Comparative study of working fluids for OTEC power plants

The effect of three different working fluids (ammonia, propane, and freon-114) on the size of OTEC heat exchangers is analyzed. Seven different combinations of shell-and-tube heat exchangers are considered. For each combination, a simple computer model of the OTEC power system is used to compare the three fluids. The comparison is made on the basis of A/W/sub net/, where A is the total heat transfer area (evaporator plus condenser) and W/sub net/ is the net power output of the plant. Overall, ammonia is shown to be the best fluid (i.e., it yields the lowest value of A/W/sub net/), although in some cases only by a small margin. The thermophysical property that gives ammonia its general superiority is its relatively high thermal conductivity. The report also discusses heat exchanger design problems associated with liquid entrainment and boiling liquid superheat

Report on ALoSP implementation in EUROCONTROL Member States, including proposal for the initial definition and guidance to support its harmonised implementation in Europe

Support to reviewing implementation of Acceptable Level of Safety Performance (ALoSP) concept in EUROCONTROL Member States and development of an initial definition and guidance

Risk based life-cycle planning for flood-resilient critical infrastructure

The paper presents a risk assessment model, developed in the project oVER-FLOw and further implemented in the project CROSScade, for determining the direct and indirect impacts of flooding hazards. As a consequence of flooding, transport infrastructure and flood protection systems can be significantly damaged and cause cascading effects on other infrastructure. To achieve flood resilient infrastructure, it is necessary to assess the vulnerability of critical assets in the affected area. The model uses novel vulnerability assessment methods for embankments and bridges exposed to different flood hazard scenarios allowing the asset owners to understand risk and performance of their infrastructure. Scarce financial resources are allocated on the critical assets allowing significant cost savings and avoiding the waste of non-renewable resources in strengthening large sections which have sufficient resilience. The consequence analysis is based on an improved quantification model for direct and indirect impacts of different flood hazard scenarios used for risk mapping of the affected area