Yingru Zhao

Irreversible Otto heat engine with friction and heat leak losses and its parametric optimum criteria

A more realistic simplified model for an irreversible Otto cycle is established by considering the heat leak losses through the cylinder and internally dissipative friction, in which it is assumed that the piston velocity in the adiabatic processes obeys a pure sinusoidal law. The optimally operating region of the irreversible Otto heat engine is determined. The model avoids the usual hypotheses of endoreversible heat engines and the simple description of irreversible heat engines so that the results obtained here may include the performance characteristics of some simplified Otto cycle models.

Expressions for entropy production rate of fuel cells

On the basis of a general model of fuel cells, the entropy production rates of a fuel cell system under different conditions are derived by using theories of electrochemistry and thermodynamics. In order to analyze the influence of the irreversible losses existing in an actual fuel cell, the equivalent circuit of the fuel cell is introduced, so that the irreversible factor of the fuel cell may be determined directly as a function of the internal, leak and load resistances. Moreover, the maximum power output and efficiency of the fuel cell are calculated, the optimal operation of the fuel cell is discussed, and the matching condition of the load resistance is determined.

Perspective on the R&Ds in energy chemistry systems engineering

Energy chemistry systems engineering (ECSE), the application of the principles of system engineering in the field of energy chemistry, is a rapidly developing cutting-edge interdiscipline. It is used for various processes and systems in the domain of energy chemistry, dealing with problems of the efficient conversion, comprehensive utilization and complementary integration of material and energy with the theories, methods and techniques of system engineering, in order to achieve the optimal design, planning, decision-making, control, management and operation of the energy chemistry systems. The representative research areas of ECSE include CHP (combined heat & power)/CCHP (combined cooling & heating & power), polygeneration, heat exchanger network and internet of energy (IoE) etc. This paper intends to provide a brief report on the latest trends of interest to scientists, with discussions of important challenges and research status in related fields.

System architecture design for technology readiness assessment of NPPs' digital instrumentation and control

Conference Name:2013 International Conference on Information Engineering, ICIE 2013. Conference Address: Hong Kong, China. Time:November 1, 2013 - November 2, 2013.

Research and Design of Technology Readiness Levels Evaluating System for Digital Instrumentation and Control System

Technology Readiness Levels have a great superiority to evaluate new technologies, and have been adopted by U.S. Congress General Accountability Office, Department of Defense and will be considered in numerous other organizations. In this study, Technology Readiness Levels are customized to assess the Digital Instrumentation and Control system of nuclear power plants. The Technology Readiness Levels evaluation system based on Browser/Server structure is designed. The flow chart of the evaluation system, automatic data analysis system, and the tables relation of database are presented. The Browser/Server structure enables multi-experts use Browser to assess the Digital Instrumentation and Control system of nuclear power plants in different places through the Internet. The Technology Readiness Levels evaluation system can easy the organizing work and reduce fees of Technology Readiness assessment works of Digital Instrumentation and Control system.