- Identification: 103/94/1186 - Grant Agency of the Czech Republic
- Duration: 1994 - 1996
- Principal investigator: Prof. Ing. Jaroslav Pollert DrSc. (Faculty of Civil Engineering CTU)
- Co-investigator: Ing. Zdeněk Chára CSc.
The phenomenon of drag reduction by means of synthetic additives can be achieved by the addition of small amounts of drag reducing additives to the system. High polymer drag reducing additives have received a great deal of attention in recent years. Theirs use are not in some cases feasible due to irreversible degradation in regions of high shear. This important disadvantage is possible nowadays to overcome by soluble surfactant additives of micellullar type (PA) but theirs fluid flow conditions are not well known yet. Some of them reach 80 % drag reduction and are "repairable", i.e. they demonstrate reversible shear degradation what is for utilisation in circulation pipe loops advantageous. Any groups of surfactant additives are also resistant to higher temperatures and thus their use in heating networks is promising. Using PA drag reducing additives in circulation pipeline networks can increase the energy capacity of the system and/or reducing the operating power costs or the capital costs of pipes, fittings, etc. Experimental investigations should be pointed to fluid flow of PA drag reducing additives under different boundary conditions and temperature levels in single and complicated branched pipe systems from point of view of structure and turbulence, drag reducing efficiency and scale-up effects.
