This work focuses on the design and optimization of a morphing-compliant system developed within project HERWINGT (Clean Aviation) aimed at generating high lift during take-off landing. The device was conceived to replace conventional flap regional aircraft in synergy with droop nose flow control system. architecture is based compliant layout, specifically selected obtain final morphed shape trailing edge wing efficient for high-lift purposes adequately smooth even cruise clean...

The focus of this paper is on some the activities performed by CIRA under framework HERWINGT project (Hybrid Electric Regional Wing Integration Novel Technologies) supported Clean Aviation Joint Undertaking and funded European Union. aim to design an innovative wing suitable for future hybrid electric regional aircraft (HER) that will contribute overall target reducing fuel burn, CO2, other GHG emissions improving aerodynamic efficiency weight. a high-lift system wings in form compliant...

DOI: 10.2514/1.J050067 A modification of the � -! shear-stress-transport turbulence model is presented in this paper with aim to improve simulation flows at a low Reynolds number. For purpose, incompressible flow number 6 10 4 , around Selig–Donovan 7003 airfoil, investigated by using several models. The focus placed on -!shear-stress-transport model: very reliable for transonic but which application low-Reynolds-number has been questioned. limits are analyzed detail. laminar bubble arising...

The effectiveness of the riblets, one most interesting drag-reduction device, is discussed in this paper. Numerical simulations by Reynolds-averaged Navier–Stokes equations with riblets properly taken into account are presented. Riblets modeled as a singular roughness problem modifying classical Wilcox boundary condition for rough walls. able to predict flow features low range (transitional roughness) where operate. A brief discussion performed validate model first Then, complex wing–body...

The purpose of this paper is to assess the capabilities newly developed tool U-ZEN, a code solving Unsteady Reynolds Averaged Navier-Stokes equations. activity being performed within CIRA project focusing on Flow Control; specific goal for CFD task simulate unsteady flow phenomena due particular fluid dynamic conditions (Mach, Reynolds, !) or time dependent boundary (e.g. control devices) around complex 3D configurations. steady state solver ZEN (Zonal Euler Navier-Stokes) has been extended...

The application of riblets on a typical regional turboprop configuration is discussed in this paper. effect the modeled as singular roughness problem by proper boundary condition at wall. model, already proposed previous paper, briefly described. drag prediction capabilities are verified showing some airfoil flow applications. Then wing–body aircraft considered. has been designed to have extended natural laminar cruise conditions. Riblets applied specifications representative combination...

Covers advancements in spacecraft and tactical strategic missile systems, including subsystem design application, mission analysis, materials structures, developments space sciences, processing manufacturing, operations, applications of technologies to other fields.

In the framework of European High Lift Programme EUROLIFT II numerical and experimental validation high lift configurations initiated in are being pursued. This present contribution describes a summary CFD improvements carried out this project. The cover turbulence modeling grid generation. More sophisticated models beyond eddy viscosity concept evaluated as well unsteady effects efficiency enhancement through wall function approaches. Different techniques to reduce number nodes unstructured...

The paper presents the results of a research activity that aims to investigate control effect fast rising pulse Dielectric Barrier Discharge actuators (DBD) in high speed flow conditions. At this aim, several experimental tests have been performed on 2D wind tunnel model subsonic and transonic conditions collect information concerning effects DBD main aerodynamic aerofoil performance. Mach number was varied between 0.4 0.85 at angles attack ranging -2° 8° Reynolds numbers Re=1.7∙10 6...

Synthetic Jet technology needs robust and fast simulation tools to grow up as expected by industrial community. The activity presented in this paper is part of a research eort carried out at the Italian Aerospace Research Center (CIRA). aim improve accuracy Reynolds-Averaged Navier-Stokes (RANS) techniques predicting eect steady unsteady flow control devices medium/high Reynolds number compressible flows. separation studied reproducing numerically low Mach 2D over an hump model which has...

This paper presents numerical simulations of laminar separation bubbles. The main aim is to investigate the capability RANS approach reproduce this important feature low-Reynolds number flows. have been performed without an ”a priori” knowledge a transition point inside bubble. Two tests are proposed. first test case considered bubble forming over flat plate subject adverse and then favourable pressure gradient. flow has studied experimentally by DNS at University Stuttgart. Spalart-Allmaras...

By adopting a proper slip length boundary condition in Large Eddy Simulations of airfoil flows at high Reynolds numbers it can be shown that riblets reduce both friction and form drag. We show induce small but significant modifications the pressure distribution which tends towards inviscid with improved recovery aft. A quantitative analysis using classical matched asymptotic expansion reveals layer displacement thickness. Reduced thickening equivalent body introduced by reduces drag leading...

Laminar separation bubbles are one of the main critical aspects flows at low Reynolds numbers in range . The flow separates laminar regime, turbulence developing inside recirculation region enhances momentum transport, and can reattach. Models based on Reynolds-averaged Navier–Stokes equations suffer two issues: determination transition onset level pressure recovery downstream reattachment flow. A model addressing both issues is presented this paper. It for detection. production turbulent...

The paper describes the numerical campaign carried out at CIRA for $1^{st}$ AIAA Ice Prediction Workshop (IPW). Some benchmarks have been selected with aim of assessing in-house capabilities different aspects ice-accretion chain. computed cases range from water droplet impingement to complete ice-accretions both in two- and three-dimensions. basic idea is coupling methodologies exploit their respective benefits towards prediction an in-flight ice-accretion. common recognized approach...

<div class="section abstract"><div class="htmlview paragraph">Future compliance to FAA 14 CFR Part 25 and EASA CS-25 Appendix O conditions has required icing wind tunnels expand their cloud simulation envelope, demonstrate accurate calibration of liquid water content droplet particle size distributions under these conditions. This led a renewed community interest in the accuracy calibrations, potential inter-facility bias due choice instrumentation processing methods. article...

<div class="section abstract"><div class="htmlview paragraph">This work presents the implementation and validation efforts of a 3D ice accretion solver for aeronautical applications, MESS3D, based on advanced Messinger model. The is designed to deal with both liquid phase crystal cloud conditions. In order extend model an algorithm water run-back distribution surface was implemented, in place air flow stagnation line search algorithm, which straightforward 2D but more complicated...

Abstract Purpose This paper aims to simulate unsteady flows with surfaces in relative motion using a multi-block structured flow solver. Design/methodology/approach A procedure for simulating was developed, based upon U-RANS solver1. Meshes produced zones of the field different rotation speed are connected by sliding boundaries. The developed guarantees that flux conservation properties original scheme maintained across boundaries during at every time step. Findings solver turns out be very...