Research Publications
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Item Development of a ballast free ship design(International Journal of Innovation Research & Development, 2012-12) Godey, Avinash; Misra, S. C.; Sha, O. P.Shipping transfers approximately 3 to 5 billion tonnes of ballast water internationally each year. Ballast water discharges non-native species leading to severe ecological problems. The present work aims at a design solution into the ballastless ship in which ballast water exchange and treatment is avoided by providing flow-through longitudinal pipes in the double bottom instead of conventional ballast tanks. During the design of the ballast less ship, different hull forms are generated with altering the hull shape in forward and aft out of which one was finalised. In addition to change in hull form the internal tank arrangement has been changed so that the propeller immersion and the minimum draft required in the ballast condition is achieved. Structural arrangement for the mid ship section was proposed for the modified hull form of ballast less ship as well as data on valves had been collected for the flow through condition. Finally, resistance tests were conducted on equivalent models of scale ratio 1:71 for the conventional and the proposed ballsatless form at the loaded and ballast drafts in the Hydrodynamic Towing Tank of the Department of Ocean Engineering and Naval Architecture, IIT Kharagpur. The model experiments on ballast less ship show an increase in resistance in ballast draft when compared to a conventional tanker due to the flow through pipes in double bottom.Item Validation of engine performance for tests on ballast water heat treatment using engine waste heat(International Journal of Marine Engineering Innovation and Research, 2017-12) Balaji, Rajoo.; Yaakob, Omar.; Koh, Kho King.; Adnan, Faizul Amri bin.; Ismail, Nasrudin bin.; Ahmad, Badruzzaman bin.; Ismail, Mohd Arif bin.Heat treatment has been considered as a suitable option for treatment of ballast water. Utilising the waste heat from the diesel engine fresh water and exhaust gases would be an economic option. For recovering the heat from the exhaust gases, heat exchangers are required to be placed in their flow path. The sea water coolant after recovering heat from fresh water has to be directed to this heat exchanger for sterilisation. For testing the effectiveness of these heat recoveries on species’ mortalities, a mini-scale system was arranged and tests were carried out. The engine output and other flow rates were maintained to achieve a temperature range of 55 to 80oC. Data was obtained from the sensors and probes fitted at relevant points. The engine performance was monitored with computerised control equipment. Operational data from five test runs were analysed and verified by two approaches. In the first approach, the heat recovered by the water was compared with the heat lost by the exhaust gases and the maximum variation was observed to be 3.4%. In the second approach, the input energies were computed using two different methods using data values of brake power, thermal efficiency, mass flows, calorific value and specific fuel consumption. A maximum variation of -11% was seen for only one test run, while for other tests the variation was between -0.7% to -1.7%. The values obtained from the connected probes and the computed results were thus validated and further tests on species were carried out.Item Exergy analysis of a medium size LNG tanker steam power plant(Annual technical volume, Marine engineering division board, 2016) Sinha, Rajendra Prasad.; Balaji, Rajoo.Exergy is the maximum work which can be obtained from a quantity of heat Q at temperature T1 received by a system interfacing with a surrounding environment at temperature T0. In other words from the received heat energy ‘Q’ a small portion fails to convert into useful mechanical work and is thus lost which we call exergy destroyed. The loss of exergy in this heat work exchange process lowers overall thermal efficiency of the plant. Exergy destruction is actually the result of irreversibility in various processes of the plant and can be estimated from the second law of thermodynamics as the product of ambient temperature T0 and the positive entropy change Δsi.e. (T0Δs). The common irreversibility which cause entropy rise are mechanical or hydraulic friction, heat transfer with a finite temperature difference and diffusion with a high gradient of concentration etc., as most of these are present in a physical plant. Exergy analysis gives an insight into the way energy flows in the system and helps to locate components of the plant with high irreversibility to effect design improvements. In this paper the authors conduct energy and exergy analysis of 30 MW dual fuel fired marine steam power plant of a typical medium capacity LNG tanker and identify components responsible for major exergy destruction. Effects of steam reheating to reduce irreversibility and potential utilization of the cold energy of boil off gas in the thermodynamic cycle has been studied with the result showing 2-4 % improvement in the overall exergy efficiency of the plant.Item A study of ballast water treatment using engine waste heat(Journal of The Institution of Engineers (India): Series C, 2019-04) Balaji, Rajoo.; Yaakob, Omar.; Koh, Kho King.; Adnan, Faizul Amri bin.; Ismail, Nasrudin bin.; Ahmad, Badruzzaman bin.; Ismail, Mohd Arif bin.Heat treatment of ballast water using engine waste heat can be an advantageous option complementing any proven technology. A treatment system was envisaged based on the ballast system of an existing, operational crude carrier. It was found that the available waste heat could raise the temperatures by 25 C and voyage time requirements were found to be considerable between 7 and 12 days to heat the high volumes of ballast water. Further, a heat recovery of 14–33% of input energies from exhaust gases was recorded while using a test rig arrangement representing a shipboard arrangement. With laboratory level tests at temperature ranges of around 55–75 C, almost complete species mortalities for representative phytoplankton, zooplankton and bacteria were observed while the time for exposure varied from 15 to 60 s. Based on the heat availability analyses for harvesting heat from the engine exhaust gases(vessel and test rig), heat exchanger designs were developed and optimized using Lagrangian method applying Bell–Delaware approaches. Heat exchanger designs were developed to suit test rig engines also. Based on these designs, heat exchanger and other equipment were procured and erected. The species’ mortalities were tested in this mini-scale arrangement resembling the shipboard arrangement. The mortalities realized were[95% with heat from jacket fresh water and exhaust gases alone. The viability of the system was thus validated.Item Control of biocorrosion to prevent the propagation of invasive species(Indian Maritime University, Chennai, 2010-09) Joshi, Madhu; Mukherjee, A.; Ramesh, U. S.; Misra, S. C.Biocorrosion or biofouling on ships hull occursdue to the attachment of barnacles, mollusks and other aquatic organisms on the surface of ships which leads to increase in fuel consumption, reduction of the vessels speed, premature failure of the hull, etc. Recent developments in antifouling paints, in general, prevent fouling in about 95% percent of the vessels underwater surface, which ship operators find satisfactory as far as the routine vessel operation is concerned. However, this is not sufficient to prevent the transport or invasion of alien species. In recent years the issue of invasive marine species has been receiving considerable attention due to the fact that introduction of nonidegenous species or non-native species transmigrated from other areas to coastal waters often results in the reduction and even extinction of the native species and thereby severely disrupting the natural marine ecosystems. The predominant vector for the transport of nonindigenous species in marine environments has been shipping. While ballast water receives the most attention, hull fouling is now considered to be the most significant means for translocation of these organisms. For example, 90 percent of the 343 marine alien species in Hawaii are thought to have arrived through hull fouling Certain niche areas of the vessel such as bow thrusters, sea chest, stern tube, rudder etc. are the likely areas to be heavily fouled. In addition, the other areas that are likely to be fouled are on locations where antifouling paint has been worn of due to excessive shear and bending of the hull. This paper reviews the various antifouling strategies and aims identify areas on the hull surfaces of certain classes of vessels that are prone to fouling by excessive shear and bending and identify suitable antifouling treatments to further reduce the risk of transportation of alien species.Item Control of biocorrosion to prevent the propagation of invasive species(Indian Maritime University, Chennai, 2010-09) Joshi, Madhu; Mukherjee, A.; Ramesh, U. S.; Misra, S. C.Biocorrosion or biofouling on ships hull occursdue to the attachment of barnacles, mollusks and other aquatic organisms on the surface of ships which leads to increase in fuel consumption, reduction of the vessels speed, premature failure of the hull, etc. Recent developments in antifouling paints, in general, prevent fouling in about 95% percent of the vessels underwater surface, which ship operators find satisfactory as far as the routine vessel operation is concerned. However, this is not sufficient to prevent the transport or invasion of alien species. In recent years the issue of invasive marine species has been receiving considerable attention due to the fact that introduction of nonidegenous species or non-native species transmigrated from other areas to coastal waters often results in the reduction and even extinction of the native species and thereby severely disrupting the natural marine ecosystems. The predominant vector for the transport of nonindigenous species in marine environments has been shipping. While ballast water receives the most attention, hull fouling is now considered to be the most significant means for translocation of these organisms. For example, 90 percent of the 343 marine alien species in Hawaii are thought to have arrived through hull fouling Certain niche areas of the vessel such as bow thrusters, sea chest, stern tube, rudder etc. are the likely areas to be heavily fouled. In addition, the other areas that are likely to be fouled are on locations where antifouling paint has been worn of due to excessive shear and bending of the hull. This paper reviews the various antifouling strategies and aims identify areas on the hull surfaces of certain classes of vessels that are prone to fouling by excessive shear and bending and identify suitable antifouling treatments to further reduce the risk of transportation of alien species.