CD-adapco is a multinational computer software company that authors and distributes applications used for computer-aided engineering, best known for its computational fluid dynamics products.In their 2009 annual user conference, CD-adapco announced that the company had grown 22% in 2008, and they expected similar results in 2009. Professional Engineering Magazine described this as "recession-proof performance" and went on to point out that this success is especially noteworthy considering that many of the company's customers are in the automotive industry, a sector of the economy that was, at the time, suffering record low sales levels. During the financial downturn of 2009, CD-adapco launched their "No Engineer Left Behind" program, which provided free STAR-CCM+ licenses and training for displaced and unemployed engineers. Wikipedia.
Agency: European Commission | Branch: FP7 | Program: CP-FP | Phase: SST-2007-5.1-01 | Award Amount: 4.49M | Year: 2009
The automotive industry has recently seen a paradigmatic shift from design processes based on physical prototypes to a computationally aided product development process (PDP) based on virtual prototypes. To maintain the competitiveness of European car manufacturers, a significant reduction of lead development time is required. The main potential for improvement lies in further exploitation of virtual development and especially in further automation of these virtual processes through optimal design techniques. Optimal design techniques are mature and are being used in structural mechanics in the automotive industry, as well as in computational fluid dynamics (CFD) in the aeronautical industry. However, this potential has not yet been realised for CFD in the automotive industry. To integrate these methods into workflows within the routine PDP, the project will make advances with adjoint sensitivity methods, mesh-based and CAD-based shape optimisation, high-Reynolds number topology optimisation. Complete CFD optimisation workflows, i.e. chains of optimisation techniques adapted to the automotive processes for the early as well as later stages of development will be integrated into the PDP. Aspects of process stability, data management, storage, numerical efficiency will be addressed in conjunction with an analysis of current PDP practices. The current practices of organising the PDP will be analysed, the areas of potential for optimisation workflows identified and where necessary alterations of the PDP will be made. Key use cases within the design process defined by the two car manufacturers in the project will be demonstrated and the resulting reduction in lead time will be validated. European SMEs play a leading role in developing the software tools for the PDP and in supporting the car manufacturers in implementing these tools in their PDPs. Three SMEs with a track record of working with the automotive industry are partners in the project.
Lardeau S.,CD adapco |
Leschziner M.A.,Imperial College London
Physics of Fluids | Year: 2013
A direct numerical simulation study is presented, which examines the response of a spatially developing boundary layer to oscillatory spanwise wall motion imposed over a limited streamwise stretch. At the heart of the study is the dependence of the streamwise variations in skin friction and turbulence properties on the period of the oscillatory motion, with particular emphasis placed on the behaviour downstream of the start of the actuation. The friction Reynolds number just upstream of the actuation is Reτ = 520, and the wall-scaled actuation period, T+ = Tuτ2/ν, covers the range 80-200. In contrast to channel flow, the present configuration allows the processes during the transition stretch from the unactuated state to the low-drag state and the recovery from the low-drag state to be studied. Attention focuses primarily on the former. Results are included for the time-averaged turbulent stresses, their budgets and probability-density functions, as well as a range of phase-averaged properties. The study brings out, for low-drag conditions, a number of features and processes that are common with those in actuated channel flow, but suggests that the maximum drag-reduction margins are lower than those in equivalent channel flow, and that the optimum actuation period is significantly shorter. The transition to the low-drag state occurs over about 5 boundary-layer thicknesses, and is characterised by substantial oscillations in all phase-averaged properties. These oscillations, provoked at the start of the spanwise motion, propagate convectively as waves and decay as the low-drag state is approached. The interactions contributing to the oscillations are discussed as part of the analysis of phase-averaged quantities. © 2013 AIP Publishing LLC.
Vikhansky A.,CD adapco |
Physics of Fluids | Year: 2014
This article describes a generalization of the method of moments, called extended method of moments (EMM), for dispersion in periodic structures composed of impermeable or permeable porous inclusions. Prescribing pre-computed steady state velocity field in a single periodic cell, the EMM sequentially solves specific linear stationary advection-diffusion equations and restores any-order moments of the resident time distribution or the averaged concentration distribution. Like the pioneering Brenner's method, the EMM recovers mean seepage velocity and Taylor dispersion coefficient as the first two terms of the perturbative expansion. We consider two types of dispersion: spatial dispersion, i.e., spread of initially narrow pulse of concentration, and temporal dispersion, where different portions of the solute have different residence times inside the system. While the first (mean velocity) and the second (Taylor dispersion coefficient) moments coincide for both problems, the higher moments are different. Our perturbative approach allows to link them through simple analytical expressions. Although the relative importance of the higher moments decays downstream, they manifest the non-Gaussian behaviour of the breakthrough curves, especially if the solute can diffuse into less porous phase. The EMM quantifies two principal effects of bi-modality, as the appearance of sharp peaks and elongated tails of the distributions. In addition, the moments can be used for the numerical reconstruction of the corresponding distribution, avoiding time-consuming computations of solute transition through heterogeneous media. As illustration, solutions for Taylor dispersion, skewness, and kurtosis in Poiseuille flow and open/impermeable stratified systems, both in rectangular and cylindrical channels, power-law duct flows, shallow channels, and Darcy flow in parallel porous layers are obtained in closed analytical form for the entire range of Péclet numbers. The high-order moments and reconstructed profiles are compared to their predictions from the advection-diffusion equation for averaged concentration, based on the same averaged seepage velocity and Taylor dispersion coefficient. In parallel, we construct Lattice-Boltzmann equation (LBE) two-relaxation-times scheme to simulate transport of a passive scalar directly in heterogeneous media specified by discontinuous porosity distribution. We focus our numerical analysis and assessment on (i) truncation corrections, because of their impact on the moments, (ii) stability, since we show that stable Darcy velocity amplitude reduces with the porosity, and (iii) interface accuracy which is found to play the crucial role. The task is twofold: the LBE supports the EMM predictions, while the EMM provides non-trivial benchmarks for the numerical schemes. © 2014 AIP Publishing LLC.
Vikhansky A.,CD adapco
Journal of Aerosol Science | Year: 2013
A new method for solution of the multivariate population balance equations (PBEs) is presented in this work. The method uses M quadrature abscissas and weights to close the PBE. Unlike other similar methods, e.g., the direct quadrature method of moments (DQMoM) and the quadrature method of moments (QMoM), the proposed method neither inverts a badly scaled matrix nor solve a time-consuming eigenvalue problem. The method does not use any a priori discretization of the phase space and as the particles' size distribution (PSD) widens and shifts toward large characteristic sizes due to coagulation, the abscissas adaptively follow the PSD. The particles are linked by a spanning tree; the tree works as a pipeline redistributing the mass across the system and ensuring that each computational particle accounts for a prescribed fraction of the total mass and therefore the method is given the name: direct quadrature spanning tree method (DQST). © 2012 Elsevier Ltd.
Brewster R.A.,CD adapco
Journal of Fluids Engineering, Transactions of the ASME | Year: 2013
This paper provides the results of numerical calculations of pressure drops and centerline velocities for laminar fully-developed flows of non-Newtonian fluids in circular ducts. The particular non-Newtonian fluid model considered is the Cross model, which has shown the ability to model the behavior of time-independent purely-viscous fluids over a wide range of shear rates. It is shown that the Cross model is equivalent to the more recently proposed extended modified power law (EMPL) model, and an alternative formulation of the nondimensional parameters arising from the use of these models is explored. Results are presented for friction factors and nondimensional centerline velocities over a wide range of fluid and flow conditions, and it is shown that simpler constitutive models can be used in cases where the ratios of the limiting Newtonian viscosities are extreme. The implications of the results to the design and analysis of piping systems is considered, and simple and accurate correlations are provided for engineering calculations. © 2013 by ASME.
Demirdzic I.,CD adapco
Numerical Heat Transfer, Part B: Fundamentals | Year: 2015
The aim of this article is twofold: first, to present and analyze various practices for the finite-volume discretization of the diffusion term in continuum mechanics transport equations; and second, to illustrate the problems that scientific journal editors face with unscrupulous or ignorant contributors and incompetent or simply lazy and indifferent reviewers by analyzing several articles related to the finite-volume approximation of the diffusion term published by a group of authors in various refereed journals. Copyright © 2015 Taylor & Francis Group, LLC.
CD adapco and Hatamura | Date: 2010-01-20
A four-cycle engine (1) structured to introduce fresh air into a cylinder (1a) via an intake port (1d) opened/closed by intake valves (IN 1, IN2) and suck exhaust gas back into the cylinder (1a) via an exhaust port opened/closed by exhaust valves (EX1, EX2), wherein the exhaust port has a first exhaust port (1p) and a second exhaust port (1e), and the exhaust gas is sucked in back from the first exhaust port (1p) and secondary air is sucked in from the second exhaust port (1e) to form, in the cylinder (1a), a first temperature layer (T1) at a high temperature mainly composed of the exhaust gas and a second temperature layer (T2) at a temperature lower than that of the first temperature layer (T1) mainly composed of the secondary air.
CD adapco and Hatamura | Date: 2010-01-27
A four-cycle engine including a blowdown pressure wave supercharging system (40) compressing and supplying exhaust gas into a second cylinder (#1) by causing a pressure wave (blowdown pressure wave) from a combustion chamber at opening of an exhaust valve of a first cylinder (#4) to act on an exhaust port (1e) of the second cylinder (#1) and during a reopen period of an exhaust valve of the second cylinder; and a mask member (50) restraining the exhaust gas (EGR gas) compressed and supplied into the second cylinder (#1) from mixing with fresh air flowing from an intake port (1d), wherein a first temperature layer (T1) at a high temperature containing a large amount of the EGR gas in the fresh air and a second temperature layer (T2) at a temperature lower than that of the first temperature layer (T1) containing a smaller amount of the EGR gas than that of the first temperature layer (T1) in the fresh air are formed in the second cylinder (#1).
Agency: GTR | Branch: EPSRC | Program: | Phase: Research Grant | Award Amount: 96.65K | Year: 2015
Aeronautics and air transport is a vital sector of our society and economy. Aviation currently accounts for about 2% of human-induced CO2 emissions with more than 3.12 billion passengers and 48 million tons of freight worldwide last year with an average of more than 100,000 flights every day. Worldwide traffic is predicted to grow at a rate of 4% to 5% per year for the next 30 years. It simply means that more than 16 billion passengers and 25 million flights are expected in 2050. Aviation will have to find ways to meet the growing demand for air transport whilst reducing its environmental impact, specifically the level of noise and of carbon emissions. Innovative solutions are also needed to deal with fuel consumption so that aviation does not become increasingly dependent on more and more expensive energy sources. It is clear that it requires a significant step change in the technologies of future aircraft. In recent years, the development of devices known as plasma actuators has advanced the promise of controlling flows in new ways that increase lift, reduce drag and improve aerodynamic efficiencies, advances that may lead to safer, more efficient and quieter aircraft. Dielectric barrier discharge (DBD) plasma actuators consist of two electrodes, one exposed to the ambient fluid and the other covered by a dielectric material. When an A.C. voltage is applied between the two electrodes the ambient fluid over the covered electrode ionizes. This ionized fluid is called the plasma and results in a body force vector which exchanges momentum with the ambient, neutrally charged, fluid. For this project, high-resolution simulations will be carried out on the most powerful supercomputers in Europe in order to demonstrate the potential of DBD plasma actuators for the control of turbulent jets. The problem of jet noise pollution has become more severe in the past few decades due to the ever increasing number of flights, the tightening of environmental impact regulations, and the development of urban/residential areas in close proximity to airports. The scientific objective of the present project is to advance our understanding of aeroacoustic mechanisms up to the point where we can propose targeted plasma control strategies for free shear flows to tackle the problem of jet noise pollution. This research project is a first step in the development of new technologies based on plasma actuators in the aeronautic sector not only for noise reduction purposes but also potentially for mixing enhancement and for a better efficiency of jet engines. As of today, active flow control technologies have not been implemented in commercial aircraft. The large number of parameters (location of the actuator, orientation, size, relative placement of the embedded and exposed electrodes, applied voltage, frequency) affecting the performance of plasma actuators makes their development, testing and optimisation a very complicated task. Experimental approaches require numerous high-cost and time consuming trial-and-error iterations. Computational Fluid Dynamics (CFD) can complement ideally experiments with the potential to investigate in detail plasma-actuator controlled turbulent flows.
Agency: GTR | Branch: EPSRC | Program: | Phase: Research Grant | Award Amount: 100.22K | Year: 2014
To reduce the UKs greenhouse-gas emissions anywhere near the legally-binding 2050 targets, a major attack on both energy wastes and unsustainable forms of electricity production is essential. Owing to their appealing thermo-physical properties (e.g. large heat capacity relatively to the molecular weight, low boiling point, elevated density), molecularly-complex and dense gases (e.g. hydrocarbons, perfluorocarbons, siloxanes) are at the heart of realistic solutions for thermal power stations to operate efficiently on low-temperature heat sources (e.g. solar, biomass, geothermal), where they are used as substitute for water steam (e.g. organic Rankine cycle). Flow expanders in such power stations partially operate in the vicinity of the thermodynamic critical point, where the speed of sound is substantially reduced, turning the expander flow into a highly supersonic gas flow, inevitably leading to the formation of shock waves. Shock waves have the detrimental property of degrading the expander efficiency by dissipating kinetic energy into heat, and by promoting viscous losses through boundary-layer separation and thickening. Quite remarkably, and contrary to ideal gases, shock waves in molecularly-complex and dense gases can be made almost isothermal, therefore relieving part of the efficiency losses imparted by the shock wave. This remarkable property is a direct consequence of the exceptionally large number of active degrees of freedom of the gas molecule. While the prospect of efficient supersonic expanders is appealing, little is known on the implication near-isentropic shocks have on the amplification of turbulence fluctuations (which are always present in turbines). In particular, shock/turbulence interactions in dense gases can lead to the emission of energetic acoustic waves, which are significantly more powerful than in standard ideal gases. If present, such acoustic forcing can erode the expected turbine efficiency, generate vibrations and cause premature blade fatigue. The proposed research will establish a robust and fundamental understanding of sound emission from shock/turbulence interactions in dense gases, and provide a new understanding of the underlying physics, which will allow the development of predictive tools that can inform future design choices.