Abstract

Biofouling of ships’ internal seawater systems (ISS) can cause significant operational issues and is a potential transfer mechanism for marine nonindigenous species. This study used an engine room simulator and economic evaluation to quantify impacts on commercial ship performance of biofouling occlusion within various ISS nodes (sea chest, strainer, and heat exchangers). A characteristic hockey-stick relationship between occlusion and impact emerged, whereby engine room systems could tolerate up to 55% occlusion of a single node without operational impact, followed by rapid performance deterioration. The relative magnitude of impacts varied by ISS node and in response to changes in ambient seawater temperatures. System tolerance was much lower when simultaneous occlusion of multiple nodes was assessed. In economic terms, consequences included required freight rate increases of 1–26% prior to forced (automatic) slowdown of the ship and up to 82% increases if slowdown conditions were required.

摘要

船舶内部海水系统（ISS）的生物污垢可能会导致严重的操作问题，并且是海洋非本地物种的潜在转移机制。本研究使用机舱模拟器和经济评估来量化各种国际空间站节点（海底箱、过滤器和热交换器）内生物污垢闭塞对商业船舶性能的影响。遮挡和影响之间出现了一种典型的曲棍球棒关系，机舱系统可以容忍单个节点高达 55% 的遮挡，而不会影响运行，随后性能会迅速恶化。影响的相对程度因国际空间站节点的不同以及周围海水温度的变化而异。当评估多个节点同时闭塞时，系统耐受性要低得多。从经济角度来说，