Jia Dai

This open access book takes space propulsion system, gel propulsion system, and pumped liquid rocket engine as research objects and establishes and describes the theory, dynamic model, and numerical calculation method of working process of liquid/gel rocket engine. The first part of this book establishes a mathematical model for the working process of the space propulsion system, including a mathematical model for gas cylinders, an electric explosion valve, a pressure reducing valve, a storage tank, a liquid pipeline, an orifice and filter, an electromagnetic valve, a filling pipeline, and a thrust chamber. The simulation analyzes the characteristics of the start-up, steady-state, and shutdown processes of the space propulsion system. In the second part, the mathematical model of the working process of gel propulsion system is established, and the flow distribution law, water hammer characteristics, and thrust regulation characteristics of gel propulsion system are simulated and analyzed. The third part establishes a mathematical model for the working process of a pumped liquid rocket engine and simulates and analyzes the starting process characteristics of the pumped liquid rocket engine. The above theory or dynamic model reflects the latest research results of the working process of liquid/gel rocket engine. This book is used as a teaching material or reference book for teachers, students, and scientific and technological personnel engaged in the simulation analysis of the working process of liquid/gel rocket engines in the fields of aerospace, aviation, power, etc.

The role of media is becoming increasingly important as globalization has developed. Given fast social transformation and technological development in China, the consequent environmental and health risks demand citizens integrate the communication and prevention of such risks as a significant part of their daily life. This book systematically discusses the communication process of typical environmental risk issues, and the complex interaction among multiple actors, including the public, media, experts, non-governmental organizations, and government in contemporary China. From a media-centered perspective, it applies major theories in the field of environmental and risk communication, and uses a variety of empirical research methods to unravel the complicated and unique experience of communication and governance. Combining theoretical reflections with real-life examples of Chinese scenarios, the authors not only encourage a dialogue between Western and Chinese academia but also inspire students and practitioners to apply risk communication theories to solving real-life problems. The book will appeal to students, scholars, and practitioners of risk and environmental communication studies.

The role of media is becoming increasingly important as globalization has developed. Given fast social transformation and technological development in China, the consequent environmental and health risks demand citizens integrate the communication and prevention of such risks as a significant part of their daily life. This book systematically discusses the communication process of typical environmental risk issues, and the complex interaction among multiple actors, including the public, media, experts, non-governmental organizations, and government in contemporary China. From a media-centered perspective, it applies major theories in the field of environmental and risk communication, and uses a variety of empirical research methods to unravel the complicated and unique experience of communication and governance. Combining theoretical reflections with real-life examples of Chinese scenarios, the authors not only encourage a dialogue between Western and Chinese academia but also inspire students and practitioners to apply risk communication theories to solving real-life problems. The book will appeal to students, scholars, and practitioners of risk and environmental communication studies.