Research On The Theory And Methodology Of Thermoeconomic Decision For Piping Systems

Fluid is generally transported in piping that connects fluid sources with users and belongs to a typical type of energy system. Piping is widely used in power equipment,industrial production,person's life and so on. For the design,operational analysis,optimization,control,and improvement of piping,it is necessary to combine the consideration of technology,energy and economy. In order to improve thermoecomomy of piping system,i.e. saving energy and reducing cost,the thermoeconomic synthetical problem about piping has been deeply researched by the author of this paper,The main creative research results are outlined as following:1 The theory of optimal thermoeconomic synthetical design of a piping system has been proposed This theory solves successfully the synthetical problem among technology,energy and economy of piping,and solves successfully the coupling problem between the layout structure optimization and the parameter optimization. Adopting the theory the designed piping have the property of minimum of energy loss and cost,as well as excellent technical quality.2 The theory of thermoeconomic isolation on chain type energy systems has been proposed. This theory based on known parameters located at entrance and exit of each unit in the system,adjusts the unknown value of exergy cost back and forth and makes them convergent. The existence of convergence has been proved and meanwhile it achieves that the sum of local optimization becomes system optimization on chain energy systems.3 The thermoeconomic theory about the renovation of energy systems has been proposed. To the peculiarity of energy system,a new concept about thermoecomomic life and a new parameter about function depreciation of components are introduced. Based on the concept and the parameter,equivalence decision rule for unitary and compound energy systems is established,and the decision models about of thermoeconomic life suitable to unitary and compound energy systems are derived,which constitute the renovation theory.4 The decision method about the thermoeconomic life of piping insulation equipment has been proposed.5 The method of bottleneck diagnosis about energy systems has been proposed6 The universal simulation method based on elimination of residual on nodes has been applied successfully in the analysis of flow network in energy system.7 The investigation of the thermoeconomic performance of an existing facility used for thermal fatigue experiments of aircraft canopy reveals the possibility and practicability of taking measures to improve it significantly. A piping system with alternative variation of flow temperature exists in this facility.