The Experiment Research On Heat Transfer Characteristics And Scaling Thermal Resistance Of Internal Coating Steel Pipe

The efficiency of heat transfer will fall down while the potential safety hazard will increase for the existance of fouling.Many scholars both at home and abroad dedicated to the anti-fouling research.Made some achievements.Internal coating steel pipe belongs to low surface energy fluorocarbon material,it can reduce the fouling speed,which has superior performance in the field of anti-fouling.The experiment research on heat transfer characteristics and scaling thermal resistance of internal coating steel pipe were studied in this paper.Analysis on the heat transfer process of the test pipe in thermostatic waterbath.Heat transfer equations were established,thermal resistance expression of correlation method was discussed theoretically.According to the correlation method theory,with corresponding calculation,thermal resistance test-bed was established.The whole test-bed structure was made up of cold water tank,thermostatic waterbath,circulating water pump,temperature control system,flow control system,temperature measurement system,Pressure measurement system,etc.For scaling common steel pipes,scaling Teflon tubes,scaling Ptfe pipes on the test-bed,at different velocity,different temperatures,different concentrations conditions,the thermal resistance was calculated,and curves were drawn by using the result.The experimental study showed that:with velocity increasing,the thermal resistance on the coating surface reduces,when the temperature of the liquid goes up,the thermal resistance increased too,meanwhile,with concentration of the liquid increasing,the thermal resistance on the coating surface increases.The efficiency of heat transfer is between 23%-95%of former.The thermal resistance of Teflon was 0.00032(m2·?)/W,and the thermal resistance of Ptfe was 0.00094(m2·?)/W in our experiments.