DEVELOPMENT OF AN EXPERT SYSTEM FOR CONDITION MONITORING OF SUBMARINES USING IR THERMOGRAPHY

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1 International Journal of Mechanical Engineering and Technology (IJMET) Volume 8, Issue 4, April 2017, pp Article ID: IJMET_08_04_004 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed DEVELOPMENT OF AN EXPERT SYSTEM FOR CONDITION MONITORING OF SUBMARINES USING IR THERMOGRAPHY Mojeswara Rao Duduku, Kavuluri Lakshmi Narayana, Kavuluri Venkata Ramana and Mechanical Engineering, K L University, Vaddeswaram, , India ABSTRACT Infrared thermography has become an accepted and widely used technique for condition monitoring wherein Knowledge of surface temperature of an object is utilized for gaining information regarding its working condition. In its present form, IR Thermography has evolved from the broader area of thermal testing which involves the Temperature or heat flow in a body, machine or system. The aim of such an exercise is to know about the status, Functioning or condition of the body involved. This has gained increasing significance with the advent of the Industrial age and has evolved into the technology of condition monitoring and non-destructive testing in industrial maintenance. Expert systems are computer systems that emulate the reasoning of a human expert. The advantage of expert system is cost effective and independent of the exit of the plant expert and analyzes the data quickly and efficiently. In this paper an expert system has been developed using JAVA, for condition monitoring of submarine systems. By giving the measured temperature values using IR camera as input to the expert system one can easily conclude whether the system is safe or unsafe. Further, a few systems of submarines fault diagnosis and remedial measures have been suggested. Key words: Condition Monitoring, IR Thermography, Expert Systems, Submarines. Cite this Article: Mojeswara Rao Duduku, Kavuluri Lakshmi Narayana, Kavuluri Venkata Ramana and, Development of an Expert System for Condition Monitoring of Submarines Using IR Thermography, International Journal of Mechanical Engineering and Technology, 8(4), 2017, pp INTRODUCTION Infrared imaging and radiometry in industrial and commercial sectors have been available since the mid-1960s. There has been an increase in the number and types of equipment available and more importantly, an increase in the use and applications for the technique. The thermal behavior of electrical, mechanical or process equipment can be a powerful clue to diagnose problems and predict reliability of industrial equipment editor@iaeme.com

2 Mojeswara Rao Duduku, Kavuluri Lakshmi Narayana, Kavuluri Venkata Ramana and An infrared camera produces an infrared image or thermogram. It displays the thermal radiation emitted from the surface of the objects based on their temperatures. The standard image is a greytone image that shows hot objects as white descending in greytones until black is reached, which is the coolest temperature of the surface under investigation. When appropriate, one can colorize the image. Yellows and reds usually depict hotter objects and violet and blue shades show cooler items. In 2004, Loyd s Register, the world s most important ship classification and certification body, made the prediction that In the near future, mechanical machinery of marine vessels will also benefit from thermal imaging, especially as a pre-docking strategy to identify and target equipment and systems which need attention as well as to eliminate necessary work. IR thermography has the advantage of being an inspection and measurement tool able to display and store exact temperature values as well as visual evidence IR Thermography offers the advantage of not interfering with the vessel s operation. Engines must work at their normal loads and temperatures for good conditions. A three to four hour trip at full speed and in full load condition is ideal to get a clear picture of the submarine s electrical and mechanical systems. Thermography finds its largest marine application on cargo ships. Typical applications of thermography on cargo ships are not entirely different from those on land-based facilities. When it comes to cargo surveys, if there are differences in surface temperatures, a trained operator can interpret thermal patterns [1]. The largest marine application serviced by thermography is submarines. A few of the typical systems regularly serviced are Re-heaters, moisture separators, feed water pump, HP turbine, Inlet valves, Compressors, pumps, pulleys,belts, condenser seal, pressure and vacuum leaks, condensate pumps, vacuum pumps, couplings, bearings, gears, gear boxes, hydraulic systems, internal combustion engines, turbines[2]. One of the biggest differences when performing thermography on any type or size of marine vessel is space of operation. As one can imagine, in any submarine, space is limited and at a premium. Many times when trying to perform a survey on any type of submarine, the target is too close to machinery or other structures to achieve a good focus or resolution. For this reason, wide-angle lenses are often required, with a little ingenuity and dexterity in order to perform a quality job [3]. Thermography can play a crucial function in maintaining the safety and reliability of marine facilities where system failure could lead to catastrophic loss of a vessel or its crew. Another application serviced by marine thermograph is dredge boats, simply known as dredges [4]. 2. EXPERT SYSTEM Expert systems are computer programs that perform human like reasoning, thus automating and reasoning process. They typically use chains of if-then decision rules to automate decision making. Expert systems codify human knowledge in a form that can be executed on a computer. The rapidly spreading use of expert system technology and the availability of programming tools make the development of expert applications highly efficient, particularly for condition monitoring application. Expert systems allow capture of human knowledge in near English rules collectively called a knowledge base. The block diagram of an expert system is shown in figure editor@iaeme.com

3 Development of An Expert System For Condition Monitoring of Submarines Using IR Thermography Figure 1 Block diagram of expert system. An expert system has been developed in Java making it user friendly. The data bank has been compiled including different standards of oils such as Society of Automobile Engineers (SAE), International Organization for Standardization (ISO), American Gear Manufacturers Association (AGMA), and National Lubricating Grease Institute (NLGI) for different grades of oils. The flow chart of the expert system has been presented in figure editor@iaeme.com

4 Mojeswara Rao Duduku, Kavuluri Lakshmi Narayana, Kavuluri Venkata Ramana and Figure 2 Flowchart of the expert system. The expert system will give out an indication whether the surface is well within the stipulated temperature limit or not. If the expert system gives an unsafe condition in terms of measured temperatures it can be concluded that the component under investigation is not functioning properly due to fault / faults. The expert system is also included with direction of temperature measurement using IR camera. 3. VALIDATION The expert system that is developed has been validated using thermal imager as shown in Figure.3 which can measure temperatures in the range of -20ºC to +600ºC 29 editor@iaeme.com

5 Development of An Expert System For Condition Monitoring of Submarines Using IR Thermography Figure 3 IR Camera Table 1 A summary of validation of expert system is presented S.No Component Conclusion 1 Diesel engine Safe 2 Motors Safe 3 Clutches Unsafe 4 Gear system Safe 5 Pump Safe 6 Air compressor Safe 7 Bearings Unsafe 8 Turbine Safe 9 Generator Safe 10 Condenser Safe A few case studies have been presented in figures 4, 5, and editor@iaeme.com

6 Mojeswara Rao Duduku, Kavuluri Lakshmi Narayana, Kavuluri Venkata Ramana and Figure 4 Motor diagnosis. Figure 5 Air Compressor diagnosis editor@iaeme.com

7 Development of An Expert System For Condition Monitoring of Submarines Using IR Thermography Figure 6 Bearing diagnosis. 4. FAULT DIAGNOSIS The expert system clearly reflects that Motor and Air compressor are under safe temperature limits whereas the bearing is radiating energy above the safe limit. It is recommended to check for bearing misalignment / heat from seals / insufficient lubrication 5. CONCLUSION In this paper an attempt has been made to develop the expert system based on IR thermography to monitor the condition of various systems in a submarine. The expert system has been validated with the experimental values. It is observed that clutches and bearings are dissipating more radiation and other systems under investigation are safe. REFERENCES [1] Infrared Thermography in Marine applications, [2] Finestum: IR Thermography in marine applications Dated:-28 December 2014, [3] Infrared Thermography in Marine Industry, [4] Thermography for marine surveying, [5] Arka Sen, Manik Chandra Majumder, Sumit Mukhopadhyay and Robin Kumar Biswas, (2017) Multi Attribute Decision Making in Selection of the Most Significant Condition Monitoring Methodology for Rotating Machinery. International Journal of Mechanical Engineering and Technology, 8(3), 2017, pp editor@iaeme.com

8 Mojeswara Rao Duduku, Kavuluri Lakshmi Narayana, Kavuluri Venkata Ramana and [6] L.B. Bhuyar, S.V. Kshirsagar, G.K. Awari and A.S. Padalkar,(2010) Fault Detection And Condition Monitoring Of Machine-Structure: Review, International Journal of Mechanical Engineering and Technology, 1(1), pp [7] R. S. Hingole and V. M. Nandedkar, The Need of Expert System For Forming Analysis of Extrusion Process, International Journal of Mechanical Engineering and Technology, 1(1), pp