Hybrid journal (It can contain Open Access articles) ISSN (Print) 1743-5447 - ISSN (Online) 1743-5455 Published by Inderscience Publishers[450 journals]
Authors:James Dent, Joshua Robson, Alessio Basso, Alexander Ellin, Atma Prakash, F.A. Hamad Pages: 89 - 104 Abstract: In this paper, the structure of the external flow field around the wing of a Lobet Ganagobie light aircraft is investigated using CFD. A model has been developed to mimic the NACA 23012 geometry and then used to simulate the flow around the 3D aerofoil. A wind tunnel is used to collect new experimental data for lift coefficient to verify the accuracy of the model at Reynolds number, Re = 0.3 × 10<SUP align=right>6</SUP>. Then, the CFD model is utilised to produce velocity streamline plots and pressure and velocity contours at higher Re(2 × 10<SUP align=right>6</SUP> − 3 × 10<SUP align=right>6</SUP>) to give a better understanding of the flow around the Lobet Ganagobie wing. The turbulence model is selected based on the comparison of experimental data with results from different CFD models. Driven by the abrupt stalling characteristics of the NACA 23012 airfoil section, the model is used to predict the position of the stagnation point on the airfoil so that a stall warning device can be sensibly located. Keywords: CFD simulation; Lobet Ganagobie wing; lift coefficient; drag coefficient; stagnation point; flow separation Citation: International Journal of Aerodynamics, Vol. 7, No. 2 (2021) pp. 89 - 104 PubDate: 2021-02-01T23:20:50-05:00 DOI: 10.1504/IJAD.2021.112707 Issue No:Vol. 7, No. 2 (2021)
Authors:Miguel Angel Aguirre, Ramiro Bracco, Fabio Milanese, MatÃas Meroniuc Pages: 105 - 126 Abstract: This paper details the design procedure of a wind tunnel aerodynamic balance. It is the six-component external balance with floating frame used in our main Eiffel-type wind tunnel. This balance has the unique feature of being able to receive full and half wind tunnel models. Firstly, a set of design requirements and specifications is defined. Then the conceptual and detailed design of the mechanism is deeply explained. Finally, an analytical model of the balance is developed and used in order to study the effect of the design loads: this allowed sizing of the load cells and the counterweights of the balance. Keywords: experimental aerodynamics; wind tunnel; external balance; floating frame; half model; full model; design procedure; force measurement Citation: International Journal of Aerodynamics, Vol. 7, No. 2 (2021) pp. 105 - 126 PubDate: 2021-02-01T23:20:50-05:00 DOI: 10.1504/IJAD.2021.112709 Issue No:Vol. 7, No. 2 (2021)
Authors:A.M. Chuen, M. Hafez Pages: 127 - 150 Abstract: Inviscid, compressible flows are described by a first-order system of hyperbolic partial differential equations in conservation form, and are solved numerically with simple schemes. These schemes show the ability to reproduce well-known solutions and benchmarks for the two-dimensional Euler equations. Finally, the schemes are used to explore the anomaly of non-unique solutions in the transonic regime. Furthermore, numerical solutions for the isentropic Euler equations with γ = 2, which are analogous to the shallow water equations, also exhibit non-uniqueness. In the appendix, results computed with OVERFLOW also exhibit non-unique solutions for the same geometries considered in the text. Keywords: transonic flows; Euler equations; isentropic Euler equations; numerical schemes; non-unique solutions; overflow code Citation: International Journal of Aerodynamics, Vol. 7, No. 2 (2021) pp. 127 - 150 PubDate: 2021-02-01T23:20:50-05:00 DOI: 10.1504/IJAD.2021.112747 Issue No:Vol. 7, No. 2 (2021)
Authors:A. Burkhead, M. Hafez Pages: 151 - 175 Abstract: The analogue of compressible inviscid flows and shallow water surface waves are studied via water table experiments. In particular, the non-uniqueness problems of transonic flows in nozzles and around airfoils are examined numerically and experimentally. Qualitative comparisons of the two results are shown for several cases. Keywords: hydraulic analogy; water table; non-unique solutions; transonic flows Citation: International Journal of Aerodynamics, Vol. 7, No. 2 (2021) pp. 151 - 175 PubDate: 2021-02-01T23:20:50-05:00 DOI: 10.1504/IJAD.2021.112748 Issue No:Vol. 7, No. 2 (2021)
Authors:Mohammad Saeedi, Ali Tarokh, Kefu Liu Pages: 176 - 194 Abstract: In the current research, a series of numerical simulations of the flow field around a typical tractor-trailer combination with and without a drag reduction device (i.e., boat tail) have been performed to study the effect of the device on wake structures and flow evolution behind the trailer. The results of the simulations have been validated through comparison of the drag coefficient against available wind-tunnel measurement data. Based on the evolution profiles and flow visualisation behind the trailer, it has been shown that the trailer wake region in proximity of the trailer rear surface is significantly influenced by the trailer boat tail. As such a quicker flow recovery, smaller recirculation bubble and lower level of turbulent kinetic energy is obtained when the boat tail is utilised. This resulted in about 8.6% decrease in the vehicle aerodynamic drag and 4.6% fuel saving based on the travelling speed of 65 mph. Keywords: drag reduction devices; aerodynamics of heavy truck; wake control; boat tail Citation: International Journal of Aerodynamics, Vol. 7, No. 2 (2021) pp. 176 - 194 PubDate: 2021-02-01T23:20:50-05:00 DOI: 10.1504/IJAD.2021.112750 Issue No:Vol. 7, No. 2 (2021)
Hybrid journal (It can contain Open Access articles)
