Study On The Influence Of Pump Combination On The Stability Of Air Conditioning Water System

With the increasingly high demand for energy-saving and the indoor environ ment, air conditioning and heating system is applied more and more widely, for the stab le operation of the system also has the more intense. Improve the system stability, not only for energy conservation have extraordinary significance. The quality of heating and air conditioning, and extend the service life of the equipment has important significanc e. How to choose the best combination of the water pump, which makes system stability b etter, this is the main research content of this article. Change the mode of combination of the water pump has a certain influence on the stability of the system.Introduced 1 matching problem of pump and pipe network, using the H-Q diagramexpl ains the power unit working state in the pipe network in point. Study on water system, ref erring to the network of fluid network computing method, elaborated the hydraulic imbala nce and sensitivity of the system stability analysis method.Air conditioning chilled water system and cooling water system for the engineering c ase, selection of single, two of the same type, the three sets of the same types of pum ps in parallel the three combinations, the use of MATLAB software and pump performan ce curves of the three kinds of combination fitting, it is concluded that the two cases n ot with pump combined operation system of the total flow, further calculates the hydrauli c loss of scheduling. The main conclusions are: in cooling water system, three sets of t he same types of parallel pumps this kind of combination of the system stability of the minimum, and in the cooling water system in a single pump operation of system stabilit y with minimal impact.For the same process and different process system, in a ten branch system, selecti on of single, two sets of the same type, two sets of the different models, three with typ es of pumps in parallel the four combinations, turn off the branch, a plurality of branche s, the network is solved, calculation of other branches of the hydraulic imbalance degre e method, analysis of the impact on the stability of the pump combination. The main co nclusions are: 1) different regulation system, with farther and farther away from the cold and heat sources, branch of the hydraulic disorder degree gradually increase can be s ummarized as: closer to the cold and heat sources, better the stability of the slip road. On the contrary, the stability of the slip road worse. Close the branch number, branch of t he hydraulic imbalance is bigger, and the greater the increase in the degree of hydraulic misadjustment. Close all branches of cold and heat source has little effect on the other branch. On the contrary, shut away from the branches of cold and heat source of other branch has the effect can not be ignored. 2) system, stability has obvious symmetry an d stability in the middle of the line is the worst, the pipeline at both ends of the best st ability.Using the stability sensitivity on the same way and different regulation system to quan tify theevaluation and comparison. Main conclusions: select the same process system, m ake it easier for the pipe network hydraulic balance, but with the way the system stabilit y in general different regulation system than to poor, this is because when the minimum impedance branches with the way the system with different process system is equal, t he smaller the total impedance of the network, which will lead to pipe network character istic curve and the pump characteristic curve of the intersection from the design operati ng point, rather than closer to the design operating point.By theoretical analysis and practical calculations show that using different combination s of pumps, the stability of the system is different. For the whole network system, in the cooling water system, three sets of the same types of pumps in parallel, the stability of the system is the best, in the cooling water system, a single pump operation, the stabi lity of the system is the best, the due to the selection of pump, in the two pump combi nations, pump the actual working point closest to the design operating point. When multi ple branch impedance may change, the choice of different types of combinations of pu mp will increase the stability of the system. The conclusion and correct choice has certain guiding significance to the water pump.