All Outputs (40)

A novel method for boundary layer flow that uses asymptotics and the Wiener-Hopf technique (2024)
Thesis
Adamu, H. (2024). A novel method for boundary layer flow that uses asymptotics and the Wiener-Hopf technique. (Thesis). University of Salford

We consider the theory by (Chadwick, 2019) on the applications of Navier-Stokeslets (NSlets) by a Green’s integral distribution of fundamental solutions in boundary layer flow which we call BL-lets. This research investigates the application of the t... Read More about A novel method for boundary layer flow that uses asymptotics and the Wiener-Hopf technique.

A mathematical model for the motion of a micro-robot consisting of three spheres linked with axially aligned retractable arms in Stokes flow that gives expressions for mean distance moved, mean drift velocity and energy efficiency of the non-reciprocal cyclic swimming motion (2023)
Journal Article
Elatrash, L., Chadwick, E., El-Mazuzi, R., Christian, J. M., Wang, Y., Adamu, H. A., & Chadwick, E. (in press). A mathematical model for the motion of a micro-robot consisting of three spheres linked with axially aligned retractable arms in Stokes flow that gives expressions for mean distance moved, mean drift velocity and energy efficiency of the non-reciprocal cyclic swimming motion. Computers and Fluids, 266, https://doi.org/10.1016/j.compfluid.2023.106064

The problem studied was the non-reciprocal cyclic swimming motion of three spheres linked with axially aligned retractable arms in Stokes flow. The arms are assumed to be able to retract at a steady speed to half their length, and then at a later tim... Read More about A mathematical model for the motion of a micro-robot consisting of three spheres linked with axially aligned retractable arms in Stokes flow that gives expressions for mean distance moved, mean drift velocity and energy efficiency of the non-reciprocal cyclic swimming motion.

Existence and smoothness of the Navier-Stokes equation using a Boundary Integral representation (2023)
Conference Proceeding
Chadwick, E. (in press). Existence and smoothness of the Navier-Stokes equation using a Boundary Integral representation.

In the current study we determine existence and smoothness of the Navier-Stokes equation as described in the Millennium problem [1]. This considers an exterior space-time domain where the incompressible Navier-Stokes equation and continuity equation... Read More about Existence and smoothness of the Navier-Stokes equation using a Boundary Integral representation.

Existence, Smoothness and Uniqueness (in smooth space) of the Navier-Stokes equation by using a new Boundary Integral representation (2023)
Journal Article
Chadwick, E. Existence, Smoothness and Uniqueness (in smooth space) of the Navier-Stokes equation by using a new Boundary Integral representation. https://doi.org/10.48550/arXiv.2305.14219. Manuscript submitted for publication

Consider an exterior space-time domain where the incompressible Navier-Stokes equation and continuity equation hold with no bodies or force fields present, and smooth velocity at initial time. This is equivalent to the velocity being impulsively inst... Read More about Existence, Smoothness and Uniqueness (in smooth space) of the Navier-Stokes equation by using a new Boundary Integral representation.

A novel approach of testing NSlet representation using the classical Blasius flow past a semi-infinite flat plate (2023)
Conference Proceeding
Adamu, H. A., Chadwick, E. A., Borresen, J., Dang, B. C., & Darghoth, R. (in press). A novel approach of testing NSlet representation using the classical Blasius flow past a semi-infinite flat plate.

Consider the new theory by Chadwick [1] that describe the incompressible Navier-Stokes equations by an integral distribution of Navier-Stokes fundamental solutions called NSlets. This paper tests this theory against the classical non-linear Blasius p... Read More about A novel approach of testing NSlet representation using the classical Blasius flow past a semi-infinite flat plate.

Using triple deck theory for flow past a finite flat plate as a benchmark to test the Boundary Integral NSlet representation (2023)
Conference Proceeding
Dang, B. C., & Chadwick, E. A. (in press). Using triple deck theory for flow past a finite flat plate as a benchmark to test the Boundary Integral NSlet representation.

Consider the new theory by Chadwick [1] that describe the incompressible Navier-Stokes equations by an integral distribution of Navier-Stokes fundamental solutions called NSlets. Let us test this against triple deck theory for flow past a finite flat... Read More about Using triple deck theory for flow past a finite flat plate as a benchmark to test the Boundary Integral NSlet representation.

An optimisation of a chordwise slot to enhance lateral flow control on a UCAV (2022)
Journal Article
Ali, U., Chadwick, E., & Sugar-Gabor, O. (2022). An optimisation of a chordwise slot to enhance lateral flow control on a UCAV. Incas Bulletin, 14(4), 3-17. https://doi.org/10.13111/2066-8201.2022.14.4.1

This research aims to optimise a chordwise slot so that lateral flow control of a flying wing configuration can be enhanced. This was achieved by maximising the airflow rate over the trailing edge control surfaces of the wing. A higher rate of airf... Read More about An optimisation of a chordwise slot to enhance lateral flow control on a UCAV.

An experimental test for the existence of the Euler wake velocity, validating Eulerlet theory by using a bluff body in a low-speed wind tunnel (2020)
Thesis
Chalasani, K. An experimental test for the existence of the Euler wake velocity, validating Eulerlet theory by using a bluff body in a low-speed wind tunnel. (Thesis). University of Salford

The application of manoeuvrability problems in aerodynamics mainly works for Reynolds average Navier-Stokes equations particularly for a uniform, steady flow past a fixed body. Further, consider large Reynolds number such that the flow is not turbule... Read More about An experimental test for the existence of the Euler wake velocity, validating Eulerlet theory by using a bluff body in a low-speed wind tunnel.

Uniform flow past a closed body at low Reynolds number employing a novel matching in a boundary element formulation (2020)
Journal Article
Dang, B., & Chadwick, E. (2020). Uniform flow past a closed body at low Reynolds number employing a novel matching in a boundary element formulation. Engineering Analysis with Boundary Elements, 119, 95-104. https://doi.org/10.1016/j.enganabound.2020.07.008

Consider a two dimensional steady low Reynolds number flow past a circular cylinder. A boundary integral representation that matches an outer Oseen flow and inner Stokes flow is given, and the matching error is shown to be smallest when the outer dom... Read More about Uniform flow past a closed body at low Reynolds number employing a novel matching in a boundary element formulation.

A novel boundary element method for low Reynolds number external flow of biological fluid dynamics (2020)
Thesis
Dang, B. A novel boundary element method for low Reynolds number external flow of biological fluid dynamics. (Thesis). University of Salford

Consider two dimensional low Reynolds number flow past a body. In this thesis, the problems of steady flow past a circular cylinder, steady flow past an elliptical cylinder, and the motion of a generic tail-like body are investigated. The theoretical... Read More about A novel boundary element method for low Reynolds number external flow of biological fluid dynamics.

The theory and application of Navier-Stokeslets (NSlets) (2019)
Journal Article
Chadwick, E. (2019). The theory and application of Navier-Stokeslets (NSlets). Physics of Fluids, 31(10), 107103. https://doi.org/10.1063/1.5119331

Consider a closed body moving in an unbounded fluid that decays to rest in the far-field and governed by the incompressible Navier-Stokes equations. By considering a translating reference frame, this is equivalent to a uniform flow past the body. A... Read More about The theory and application of Navier-Stokeslets (NSlets).

The leading order equivalence of Oseen’s and Imai’s representations (2019)
Conference Proceeding
Adamu, H., & Chadwick, E. The leading order equivalence of Oseen’s and Imai’s representations. In C. Fresneda-Portillo (Ed.), Proceedings of the 12th UK Conference on Boundary Integral Methods UKBIM12

Consider the far-field behind a body in a steady, two-dimensional uniform flow field. In the far-field the Oseen linearisation is valid, and in the far-field wake Imai’s asymptotic expansion is applicable. The fundamental solution Green’s function o... Read More about The leading order equivalence of Oseen’s and Imai’s representations.

A Green’s integral representation for the two-dimensional steady Navier-Stokes equation (2019)
Conference Proceeding
Chadwick, E. (2019). A Green’s integral representation for the two-dimensional steady Navier-Stokes equation. In . C. Fresneda-Portillo (Ed.), Proceedings of the 12th UK Conference on Boundary Integral Methods UKBIM12

Consider steady uniform flow past a fixed, closed body in an unbounded domain governed by the incompressible Navier-Stokes equations. A velocity representation is given as an integral distribution of Green’s functions of the Navier-Stokes equations... Read More about A Green’s integral representation for the two-dimensional steady Navier-Stokes equation.

BEM for low Reynolds number flow past a steady circular cylinder in an unbounded domain (2019)
Conference Proceeding
Dang, B., & Chadwick, E. (2019). BEM for low Reynolds number flow past a steady circular cylinder in an unbounded domain. In C. Fresneda-Portillo (Ed.),

Consider a two dimensional steady low Reynolds number flow past a circular cylinder. The theoretical treatment in Chadwick [1] is detailed and elaborated. A Boundary Integral representation that matches an outer Oseen flow and inner Stokes flow is gi... Read More about BEM for low Reynolds number flow past a steady circular cylinder in an unbounded domain.

The theory and application of eulerlets (2019)
Journal Article
Chadwick, E., Christian, J., Kapoulas, A., & Chalasani, K. (2019). The theory and application of eulerlets. Physics of Fluids, 31(4), 047106. https://doi.org/10.1063/1.5088132

Consider a fixed body in a uniform flow field in the limit as the Reynolds number approaches infinity and the flow field remains steady. Instead of using standard techniques and theory for describing the problem, a new method is employed based upon t... Read More about The theory and application of eulerlets.

Modelling the electrical resistivity of concrete with varied water and chloride contents (2019)
Journal Article
Xiang, N., Wang, Y., Oleiwi, H., Chadwick, E., Yao, G., Augusthus Nelson, L., …Shabalin, I. (2020). Modelling the electrical resistivity of concrete with varied water and chloride contents. Magazine of Concrete Research, 72(11), 552-563. https://doi.org/10.1680/jmacr.18.00198

The electrical resistivity of concrete is an important property in the assessment of reinforcement corrosion in concrete and an essential parameter in the design and operation of cathodic protection for reinforced-concrete (RC) structures. Water and... Read More about Modelling the electrical resistivity of concrete with varied water and chloride contents.

Using eulerlets to model steady uniform flow past a circular cylinder (2018)
Journal Article
Chadwick, E., Christian, J., & Chalasani, K. (2018). Using eulerlets to model steady uniform flow past a circular cylinder. European Journal of Computational Mechanics, 27(5-6), 469-478. https://doi.org/10.1080/17797179.2018.1550960

Consider uniform, steady flow past a circular cylinder at Reynolds numbers 26, 36 and 40 before the flow becomes unsteady. Model the flow by using eulerlets, new Green’s functions for Euler flow. This is the first time this eulerlet model has been us... Read More about Using eulerlets to model steady uniform flow past a circular cylinder.

Making conditionally negative definite radial basis function interpolation well-conditioned by adding cardinal basis functions (2017)
Journal Article
Kazem, S., Chadwick, E. A., & Hatam, A. (2018). Making conditionally negative definite radial basis function interpolation well-conditioned by adding cardinal basis functions. Ain Shams Engineering Journal ASEJ / Ain Shams University, 9(4), 2587-2598. https://doi.org/10.1016/j.asej.2017.03.013

A class of basis functions so called well-conditioned RBF (WRBFs) has been introduced. This basis has been manipulated by adding cardinal functions to the conditionally negative definite RBFs of order 1, such as Multiquadric functions. The condition... Read More about Making conditionally negative definite radial basis function interpolation well-conditioned by adding cardinal basis functions.

Experimental study and modelling of the thermal conductivity of sandy soils of different porosities and water contents (2017)
Journal Article
and water contents. Applied Sciences, 7(2), 119. https://doi.org/10.3390/app7020119

This paper at first reports an experimental work to test the thermal conductivity of formulated sandy soil specimens of different porosities and water contents. Both needle probe and hot-plate methods were conducted and compared. It has been confirme... Read More about Experimental study and modelling of the thermal conductivity of sandy soils of different porosities and water contents.

Flow control and high-lift performance for flying-wing manned Combat Air Vehicle Configurations by inserting lots (2016)
Journal Article
Ali, U., & Chadwick, E. (2016). Flow control and high-lift performance for flying-wing manned Combat Air Vehicle Configurations by inserting lots. International Journal of Multiphysics, 10(2), https://doi.org/10.21152/1750-9548.10.2.117

The objectives of the present study on Unmanned Combat Air Vehicles (UCAVs) are two-fold: first to control the flow by inserting leading-edge and cross-flow slots and analysing the viscous flow development over the outer panels of a flying-wing co... Read More about Flow control and high-lift performance for flying-wing manned Combat Air Vehicle Configurations by inserting lots.