Research On Heat Station Resistance Based On The Flow Distribution Of Plate Heat Exchanger

In a centralized heating system,a heating station serves as a hub connecting the primary side and the secondary side,which largely determines the heating effect of the heating users and the energy consumption of the entire system.The plate heat exchanger as an indispensable equipment in the heating station directly determines the temperature of the supply and return water on the secondary side,and it is also the device with the largest flow resistance in the heating station.In many heating systems with poor thermal performance,there is a phenomenon that the heat resistance of the plate heat exchanger is too large,resulting in excessive pressure difference in the heat station,increased power consumption of the circulating pump,and poor thermal station operation.Therefore,analyzing the flow resistance of the board-changing part and taking measures to reduce the resistance of the board-changing part is of great significance for the economic operation of the system.Based on the flow characteristics in the plate heat exchanger,this paper analyzes the flow distribution among the flow channels in the plate heat exchanger and builds a calculation model for the resistance of the plate heat exchanger based on this.It is solved by numerical methods.The results show that due to the resistance at the corner hole,the flow rate between the flow channels in the plate heat exchanger is not consistent,and the flow rate in the plate change channel decreases with the increase in the number of flow channels.Based on the plate heat exchanger resistance calculation model,the resistance of a certain type of plate exchange under different angles of holes,number of sheets,and flow rate was calculated,and the influence of these three factors on the resistance of the plate heat exchanger was analyzed.The results show that with other parameters unchanged,the larger the corner hole of the plate is,the smaller the resistance of the plate change is,but the range of change is not large;the number of pieces has a great influence on the resistance of the plate heat exchanger,with the number of pieces Increase the exchange resistance first decreases and then increases.Under a certain number,the exchange resistance has the minimum value in this range.This number is called the minimum resistance number.The resistance of board exchange increases with the increase of the flow rate,and the growth rate is faster and faster.At the same time,the change in flow rate will not change the non-uniformity of the plate exchange,that is,it will not affect the flow distribution of each flow channel inside the plate heat exchanger.The board heat exchanger resistance calculation model was used to analyze the board exchange for excessive heat resistance in a heat station.Four corresponding reform programs were proposed and the drag calculations were performed respectively.The most suitable reform program was selected for the board change.The transformation.The results of the retrofit showed that the resistance of the plate heat exchanger was reduced from 23mH₂O to 10mH₂O,a reduction of 56.5%;the power consumption per hour of the circulating pump was reduced from 139kW·h to104kW·h,a reduction of 25.2%,and the heat station was upgraded.Each heating season can save electricity 126,000 kW·h,achieved a good transformation effect,and realized the energy-saving operation of the thermal station.