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The purpose of this paper is to present a procedure to design an experimental setup meant to validate an innovative approach for simulating, via computational fluid dynamics, a high-pressure gas release from a rupture (e.g. on an offshore oil and gas platform). The design is based on a series of scaling exercises, some of which are anything but trivial.

The experimental setup is composed of a wind tunnel, the instrumented scaled (1:10) mock-up of an offshore platform and a gas release system. A correct scaling approach is necessary to define the reference speed in the wind tunnel and the conditions of the gas release to maintain similarity with respect to the real-size phenomena. The scaling of the wind velocity and the scaling of the gas release were inspired by the approach proposed by Hall et al. (1997): a dimensionless group was chosen to link release parameters, wind velocity and geometric scaling factor.

The theoretical scaling approaches for each different part of the setup were applied to the design of the experiment and some criticalities were identified, such as the existence of a set of case studies with some release parameters laying outside the applicability range of the developed scaling methodology, which will be further discussed.

The resulting procedure is one of a kind because it involves a multi-scaling approach because of the different aspects of the design. Literature supports for the different scaling theories but, to the best of the authors’ knowledge, fails to provide an integrated approach that considers the combined effects of scaling.

The research activity presented in this paper has the objective of developing models for the evaluation of technological risk and loss of production due to failures, which are among the criterions that enable the choice of optimal scenarios for energy supply. This activity is based on the European Project “Risk of Energy Availability: Common Corridors for Europe Supply Security” (REACCESS), which aims to develop an analytical tool to analyse scenarios for future secure European Union (EU) energy supply.

The paper proposes an innovative approach, since nowadays a generalised analytic model for risk assessment in large‐scale energetic systems does not exist. In particular, the methodology adopted includes models to assess risk for people safety, risk for the environment and availability for corridors and the related infrastructures. As regards technological risk, accidents producing loss of lives in the population and environmental damage are taken into account; while for the loss of production primary attention is paid to technical failures and maintenance.

Since the analytic models developed perform a large‐scale assessment, they must be flexible and simplified to adapt to different situations and to be easily updated when different future scenarios are investigated. Details of the analysis depend on the precision of data collected and inserted in the models. The damage assessment is affected by deficiency and uncertainties related to territorial and statistical data. Nevertheless, the outcomes obtained for each energy commodity are reasonable and often comparable to literature data.

Based on this study output, technological risk can be considered, more systematically than in the past, in the selection of EU strategies for future energy supply. The corridors social cost is included in future strategies selection, in addition to purely economical and environmental evaluations.