Laboratory-scale steam power plant study - rankine cycler™ comprehensive experimental analysis

Abstract

The Rankine Cycler™ steam turbine system, produced by Turbine Technologies, Ltd., is a tabletop-sized working model of a fossil-fueled steam power plant. It is a tool for hands-on teaching of fundamentals of thermodynamics, fluid mechanics, heat transfer, and instrumentation systems in an undergraduate laboratory. Inevitably, when a power generation plant is scaled-down and it has few efficiency-enhancing components (e.g., feedwater heaters), energy losses in components will be magnified, substantially lowering the cycle efficiency from values presented in textbooks and realized in real world power plants. Therefore, faculty and students at two different universities undertook a study of the Rankine Cycler to determine its effectiveness as a pedagogical tool and to characterize the device with a comprehensive experimental analysis. This analysis can be useful to faculty and students who use the equipment and can also be useful to potential customers of Turbine Technologies. This is the authors' third and final paper about the Rankine Cycler, continuing the work started in 2004-05. In the first paper two important objectives were met. First, to determine the effectiveness of the Rankine Cycler as a learning tool, an indirect assessment was performed (i.e., a measure of student opinion). The results were positive. Second, a parametric study of the effects of component losses on Rankine Cycler thermal efficiency was performed. The results showed that the range of component losses used in the parametric study accurately reflect experimental thermal efficiencies for the device, and pointed to future experimental work. In the second paper, two further objectives were met. First, assessment of the RC's effectiveness as a learning tool was continued. The indirect assessment was extended through more student surveys, and a more direct assessment was performed based on graded student reports and exams. Assessment results were positive and pointed toward how the equipment can be used in the best possible manner in the undergraduate curriculum. Second, experimental work performed to characterize the Rankine Cycler was reported. Multiple steady state runs were performed to seek the optimum operating point and methods for measuring steam flow more accurately were proposed. For this paper, significant experimental work was concluded to further characterize the Rankine Cycler. First, more steady state runs were performed at higher voltages than previous tests to determine an optimum operating point. Second, a method for accurate steam flow measurement was developed. Third, the fuel (LP) flow calibration was verified. Fourth, the turbine and generator were studied to discover discrepancies in power output. Finally, boiler efficiency is discussed along with some recommendations. © American Society for Engineering Education, 2007.