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VERIFICATION OF DIAPHRAGM ANALYSIS - EXPRO PLUS

on 24 February 2015

ESA Open Invitation To Tender AO8182
Open Date: 18/02/2015
Closing Date: 15/04/2015

Status: ISSUED
Reference Nr.: 14.123.12
Prog. Ref.: TRP
Budget Ref.: E/0901-01 - TRP
Special Prov.: B+DK+F+D+I+NL+E+S+CH+GB+IRL+A+N+FIN+POR+GR+LUX+CZ+RO+PL
Tender Type: C
Price Range: 200-500 KEURO
Establishment: ESTEC
Directorate: Directorate of Technical & Quality Manag
Department: Mechanical Engineering Department
Division: Propulsion & Aerothermodynamics Division
Contract Officer: Magne-Lie, Karine
Last Update Date: 18/02/2015
Update Reason: Tender issue

The herein proposed tasks are part of an overall development approach for diaphragm tanks. To achieve the objective it will be necessary to first establish mathematical models allowing the analytical verification of selected diaphragm design due to expected mission environment and with respect to both function and structural integrity and validate these mathematical models by means of tests. The investigations within this activity will consider the following operating conditions of the diaphragm: i) The 3-dimensional characteristics of the membrane deformation taking place in the course of the filling process. In this regard the main focus will be the validation of the mathematical models by means of appropriate tests. ii) The significance of the diaphragm for the tank performance under lateral sloshing conditions. Due to the higher complexity of the underlying physical processes and the rather low initial development status the investigations on the sloshing phenomenon have the character of feasibility study concerning both testing and analysis. After mastering the above mentioned main goals, investigations of diaphragms behaviour in a micro-gravity environment are aimed to be considered in to be defined future programmes. The current approach to solving this problem relies on combined Eulerian-Lagrangian analysis, in particular using the capabilities of the commercial FE software package ABAQUS. The advantages of this method are mainly linked to an independent discretization of the fluidic and structural domain and in the Eulerian formulation of the liquid, which does not imply restrictions in terms of deformation limits. At the current status stable-running computations of the tankfilling process have been performed. The analysis results fit qualitatively well with the membrane deformation behaviour observed during a filling test on a set-up with a transparent dome. As a further fundamental part of the above outlined overall development approach the objectives of the proposed tasks on hand are: a) the experimental verification of the expected, i.e. analysed membrane deformation behaviour under tank filling conditions b) the preparation of analytical and experimental verification of the membranes behaviour under sloshing conditions c) the definition of future development steps, based on the results achieved at that time, necessary for verification of analysis of real tank configurations Procurement Policy: C(1) = Activity restricted to non-prime contractors (incl. SMEs). For additional information please go to EMITS news "Industrial Policy measures for non-primes, SMEs and R&D entities in ESA programmes".

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