BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI - Universitatea ...

BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI
Publicat de
Universitatea Tehnică „Gheorghe Asachi” din Iaşi
Tomul LVI (LX), Fasc. 2, 2010
Secţia
CONSTRUCŢII DE MAŞINI
MODELING 3D SURFACE OF TEXTILE STRUCTURES
FOR FLUID FLOW IMPROVEMENT
BY
CĂTĂLIN DUMITRAȘ 1 , CARMEN LOGHIN 1 , SULEYMAN YALDIZ 2 ,
MEHMET SAHIN 2 and LUMINIȚA CIOBANU 1
Abstract. The efficiency of thermal insulation in a windy environment can be
increased by using adequate protective equipment. Following a FEA analysis
regarding the flow of fluids (air) at body surface, the presence of critical zones
with turbulences was detected. The critical zones are the ones with a change in
geometry, such as the shoulders, hips or hands. This generates the idea that
something has to be done to improve the fluid flow at surface level of the exterior
garment layer. The main problem is to ensure a certain path for the fluid
movement, so that the flow will become laminar. A simple and feasible solution is
creating a textile structure with an architecture that includes these paths. Different
variants of 3D geometries are proposed. Their dynamic behaviour is studied in
order to rank the proposed fabricse abstract of the paper is to be written here. It
contains the main ideas and original contributions and conclusions of the authors’
research.
Key words: laminar air flow, weft knitted fabrics with relief effects, sandwich
fabrics, FEA, meshed models, fluid flow.
1. Introduction
The problem of thermal protection in hostile environments is certainly not
new, but it does not loose its interest due to the fact that there are large range of
activities requiring such protective equipment, from winter and extreme sports,
cycling, motorcycling to working in harsh winter conditions. There are a lot of
studies regarding developments of textile fabrics and materials to improve
thermal insulation. Still, the fluid flow around the garments in dynamic
conditions is less investigated and the problem of designing textile structures
with improved behaviour in relation to air flow remains open to debate.