Study of pressure losses in tubing and fittings Final report, Jun. 1, 1964 - Jun. 1, 1966

Steady state and transient fluid flow equations for predicting friction and pressure in tubing and fitting systems - computer progra

Active flow control systems architectures for civil transport aircraft

Copyright @ 2010 American Institute of Aeronautics and AstronauticsThis paper considers the effect of choice of actuator technology and associated power systems architecture on the mass cost and power consumption of implementing active flow control systems on civil transport aircraft. The research method is based on the use of a mass model that includes a mass due to systems hardware and a mass due to the system energy usage. An Airbus A320 aircraft wing is used as a case-study application. The mass model parameters are based on first-principle physical analysis of electric and pneumatic power systems combined with empirical data on system hardware from existing equipment suppliers. Flow control methods include direct fluidic, electromechanical-fluidic, and electrofluidic actuator technologies. The mass cost of electrical power distribution is shown to be considerably less than that for pneumatic systems; however, this advantage is reduced by the requirement for relatively heavy electrical power management and conversion systems. A tradeoff exists between system power efficiency and the system hardware mass required to achieve this efficiency. For short-duration operation the flow control solution is driven toward lighter but less power-efficient systems, whereas for long-duration operation there is benefit in considering heavier but more efficient systems. It is estimated that a practical electromechanical-fluidic system for flow separation control may have a mass up to 40% of the slat mass for a leading-edge application and 5% of flap mass for a trailing-edge application.This work is funded by the Sixth European Union Framework Programme as part of the AVERT project (Contract No. AST5-CT-2006-030914

Applications of aerospace technology to petroleum extraction and reservoir engineering

Through contacts with the petroleum industry, the petroleum service industry, universities and government agencies, important petroleum extraction problems were identified. For each problem, areas of aerospace technology that might aid in its solution were also identified, where possible. Some of the problems were selected for further consideration. Work on these problems led to the formulation of specific concepts as candidate for development. Each concept is addressed to the solution of specific extraction problems and makes use of specific areas of aerospace technology

Experimental and Numerical Modeling of Fluid Flow

This Special Issue provides an overview of the applied experimental and numerical flow, models, which are used to investigate fluid flow in complex situations. The investigated problems are related to fundamental processes or new applications. As demonstrated, the field of the application of experimental and numerical flow models is constantly expanding

Development of boundary conditions for building drainage system components through novel numerical, laboratory and photogrammetric methods

Improvements in public health through better sanitary plumbing systems has been mainly due to the prevention afforded by barrier technologies to the ingress of foul air, which can contain toxic gases and pathogens, notwithstanding the nuisance of malodour. The main defence against this ingress is the ‘trap seal’ which comes in two forms; the ‘water trap seal’ and the ‘waterless trap seal’. Whilst these devices form effective barriers, they are vulnerable to, or can produce, transient air pressure fluctuations in the system which can lead to seal loss. Greater understanding of the characteristics of these devices is essential for the development of better protection strategies. The development of novel analytical techniques is central to this research as it increases computer model resolution at these important system extremities. Current methods employ a laboratory only approach, whereby a single loss co-efficient is developed. These laboratory derived boundary conditions are inherently static and in the case of the waterless trap seal, ignore structure flexibility. This research has produced new methodologies to evaluate performance and generate dynamic boundary conditions suitable for inclusion in an existing 1-D Method of Characteristics based model, AIRNET, which solves for pressure and velocity via the St. Venant equations of continuity and momentum in a finite difference scheme. The first novel technique developed uses photographic image and pressure data, transformed via photogrammetric and Fourier analysis to produce mathematical representations of the opening and closing of a waterless trap under transient pressures. The second novel technique developed focusses on the dynamic response of a water trap seal. Current boundary conditions use a steady state friction factor, ignoring separation losses. Analysis via ANSYS CFX allowed a frequency dependent dynamic representation of velocity change in the water trap seal to be developed, integrating unsteady friction and separation losses for the first time. Incorporation of these new boundary conditions in AIRNET confirms that frequency dependent whole system responses are possible and more realistic, reflecting both laboratory and on-site observations

Space shuttle orbiter heat pipe applications. Volume 2: Final report

For abstract, see

Numerical modelling of local scour with computational methods

Evaluating bed morphological evolution (specifically the scoured bed level) accurately using computational modelling is critical for analyses of the stability of many marine and coastal structures, such as piers, groynes, breakwaters, submarine pipelines and even telecommunication cables. This thesis considers the coupled hydrodynamic and morphodynamic modelling of the local scour around hydraulic structures, such as near a vertical pile or near a horizontal pipe. The focus in this study is on applying a fluid-structure interaction (FSI) approach to simulate the morphodynamical behaviour of the bed deformation, replacing the structural (i.e. solid mechanics) equation by the sediment continuity equation or Exner equation. Specifically, this works presents a novel method of mesh movement with anisotropic mesh adaptivity based on optimization for simulating local scour near structures with discontinuous Garlerkin (DG) discretisation methods for solving the flow field. Amongst the other goals of this work is the validation of the proposed procedure with previously performed laboratory as well as two- and three-dimensional numerical experiments. Additionally, performance is considered using an implementation of the methodology within Fluidity (http://fluidityproject.github.io/), an open-source, multi-physics, computational fluid dynamics (CFD) code, capable of handling arbitrary multi-scale unstructured tetrahedral meshes and including algorithms to perform dynamic anisotropic mesh adaptivity and mesh movement. The flexibility over mesh structure and resolution that these optimisation capabilities provide makes it potentially highly suitable for accounting the extreme bed morphological evolution close to a fixed solid structure under the action of hydrodynamics. Galerkin-based finite element methods have been used for the hydrodynamics (including discontinuous Galerkin discretisations) and morphological calculations, and automatic mesh deformation has been utilised to account for bed evolution changes while preserving the validity and quality of the mesh. Finally, the work extends the scope in regards of computational methods and considers scour modelling with pure Lagrangian and meshless methods such as smoothed particle hydrodynamics (SPH), which have also become of interest in the analysis and modelling of coastal sediment transport, particularly in scour-related processes. The SPH modelling is considered in a two-phase, flow-sediment fully Lagrangian scour simulation where the discrete-particle interaction forces between phases are resolved at the interface and continuous changes in the bed profile are obtained naturally.Open Acces