Conference Proceedings
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Item Analysis of antifouling paints using drum test apparatus(RINA, 2015-12) Joshi, Madhu; Mukherjee, A.; Misra, S. C.; Ramesh, U. S.Ship has been recognized as a major factor in introduction of non-native and harmful organisms which causes deleterious effects on the performance of the vessel. More than 70% of Invasive species worldwide have found to be due to hull fouling. To mitigate fouling, underwater parts of the vessels are coated with antifouling paints. Antifouling paints provide foul-free hulls up to a maximum of 95 % of the vessels underwater area. There are a number of types of these paints but “self-polishing coatings” are predominantly preferred by the shipping industry. In these types of coatings, a thin layer of biocide containing paint (typically 2 to 5 microns/month) is leached or “polished” away. This polishing action primarily depends on the hydrodynamic surface forces on the vessels hull. The higher the fluid velocity, the higher are the polishing rate. Certain areas of the vessel such as near the bow, stern, etc experience higher fluid velocity and therefore higher polishing rates thereby resulting in premature fouling. Conversely, areas where the flow rates are considerably smaller would experience lesser polishing rates which would result in insufficient amount of biocides being delivered which would again result in premature fouling. In order to study and estimate the polishing rates of Anti Fouling paint we have designed, fabricated a rotating drum test facility .Wall shear stress are to be calculated by CFD methodsItem Natural biocides in antifouling paints(International Conference on Ship and Offshore Technology : Technological Innovations in Ship Building, 2013-12) Joshi, Madhu; Mukherjee, A.; Misra, S. C.; Ramesh, U. S.Since the 1970’s Tributy tin based antifouling (AF) paints were widely used to control fouling on ships hulls. These coatings offered up to 5 years of foul-free hulls and were the most effective antifouling paints ever produced. However, due to serious environmental effects, these paints have been banned since 2008 and have been replaced by copper based antifouling paints with some success. However, the extensive use of copper based antifouling paints has led to the accumulation of copper and its compounds in the marine environment particularly in the vicinity of ports and harbors and is beginning to pose a serious environmental problem. Restrictions on the use of copper based AF paints have been initiated by many western countries and it is expected that these restrictions would only grow in the years to come. In addition, these coatings are usually incorporated with “booster biocides” such as Diuron, Irgarol, Seanine, etc to improve their efficacy. The booster biocides also significantly contribute to the existing environmental concerns. The search is therefore on for a “benign AF product” that affects target organisms only and exhibits low persistence in the aquatic environment. A few natural produces fill in to these requirements. In the Indian context, Neem and Karanjin exhibit biocidal properties which could be tapped as effective AF agents. This paper reviews the various natural products that show promise as AF agents and explores the possibility of incorporating these products in AF paint formulation.Item Introduction to natural gas : A comparative study of storage, fuel costs and emissions for a harbor tug(SNAME Maritime Convention, 2013-11-08) Arun Kishore, Eswara; Misra, S. C.; Ramesh, U. S.This paper discusses the science of natural gas, its composition and ways to determine and coherently express its physical and chemical properties. Pricing of natural gas is shown with regard to weight and energy. A 60 Ton harbor tug employing either a set of constant rpm engines for CPP operation, or a set of variable rpm engines for FPP operation, with a standard load profile is made the basis for discussion. Advantage of evaluating thermal efficiency of gas engines relative to the higher heating value of natural gas, as against its lower heating value is explained. A compendium of storage options and the resulting endurance with the use of natural gas forms such as liquified gas (LNG), compressed gas (CNG) and adsorbed gas (ANG) is presented. Steps to ascertain fuel consumption of the gas engines operated according to the load profile and an approach to evaluate and relate the quantities of LNG, CNG and ANG is shown. Fuel costs and emissions from the tug operation using natural gas as fuel are evaluated per month and compared with diesel and residual fuels. Green House Gas emissions as a summation of emission constituents from the natural gas fuelled tug operation is detailed, and its need emphasized. The concepts of useful work done, emission efficiency parameter and energy efficiency parameter, which may be helpful in the design of harbor tugs and similar service vessels are proposed. The emission efficiency parameter is evaluated and analyzed for the 60 ton harbor tug.Item Feasibility study and design of shallow draught ore carriers for inland waterways(First International Conference IDS 2013, 2013-07) Sha, O. P.; Pallencar, S.; Viswanath, N.; Misra, S. C.The surge in iron ore exports from the Indian state of Goa has increased the demand for larger size inland iron ore carries. Operating economic of these inland vessels have resulted in a steady increase in their carrying capacity. However, attempt to increase the deadweight of these vessels has encountered challenges in form of loading and unloading point restrictions, increased squat, sway force and yaw moment at shallow waters. The present work based on a request from ministry of shipping, Government of India, examines the present ore transportation system, the bathymetry of the mandovi and zuari rivers and the operating economics of the barges ranging from 750 to 3000 tonnes deadweight capacity. A new improved design for 3000 tonnes dead weight barge is presented. Alternate stern shapes are examined using CFD software SHIPFLOW. The hull form is modal tested. The propeller geometry is optimized for the given engine and a suitable gear box. The proposed design is then investigated for its manoeuvring ability in shallow waters. The hydrodynamic sway forces yaw moments and nominal wake distribution for port and starboard propellers during manoeuvring motion are estimated by CFD software SHIPFLOW. The barge’s directional stability performance is investigated for twin-propeller twin –rudder configuration.Item Preliminary analysis for a circulating water channel using CFD(World Shipping Forum, 2013-02) Jaya Simha, B. Pradeep; Misra, S. C.; Gokarn, R. P.Sustainability in shipping includes improved designs that reduce power consumption. This requires advanced experimental techniques for hull form and propulsor development. A Circulating Water Channel (CWC) is used to generate a controlled flow environment and is used for various hydrodynamic research activities including flow around ships besides predicting its maneuvering behavior, studies for fishing nets, etc. While the experimental facilities such as towing tank facility, sea keeping and maneuvering basin are expensive, a relative low cost CWC, recognized by the ITTC community, is designed to facilitate academic and research activities and better flow studies. A preliminary Computational Fluid Dynamic analysis is carried out to minimize the variation of flow velocity through the guide vanes and across the width and study means of improving the flow uniformity in the test section of the CWC. A full scale CWC is modeled in commercially available software Altair Hyperworks 11.0 and a mesh is generated for the same. A CFD Analysis is carried out for 85°, 90°and 95° vane angles for an inlet velocity of 1.5 m/s. The results obtained are used to analyze and improve the flow uniformity in the test section of the CWC.Item Introduction to natural gas: A comparative study of its storage, fuel costs and emissions for a harbor tug(Society of Naval Architects & Marine Engineers, 2013-11-08) Eswara, Arun Kishore; Misra, S. C.; Ramesh, U. S.This paper discusses the science of natural gas, its composition and ways to determine and coherently express its physical and chemical properties. Pricing of natural gas is shown with regard to weight and energy. A 60 Ton harbor tug employing either a set of constant rpm engines for CPP operation, or a set of variable rpm engines for FPP operation, with a standard load profile is made the basis for discussion. Advantage of evaluating thermal efficiency of gas engines relative to the higher heating value of natural gas, as against its lower heating value is explained. A compendium of storage options and the resulting endurance with the use of natural gas forms such as liquified gas (LNG), compressed gas (CNG) and adsorbed gas (ANG) is presented. Steps to ascertain fuel consumption of the gas engines operated according to the load profile and an approach to evaluate and relate the quantities of LNG, CNG and ANG is shown. Fuel costs and emissions from the tug operation using natural gas as fuel are evaluated per month and compared with diesel and residual fuels. Green House Gas emissions as a summation of emission constituents from the natural gas fuelled tug operation is detailed, and its need emphasized. The concepts of useful work done, emission efficiency parameter and energy efficiency parameter, which may be helpful in the design of harbor tugs and similar service vessels are proposed. The emission efficiency parameter is evaluated and analyzed for the 60 ton harbor tug.Item Control of bio corrosion to prevent the propagation of invasive species(National Corrosion Council of India (NCCI), 2010-09-16) Madhu, Joshi; Mukherjee, A.; Misra, S. C.; Ramesh, U. S.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 Anifouling paint schemes to minimize the risk of transmigration of invasive species(Sixteenth National Congress on Corrosion Control, 2012-08) Mukherjee, A.; Joshi, Madhu; Misra, S. C.; Ramesh, U. S.Biocorrosion or biofouling on ships hull occurs 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 enough to prevent the transport or invasion of alien species which result in numerous environmental issues that include reduction and extinction of native species and thereby seriously disrupting the natural ecosystems. Virtually all ocean going vessels are coated with antifouling paints, predominant among them are “Self polishing coatings” and “Foul Release Coatings”. Both these coatings depend on hull shear forces caused by the motion of the vessel, by different mechanisms, to result in the hull to be essentially foul-free. Currently hulls are coated with a uniform layer of antifouling paints. However, CFD analysis conducted on various types of vessels have shown highly non-uniform wall stress distribution along the vessels hull. This results in premature paint failure for “Self polishing Coatings” and insufficient shear forces for “Foul release coatings” to release the attached fouling organisms. Both these factors contribute significantly to the transmigration of invasive species. Preliminary results of the current work indicate that certain areas of the vessel such as such as bow thrusters, sea chest, stern tube, rudder etc. are the likely areas to be heavily fouled thereby warranting special attention in such areas. Solutions to these issues include alternative paint schemes/formulations in the identified niche areas to account for non-uniform shear and polishing of paints. Such schemes would ultimately reduce the risk of transmigration of invasive speciesItem A new era of maritime education(INMARCO, 2011-12) Misra, S. C.Imparting quality education is an ongoing process and the role of good faculty and infrastructure facilities cannot be undermined. IMU is making efforts to give a new direction and set academic standards in imparting quality maritime education. For this to happen, the need for academic programs supported by strong values of research is felt like never before. IMU must set forth an example in this direction.Item Bio diesel as an alternative fuel for maritime transport(Indian Maritime University, 2011-09-30) Misra, S. C.; Ramesh, U. S.Movement of goods through seaways and rivers is one of the most energy efficient modes of transportation. Majority of the ships and boats in maritime transportation use Diesel engines for propulsion and power requirements burning a variety of grades of fossil fuel. However with the advent of the concept of sustainable environment, this industry is also looking towards improving its energy efficiently and environment friendliness. This paper outlines the regulatory requirements for fuels and emissions from diesel engines from ships operating in international trade. While Bio Diesel is one of the alternatives for reduction of maritime emissions due to its very low or negligible sulphur content and amenability to complete combustion, its testing in a marine environment in India is limited. The paper gives an overview of some of the results of studies conducted internationally on the use of Bio Diesels in marine transportation. An estimate of requirement of biodiesel for Coastal shipping in India is presented. The paper stresses the need for increased testing of Biodiesel blends in marine engines to quantify the benefits and cost implications for use in coastal and river movement of cargo and passengers.