Browsing by Author "Balaji, Rajoo."

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A mathematical model of marine diesel engine speed control system
(Journal of The Institution of Engineers (India): Series C, 2018-02) Sinha, Rajendra Prasad.; Balaji, Rajoo.
Diesel engine is inherently an unstable machine and requires a reliable control system to regulate its speed for safe and efficient operation. Also, the diesel engine may operate at fixed or variable speeds depending upon user’s needs and accordingly the speed control system should have essential features to fulfil these requirements. This paper proposes a mathematical model of a marine diesel engine speed control system with droop governing function. The mathematical model includes static and dynamic characteristics of the control loop components. Model of static characteristic of the rotating fly weights speed sensing element provides an insight into the speed droop features of the speed controller. Because of big size and large time delay, the turbo charged diesel engine is represented as a first order system or sometimes even simplified to a pure integrator with constant gain which is considered acceptable in control literature. The proposed model is mathematically less complex and quick to use for preliminary analysis of the diesel engine speed controller performance.
A review of developments in ballast water management
(Environmental Reviews, 2014-03) Balaji, Rajoo.; Yaakob, Omar.; Koh, Kho King.
Transportation and translocation of non-native species by ships through ballast water is one of the current issues the shipping industry is trying to address. The Ballast Water Convention is nearing full ratification after which treatment of ballast water will become mandatory for most of the trading merchant vessel categories. Ballast water management systems employing various technologies are commercially available but at high costs. Economics apart, the efficiency of these technologies and realistic ways to ensure compliance with stricter requirements of some Administrations are issues that need to be focussed upon. With the report of the Environmental Protection Agency as an assessment reference, this paper reviews the treatment technologies. Juxtaposing reports of Lloyd’s Register on the status, a concise overview of the technologies has been projected. A sustainable ballast water management based on data and assessments is proposed. The management must be extended to both shore and on-board platforms for practices, treatment, sampling, testing, and recycling. An exemplar system harvesting shipboard waste heat is projected as a route for thermal treatment in combination with technologies showing potential for optimized ballast water management
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.
An analysis of shipboard waste heat availability for ballast water treatment
(Journal of Marine Engineering & Technology, 2014-12) Balaji, Rajoo.; Yaakob, Omar.
Heat treatment of ballast water is one of the many treatment options being explored. This analysis has tried to assess the heat availability from the cooling water, exhaust gases of the engines and steam condensers based on design and operational data obtained from an existing crude oil carrier. Time requirements for ballasting and treatment using the seawater and condenser circulating pumps are projected. Heat balance exercises were also carried out on a testbed engine to verify attainable heat recoveries. It is seen that, although considerable heat is available, a longer time than that available during ballasting and normal ballast passages will be required for the treatment process.
Ballast water management triad: administration, ship owner and the seafarer
(International Journal of Environmental, Ecological, Geological and Mining Engineering, 2014) Balaji, Rajoo.; Yaakob, Omar.
The Ballast Water Convention requires less than 5% of the world tonnage for ratification. Consequently, ships will have to comply with the requirements. Compliance evaluation and enforcement will become mandatory. Ship owners have to invest in treatment systems and shipboard personnel have to operate them and ensure compliance. The monitoring and enforcement will be the responsibilities of the Administrations. Herein, a review of the current status of the Ballast Water Management and the issues faced by these are projected. Issues range from efficacy and economics of the treatment systems to sampling and testing. Health issues of chemical systems, paucity of data for decision support etc., are other issues. It is emphasized that management of ballast water must be extended to ashore and sustainable solutions must be researched upon. An exemplar treatment system based on ship’s waste heat is also suggested.
Comparision of heat exchanger design for ship ballast water heat treatment system
(Jurnal Teknologi, 2015-10) Balaji, Rajoo.; Yaakob, Omar.; Koh, Kho King.; Adnan, Faizul Amri bin.; Ismail, Nasrudin bin.; Ahmad, Badruzzaman bin.; Ismail, Mohd Arif bin.; Vern, Yiow Ru.
Sterilisation by heat can be a capital treatment for ballast water and waste heat from ship’s engines will be a good resource. Based on the waste heat availability on an operational tanker, a ballast water treatment system was envisaged including a shipboard heat exchanger for waste heat recovery. To verify the heat availability and the species’ mortalities, test rigs were arranged similar to shipboard arrangement. For assessing the smaller heat exchangers for the tests, designs were developed using Bell-Delaware approaches based on the shipboard heat exchanger design. The thermodynamic and geometric values were computed and the features of the commercially available and fitted heat exchangers were compared with the developed designs. Two commercially procured heat exchangers fitted on two separate engine test rigs were used for tests. The designs of commercially procured heat exchangers were close to the developed designs and were found to be suitable for the tests planned.
Design verification of heat exchanger for ballast water treatment
(Jurnal Teknologi, 2014) Balaji, Rajoo.; Yaakob, Omar.; Adnan, Faizul Amri bin.; Koh, Kho King.
Using waste heat from ship’s engines is one of the methods considered for heat treatment of ballast water. For such a system harvesting the engine exhaust heat, a heat exchanger will be vital. Design optimisation of a heater employing exhaust gases of the engine as utility fluid and ballast sea water as the process fluid was achieved using Lagrangian methods, keeping the annual cost as the objective function. Costs for installation, maintenance as also costs for the utility and process fluids were considered. Heat balance data, specific fuel consumption values from a typical operational ship and current fuel costs were considered for the design. The thermodynamic and geometric designs were worked out using computer based software for comparing the designs. Costs were also computed using a different approach for all the designs. Since the amount of heat transferred was specified and the application was limited to a single process, direct cost method was used for the computation. The objective function values obtained from Lagrangian equations were compared with the values obtained from direct cost computations. From the optimal designs, choice was justified based on annual cost, optimum exit temperature of shell side fluid and optimum mass flow of tube side fluid.
Developing a marine engineering centre of excellence for competency-based training
(WMU Journal of Maritime Affairs, 2017) Balaji, Rajoo.; Venkadasalam, Saravanan.
Institutes imparting training in marine engineering require replication of shipboard ambience for strengthening the competencies. For building an engineering centre for training, five options at different physical levels were considered based on a model of a new liquefied natural gas tanker ship build. A mock-up facility, simulator, full-scale engine room, scaled down version and a combination arrangement with live and dummy equipment were the options. Analytic hierarchy process was applied for selecting a suitable option based on criteria of cost, effectiveness in attaining competencies, practicability and environmental conduciveness. Analyses were carried out on the eigenvalues based on eight subselection criteria. The combination of live equipment (boilers and turbo alternator) and non-live shipboard equipment (auxiliaries) was chosen based on the global weightages obtained from the pairwise comparison matrix computations. The reliability was ascertained from the consistency index which was less than 0.1. For selection of the learning modes and the equipment, a constructivist approach of learners reflecting and choosing the learning mode was adopted. Industry practitioners were made into learner groups composed of trainers, shipboard personnel and company personnel. Established competencies were assigned as scores to the different learning modes. ANOVA application and statistical methods were used to analyse the scores to verify if there were too much variation in the choices. The calculated F ratio values were low (0.14 to 0.40) compared to the reference values indicating that the choices were even. The chi-squared test indicated that the group composition did have an influence on choosing the learning mode and equipment for training. The objective of identifying the learning mode and equipment for the training centre was achieved.
Emerging ballast water treatment technologies: a review
(Journal of Sustainability Science and Management, 2011-06) Balaji, Rajoo.; Yaakob, Omar.
Ballast water-shifts across the globe have been a major cause of ecological imbalance. The International Maritime Organisation (IMO) has actively taken regulated measures to minimise the species shift by adopting the International convention for the Control and Management of Ships’ Ballast Water and Sediments in 2004. Since then, vessels have been increasingly practising water exchanges. Exchanges are seen to be not completely effective. This regime has to give way for effective Ballast Water Treatment to keep up with IMO requirements as also the stricter requirements stipulated by some US ports. As full ratiication of the Treaty is pending, many treatment technologies have been emerging. A review of some representative systems is presented in this paper. Brief analyses of the systems available on date and those awaiting approval have been carried out. Most of these systems use a pre-treatment employing physical iltration and in the later part treat the ballast water with physical and chemical disinfection methods. An effective method for species reduction has been to employ chemicals. In terms of capital cost, foot print and power requirements, chemical solutions fare better than the physical disinfection methods. However, it is feared that chemicals might cause greater harm to the environment. Physical disinfection methods have lesser issues than the usage of chemicals. Considering the long-term harm of chemicals, a iltration system in combination with heat treatment is suggested. Such an attempt might even emerge as a viable option before the IMO deadline of 2016.
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.
How efficient are malaysian shipping companies: a stochastic frontier approach with malmquist productivity Indices
(Journal of the Institution of Engineers (India), Part MR: Marine Engineering Division, 2016-01) Venkadasalam, Saravanan.; Balaji, Rajoo.
The purpose of this paper is to analyse the performance of the Malaysian Shipping Companies. The company’s performance indicators such as technical efficiency and total factor productivity (TFP) have been measured using the stochastic frontier approach and subsequent Malmquist index. A secondary data for selected shipping and transportation service provider’s annual reports for the past five years were analysed using Frontier 4.1 and Data Envelopment Analysis Program (DEAP)software. It was found that 80% of the shipping companies were operating below the frontier line (<1.0). The findings are expected to contribute significantly to the business progress and performance metrics of Malaysian companies and also help to benchmark the shipping industry’s best practices.
Human factors as causes for shipboard oil pollution violations
(TRANSNAV International Journal on Marine Navigation and Safety of Sea Transportation, 2012-03) Saharuddin, A. H.; Osnin, A.; Balaji, Rajoo.
Shipping is a crucial transportation mode for world trade. Operation of ships has become a spe-cialisation. Maritime training addresses the needs and in doing so is heavily regulated. STCW lays down the requirements for such training and all training patterns in the world follow these. An important aspect of the training is the environmental factor. Ships use and carry large quantities of oils. This increases the potential for pollution. The laws and penalties on this front have increased and become stricter. This has decreased the operational pollution yet, there are violations occurring. The natures of violations are not only physical but al-so in documentation such as falsification of Oil Record Book entries etc. A study was undertaken to understand the effect of factors such as training, experience, attitude and fatigue on the oil pollution violations. The adequacy and effectiveness of current maritime training has been verified with reference to STCW and the recommended Lesson Plans of the IMO. Training apart, hypotheses on other human factors have been framed and tested by statistical methods. In this paper the human factors of experi-ence, attitude and fatigue are projected and the results are discussed. The various statistical methods such as ANOVA, Chi-square and correlation analyses have been applied as appropriate to the nature of the data ob-tained from the survey results. The survey conducted amongst seafaring officers formed the basis for the hy-potheses and the tests. Whereas training is found to be adequate, attitude and fatigue are shown to be the primary factors affecting oil pollution violations. Negligent attitude appears to diminish with increased experience but good attitude to-wards pollution prevention practices remain irrespective of the variation in experience or training. The factor of fatigue has a mention in many studies and the study validates the same. The concerns on this front are highlighted and recommendations for further probing into attitude-behaviour and fatigue are suggested. Mind-set behaviour training at management levels and pro-activeness of companies in overcoming some rea-sons for fatigue such as long working hours etc. are suggested. It is observed that attitude and fatigue could be the main causal factors which are resulting in pollution violations.
India’s blue economy priorities: maritime sector
(Current Science, 2024-01-25) Balaji, Rajoo.
Blue economy is an all-inclusive concept based on seas and shorelines. India has prioritized its blue economy policies, and maritime development (logistics, infra-structure and shipping) is one of them. For charting the nation’s growth, a regular review of global trends and India’s plans is imperative. The major drivers or focal areas will be decarbonization and digitalization. Increased costs due to transformations, including tech-nology acceptances and investments in port develop-ment to improve productivity will be on predictable paths. Shipping route alternatives (Northern Sea route, Belt and Road Initiative, etc.) will be in the discourses. Digitalization measures such as Maritime Single Win-dow, Port Community Systems, etc. will get traction. India needs to shift gears with its Sagarmala projects and keep pace with the global transformative changes, especially on the digital front. Based on its new National Logistics Policy, logistics costs as a large head need to be considered along with performance metrics. This article juxtaposes global trends and indices, and lists a few issues that India must address.
Oil pollution violations on vessels and adequacy of maritime training
(WMU Journal of Maritime Affairs, 2012) Balaji, Rajoo.
The paper projects the outcomes of an introspective study into the training imparted to the seafarer with respect to oil pollution matters. Typical training syllabi were compared with the prescribed lesson plans from Model Courses to verify quantitative and qualitative training. A sample has been drawn from the Malaysian and Indian seafaring officers for the study. Curriculum exposure to marine pollution regulations, and intensity and level of ship operational issues such as bypassing the separators and falsification of record books are analysed in the study. From the questionnaire survey amongst the officers, difficulties experienced in pollution prevention practices are highlighted. Statistical data analyses have been carried out to see if there is any relationship between pollution violations, training and human factors such as experience and attitude. While training appears to be sufficient, fatigue and attitude appear to be the causal factors for oil pollution violations. The paper concludes with suggestions for improving training such as simulator exercises and case study discussions, etc.
Optimisation of a waste heat exchanger for ballast water treatment
(Scientia Iranica B, 2015) Balaji, Rajoo.; Yaakob, Omar.
Ballast Water Treatment systems, which are type approved and commercially available, require improvements to meet stricter standards, and heat treatment could be a viable additional option. Considering the waste heat potential on a ship, a system harvesting the engine exhaust heat may be envisaged for which a heat exchanger could be vital. Design optimisation of a heater, employing the exhaust gases of an engine as utility fluid, and ballast sea water as the process fluid, was achieved using Lagrangian methods, keeping the annual cost as the objective function. Limiting the number of variables, optimal values were calculated with cost considerations for utility fluid and also pumping costs for utility and process fluids. In all, four optimum designs and three comparative designs were developed. Heat balance data from an operational tanker, specific fuel consumption values and fuel costs were considered for the design. The thermodynamic and geometric designs were worked out using computer based software for a comparison. Designs were compared on the basis of annual cost, optimum exit temperature of shell side fluid, optimum mass flow of tube side fluid and heat exchanger e ectiveness. It is demonstrated that an optimal heat exchanger design can be obtained with simple optimisation procedures.
Prediction of manoeuvring behaviour of an offshore supply vessel by using simulation program
(Proceedings of MARTEC 2010 The International Conference on Marine Technology, 2010-12) Mohd Noor, Che Wan.; Muzathik, Abdul Majeed.; Wan Nik, Wan Mohd Norsani.; Ahmad, Mohammad Fadhli.; Samo, Khalid.; Balaji, Rajoo.
Manoeuvring ability of Offshore Supply Vessel (OSV) is a very critical aspect. An early prediction of vessel behaviour will definitely help to improve upon the design. The regular methods available for manoeuvring prediction such as free running model test, captive model test etc., are found to be expensive and time consuming. As an alternative, the current approach tries a numerical simulation method with parameters determined from a database. This study presents the manoeuvring prediction of an OSV which includes the development of time domain simulation program by using Matlab Simulink software. Three degrees of freedom were considered and applying the Newtonian laws, the equations of motion were framed. Further, forces on hull, forces and moments induced by propeller and rudder were also taken into reckoning. Results were obtained with inputs of vessel speeds, engine revolutions etc. Validation of the prediction results was also carried out by comparing the results with full-scale sea trial data. The prediction results show a good agreement with the sea trial data. Applying approximate numerical formula for manoeuvring prediction is seen to be a reliable and economic prediction tool at early design stages of such vessels.
Redesign of an exhaust gas economiser using software
(Journal of The Institution of Engineers (India): Series C, 2014-09) Balaji, Rajoo.
Approaches to heat exchanger designs are numerous. Marine heat exchangers are usually single and they do not form part of a large network. Selections are generally based on the duties, area and the heat quantum. Over capacities and un-optimised designs could result. As an exercise to verify the choice, an existing heat exchanger on board of an operational ship was redesigned using computer software with thermodynamic data and standard geometric values. The formulae employed in the software were extracted and verified. The geometric data was used to develop the design drawings using SolidWorks . Visualising the designs, the physical arrangement was improved. Comparisons and design provements were made keeping the standard values in view. With the exercises, a method of developing an optimised physical design reducing the number of rating runs has been demonstrated.
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.
Voltage and frequency control of an asynchronous generator for a stand-alone wind energy conversion system
(Journal of Transport System Engineering, 2016) Balaji, Rajoo.
This paper proposes the voltage and frequency control for standalone wind energy conversion system, driven by isolated asynchronous generator with voltage source converter and battery energy storage system. The controller is a combination of voltage source converter made up of insulated gate bipolar junction transistor and battery storage system at the dc-link. Bidirectional active and reactive power flow capability of the controller function to ensure the voltage and frequency control of the system during variation in consumer load and wind turbine speed. The proposed system has been tested through MATLAB using Simulink.