annual energy consumption analysis, comprehensive consideration of the system of investment and running costs, and ultimately to payback period used as a basis for.
only in the underground heat exchanger of heat transfer process and dynamic thermal characteristics of heat pump system with a complete knowledge and understanding on the basis of combined with annual dynamic load of a building in order to make full play of the advantages of ground source heat pumps, energy-saving and environmental protection objectives.