The Effect Of Hydraulic Balance Device’s Performance On Hydraulic Stability In Heat Metering System

Implementation of heat metering is one of the most important measures onreducing heating energy consumption and realizing energy saving of user behavior.As we know heat metering is focused on adjustability and operation, whichdetermines that the importance of thermostatic radiator valve and hydraulic balancingdevice becomes more remarkable in heating system.In the present paper，the relationship between thermostatic radiator valve’sperformance and its authority was analysed. The results show that valve’s ability ofregulation is closely related to its authority. With the decrease of the thermostaticradiator valve’s authority, the characteristic between the heating and valve stem’s liftgradually deviates from linear characteristic farther, and the proportion of non-linearcontrol hours gradually increases throughout the heating period. To insuer95%of theheating period is under linear control, the thermostatic radiator valve’s authority cannot be smaller than0.15.The related data of a residential area in Tianjin was investigated and testedduring the heating period. By comparing the investigated data and computational data,it can be found that the feasibility of theoretical method to calculate the hydraulicstability is high. From the computational results, it is shown that the applicability ofstatic state balance valve is mainly related to the authority and maximum permissiblepressure drop of thermostat radiator valve, and the constant differential pressurecontrol mode. Applicable pressure drop of pipe network is not more than9.2kPa and14.6kPa in proximal and distal constant differential pressure control respectively, andapplicable heating radius is not more than59m and94m respectively. Applicabilityof self-operated pressure differential control valve is mainly related to the authorityand the maximum permissible pressure drop of thermostat radiator valve, and themaximum permissible pressure drop of self-operated pressure differential controlvalve. Applicable pressure drop of pipe network is not more than248kPa in proximaland distal constant differential pressure control, and applicable heating radius is notmore than1590m. When the pipe network has multiple branches, multiple collectionpoints need to be set to make sure distal pressure valve in distal constant differentialpressure control, in order to the stability of the hydraulic system.