Parametric study toward optimization of blowing and suction locations for improving lift-to-drag ratio on a Clark-Y airfoil

Abstract

Reynolds-averaged Navier-Stokes simulations (RANS) of flows around a Clark-Y airfoil with uniform blowing (UB) and uniform suction (US) are performed aiming at improvement of the airfoil performance. First, the control effect in the case with single UB or US applied on the airfoil surface is investigated at the various control locations. The magnitude of UB/US is 0.14% of the free-stream velocity, and the control region is set at four different locations on the upper and lower surfaces. The Reynolds number based on the chord length and the angle of attack are 1.5 × 10 6 and 0 • , respectively. It is found that the friction drag is decreased/increased by single UB/US control. It is also found that UB on the lower surface or US on the upper surface improves the lift-to-drag ratio, while UB on the upper surface or US on the lower surface worsens it. In the combined control of UB and US having the equal flow rate, the magnitude of blowing and suction is set at 0.14% or 0.26% of the free-stream velocity. The locations of blowing/suction and flow conditions are the same as those in the cases with either UB or US only. The simulation result suggests that the lift-to-drag ratio is improved by the combined control of UB on the lower surface and US on the upper surface. In particular, the lift-to-drag ratio is most improved by a combination of UB on the lower rear surface and US on the upper rear surface. In contrast, a combined control of UB on the upper front surface and US on the lower rear surface is identified as the most effective case for the friction drag reduction only.

Drag Assessment for Boundary Layer Control Schemes with Mass Injection

“…The discussion of the difference and meaning of the body and wake-survey drag in presence of fluid sources, object of the present manuscript, may seem trivial at first to an expert aerodynamicist and has been discussed, albeit not directly in the context of flow control, in classic literature such as by Schlichting & Gersten (2006) [43, pag.311]. Nonetheless, recent works on the topic of turbulent drag reduction via wall-normal blowing [24,29,30], including ours [22,25], overlooked this aspect or did not address it properly, thereby possibly overestimating the control performance by not considering the inclusive drag or pointing at an only apparent disagreement of the different drag measurements.…”

“…In apparent contradiction to this expectation numerical studies of airfoils with blowing reveal a significant reduction of the total drag experienced by the airfoil [22,24]. Furthermore, it was shown that the scheme of uniform blowing on the pressure side of an airfoil has a prospect of significant performance enhancement resulting from both pressure and friction drag reduction [25].…”

Perbandingan Analisis Kestabilan Statik Uav Meniru Cessna 172 Dengan Dan Tanpa Sayap Morphing Menggunakan Perangkat Lunak Xflr5

“…Wing dari UAV menggunakan airfoil jenis Clark Y, dengan alasan airfoil tersebut memiliki bentuk geometri yang sederhana dan banyak diaplikasikan pada pesawat kebanyakan UAV fixed wing, selain itu jenis airfoil tersebut mampu meminimalkan drag ketika sedang terbang (Ohashi et al, 2020), serta airfoil jenis ini dapat memberikan coefficient lift yang lebih tinggi dari jenis lainnya sehingga dapat cepat menghasilkan gaya angkat pada sudut serang minimum (Dhafin at al., 2019).…”

Konseptual Desain Pesawat UAV Meniru Cessna 172 Dengan Konfigurasi Sayap Morphing Untuk Misi Trainer

“…Sedangkan untuk jenis airfoil yang dipilih yang akan digunakan pada sayap UAV dipilih airfoil Clark-Y dengan alasan selain bentuk geometri airfoil tersebut yang lebih sederhana dan cocok bagi pemula, terlebih airfoil tersebut juga dapat meminimalisir drag friction pada saat terbang [18]. Selain daripada itu alasan lainnya pemilihan airfoil Clark-Y untuk komponen dari sayap UAV yang akan didesain adalah karena airfoil jenis ini memiliki nilai coefficient lift yang lebih tinggi dari jenis lainnya sehingga dapat cepat menghasilkan gaya angkat [19].…”