Comparative Study on the Performance of Lampara Dasar (Indonesian Traditional Bottom Trawls)

Accession number;06A0185547
Title;Comparative Study on the Performance of Lampara Dasar (Indonesian Traditional Bottom Trawls)
Author; AHMADI (Kagoshima Univ., Kagoshima, Jpn) FUWA SHIGERU (Kagoshima Univ., Kagoshima, Jpn) EBATA KEIGO (Kagoshima Univ., Kagoshima, Jpn) BUDIMAN JOHNNY (Kagoshima Univ., Kagoshima, Jpn)
Journal Title;Memoirs of Faculty of Fisheries, Kagoshima University
Journal Code:F0747A
ISSN:0453-087X
VOL.54;NO.;PAGE.45-56(2005)
Figure&Table&Reference;FIG.14, TBL.7, REF.10
Pub. Country;Japan
Language;English
Abstract;Two 1/8 scale models of "Lampara Dasar", typical for the commercially used bottom trawls in Kotabaru of Indonesia, were selected and tested in a flume tank. They were to represent prototypes of two large trawls i.e. Type A, bottom trawl with a low engine power of 20 HP at a towing speed of 2 knots, and Type B, bottom trawl with a high engine power of 33 HP at a towing speed of 3 knots. They were composed of 2-seam panels with the same dimension and materials, however, gear construction and trawling conditions were different. The study was aimed to obtain some fundamental data of gear efficiency based on the physical characteristic and performance of trawls under different towing conditions. Results showed that in ordinary towing conditions (wing tips distance expands to be 53%), the net height of Type A was higher than that of Type B for both towing conditions. Similar conditions were also indicated in the projective area of net mouth and water filtering volume. Gear efficiency was measured by the ratio of net height to the net circumference. At a towing speed of 2 knots, the initial net height of Type A was 5.5% of net circumference and that of Type B was 4.8%. At a towing speed of 3 knots, Type A was 4.1% of net circumference and Type B was 3.4%. The ratio of Type A was considerably higher than that of Type B in all experimental conditions because it has a square part in the gear construction, and the net circumference was larger than that of Type B. Total net resistance of Type B was larger than that of Type A in both towing conditions. (author abst.)