Suitability of light scattering technique for measurements of water droplets in turbine wet steam flows

International audienceSuitability of light scattering technique for measurements of droplets in turbine wet steam flow depends on a variety of parameters. This paper examines all relevant aspects for droplet measurements inside low pressure steam turbines. On basis of light scattering theory, influence of these aspects for a distinct measurement of droplets is investigated. After clarification of these factors, a discussion on measurement errors is given comprising errors that lie within the physics of light scattering theory as well as those caused by the measurement configuration. Possible avoidance by selection of proper measurement equipment and an elaborate design and setup of the probe is described including an estimation on each errors significance on measurement results. Light scattering technique is then evaluated on its applicability for low pressure steam turbines. It is argued in favor of light scattering that only measurements of single droplets provide insight into the fundamentals of droplet condensation and growth during expansion. Requirements for measurements with a light scattering probe in steam turbines regarding the system's design and composition are pointed out. Finally an outlook on present and future developments is given

institutional innovation from the bottom up?

A sustainable economy fulfills societal needs in a fundamentally different way to the current economic system. Improvements to the efficiency of existing technologies or practices appear insufficient for achieving sustainable development within the planetary boundaries. Disruptive, systemic and transformational changes appear necessary in order to replace existing technologies and practices to establish a sustainable economy. Such innovations often start out in niches; however, the scaling up and the ultimate replacement of current socio-technical systems requires governance to allow for the coordination of actors, the reorganization of socio-technical systems and the mobilization and allocation of resources. As governmental institutions are part of the current (non-sustainable) systems and thereby fail to provide coherent, integrated and transformative governance, we explore whether institutional innovation from non-state actors can step in to provide governance of transformation processes. Based on explorative qualitative case studies of networks in the food sector, city planning and reporting tools, we analyze the potential of bottom-up institutional innovations to coordinate actors in transformation processes

Suitability of light scattering technique for measurements of water droplets in turbine wet steam flows

International audienceSuitability of light scattering technique for measurements of droplets in turbine wet steam flow depends on a variety of parameters. This paper examines all relevant aspects for droplet measurements inside low pressure steam turbines. On basis of light scattering theory, influence of these aspects for a distinct measurement of droplets is investigated. After clarification of these factors, a discussion on measurement errors is given comprising errors that lie within the physics of light scattering theory as well as those caused by the measurement configuration. Possible avoidance by selection of proper measurement equipment and an elaborate design and setup of the probe is described including an estimation on each errors significance on measurement results. Light scattering technique is then evaluated on its applicability for low pressure steam turbines. It is argued in favor of light scattering that only measurements of single droplets provide insight into the fundamentals of droplet condensation and growth during expansion. Requirements for measurements with a light scattering probe in steam turbines regarding the system's design and composition are pointed out. Finally an outlook on present and future developments is given