Searched for: author%3A%22Boersma%2C+B.J.%22
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Çelik, M. (author), Patki, Mrunal (author), Paulussen, Geert (author), de Jong, W. (author), Boersma, B.J. (author)
In a conventional continuous annealing line, the energy supplied to steel strip during heating is not recovered while cooling it. Therefore, an alternative heat transfer technology for energy efficient continuous annealing of steel was developed. This technology enables reusing the heat extracted during cooling of the strip in the heating...
journal article 2019
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Çelik, M. (author), Devendran, Kathikeyan (author), Paulussen, Geert (author), Pronk, Pepijn (author), Frinking, Ferry (author), de Jong, W. (author), Boersma, B.J. (author)
A new concept for energy efficient annealing of steel strip comprises of multiple rotating heat pipes. Each heat pipe extracts heat from the cooling strip which is reused to increase the temperature of the heating strip. In this context, the heat transfer between the steel strip and the rotating heat pipe is investigated. When the strip is...
journal article 2018
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Çelik, M. (author), Paulussen, Geert (author), van Erp, Dennis (author), de Jong, W. (author), Boersma, B.J. (author)
Rotating wickless and stationary capillary cylindrical heat pipes are widely used heat transfer devices. Transient behavior of such heat pipes has been investigated numerically with computational fluid dynamics and lumped parameter models. In this paper, the advantages of both methods are combined into a novel engineering model that is low in...
journal article 2018
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Sengupta, U. (author), Nemati, H. (author), Boersma, B.J. (author), Pecnik, R. (author)
This work investigates fully developed turbulent flows of carbon-dioxide close to its vapour-liquid critical point in a channel with a hot and a cold wall. Two direct numerical simulations are performed at low Mach numbers, with the trans-critical transition near the channel centre and the cold wall, respectively. An additional simulation...
journal article 2017
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Patel, A. (author), Boersma, B.J. (author), Pecnik, R. (author)
Direct numerical simulation of fully developed, internally heated channel flows with isothermal walls is performed using the low-Mach-number approximation of Navier-Stokes equation to investigate the influence of temperature-dependent properties on turbulent scalar statistics. Different constitutive relations for density ρ, viscosity μ, and...
journal article 2017
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Patel, A. (author), Pecnik, R. (author), Peeters, J.W.R. (author), Boersma, B.J. (author), Hickel, S. (author), Moghadam, M.E. (author)
We investigate the effectiveness of the semi-local Reynolds number Re τ to parametrize wall-bounded flows with strong density, ρ, and viscosity, µ, gradients. Several cases are considered, namely, volumetrically heated low-Mach-number turbulent channel flows, a simultaneously heated and cooled flow with CO2 at supercritical pressure, and heated and...
book chapter 2017
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Peeters, J.W.R. (author), Pecnik, R. (author), Rohde, M. (author), van der Hagen, T.H.J.J. (author), Boersma, B.J. (author)
Heat transfer to fluids at supercritical pressure is different from heat transfer at lower pressures due to strong variations of the thermophysical properties with the temperature. We present and analyze results of direct numerical simulations of heat transfer to turbulent CO2 at 8 MPa in an annulus. Periodic streamwise conditions are imposed so...
journal article 2017
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Peeters, J.W.R. (author), Pecnik, R. (author), Rohde, M. (author), van der Hagen, T.H.J.J. (author), Boersma, B.J. (author)
Heated or cooled fluids at supercritical pressure show large variations in thermophysical properties, such as the density, dynamic viscosity and molecular Prandtl number, which strongly influence turbulence characteristics. To investigate this, direct numerical simulations were performed of a turbulent flow at supercritical pressure (CO2 at 8...
journal article 2016
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Costa, P. (author), Boersma, B.J. (author), Westerweel, J. (author), Breugem, W.P. (author)
We present a collision model for particle-particle and particle-wall interactions in interface-resolved simulations of particle-laden flows. Three types of interparticle interactions are taken into account: (1) long- and (2) short-range hydrodynamic interactions, and (3) solid-solid contact. Long-range interactions are incorporated through an...
journal article 2015
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Patel, A. (author), Peeters, J.W.R. (author), Boersma, B.J. (author), Pecnik, R. (author)
We theoretically and numerically investigate the effect of temperature dependent density and viscosity on turbulence in channel flows. First, a mathematical framework is developed to support the validity of the semi-local scaling as proposed based on heuristic arguments by Huang, Coleman, and Bradshaw [“Compressible turbulent channel flows: DNS...
journal article 2015
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Rinaldi, E. (author), Boersma, B.J. (author), Pecnik, R. (author)
We investigate the effect of temperature dependent thermal conductivity ? and isobaric specific heat c_P on the transient amplification of perturbations in a thermally stratified laminar plane Poiseuille flow. It is shown that for decreasing thermal conductivity the maximum transient energy growth is amplified with respect to the ?=1 case, while...
conference paper 2015
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We investigate the effect of temperature dependent thermal conductivity λ and isobaric specific heat c_P on the transient amplification of perturbations in a thermally stratified laminar plane Poiseuille flow. It is shown that for decreasing thermal conductivity the maximum transient energy growth is amplified with respect to the λ=1 case, while...
conference paper 2015
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We perform Direct Numerical Simulations (DNS) of a turbulent channel flow with temperature dependent density and viscosity. The Navier-Stokes equations are solved using their low Mach number formulation. In the simulations performed, the fluid is internally heated and the temperature at the walls is fixed. The friction Reynolds number based on...
conference paper 2015
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Patel, A. (author), Peeters, J. (author), Boersma, B.J. (author), Pecnik, R. (author)
We perform Direct Numerical Simulations (DNS) of a turbulent channel flow with temperature dependent density and viscosity. The Navier-Stokes equations are solved using their low Mach number formulation. In the simulations performed, the fluid is internally heated and the temperature at the walls is fixed. The friction Reynolds number based on...
conference paper 2015
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Boersma, B.J. (author), Pecnik, R. (author), Nemati, H. (author), Peeters, J.W.R. (author)
In this paper we discuss the effect of sharp property variations on the turbulent heat transfer in fluids close the critical point. The governing equations for this flow regime are discussed, a short description of the numerical tools that have been developed to study these flows is given. Finally, some results for supercritical heat transfer in...
journal article 2015
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Nemati, H. (author), Patel, A. (author), Boersma, B.J. (author), Pecnik, R. (author)
This work investigates turbulent heat transfer to a pipe flow with a fluid close to its vapour-liquid critical point. The flow is simulated using Direct Numerical Simulations (DNS) of the anelastic Navier-Stokes equations at a Reynolds number of Ret = 360, based on the friction velocity ut at the inlet and the diameter of the pipe. Turbulent...
conference paper 2013
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Vuorinen, V. (author), Yu, J. (author), Tirunagari, S. (author), Kaario, O. (author), Larmi, M. (author), Duwig, C. (author), Boersma, B.J. (author)
Large-eddy simulations (LES) based on scale-selective implicit filtering are carried out in order to study the effect of nozzle pressure ratios on the characteristics of highly underexpanded jets. Pressure ratios ranging from 4.5 to 8.5 with Reynolds numbers of the order 75?000–140?000 are considered. The studied configuration agrees well with...
journal article 2013
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Boersma, B.J. (author)
With todays supercomputers we are able to simulate flows with moderate to high Reynolds numbers. These flows show features that are not present in simulations with lower Reynolds numbers. Recently we have finished a fully resolved direct numerical simulation of a turbulent pipe flow with a bulk Reynolds number of 76,000 on a computational...
conference paper 2013
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Vuorinen, V.A. (author), Duwig, C. (author), Kaario, O. (author), Larmi, M. (author), Boersma, B.J. (author)
Large-Eddy Simulations (LES) based on scale-selective implicit filtering are carried out in order to study the effect of nozzle pressure ratios on the characteristics of highly underexpanded jets. Pressure ratios ranging from 3 to 9 with Reynolds numbers of the order 70000 to 150000 are considered. The studied configuration agrees well with...
conference paper 2013
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Boersma, B.J. (author)
In recent years there has been a considerable research effort dedicated to turbulent pipe flow. Topics of interest are, amongst others, the scaling of near wall turbulent statistics and the existence of very large scale turbulent structures at higher Reynolds numbers. These structures have been observed experimentally in boundary layers,...
conference paper 2013
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