Scope and Objectives

1. Preparation and investigation of rheological properties of cost effective in-house MR fluid under different magnetic field and benchmark with commercial MR fluid.
2. Design, development and characterization of market ready cost effective in-house MR damper for two and four wheelers automobile.
3. Comparison of dynamic behavior of in-house MR damper with commercial MR damper.
4. Performance evaluation of passive damper, in-house MR damper and commercial MR damper with standard excitation in laboratory.
5. Analytical and experimental analysis to compare ride comfort and road holding analysis of vehicle having passive damper, in-house MR damper and commercial MR damper on road.

Deliverables

On completion of the proposed project, following are the deliverables and outcome.
1. Technology development of low cost in-house MR-Fluid and in-house MR-Damper development with a better performance in terms of ride comfort and stability of an automobile.
2. Research findings will be published in reputed international journals and conferences.
3. Patents will be filed based on new product development.
4. Ph.D and M.Tech thesis work based on proposed project.
5. Consolidated report will be prepared and submitted.
6. Based on the project final results, there is an additional scope of following. i. Possibility of proposed technology can be adopted to fabricate MR Dampers in large scale by leading suspension makers (such as Rambal India Ltd.) ii. Based on project findings, leading vehicle makers can introduce a vehicle with smart suspensions to Indian Market

Videos

Scientific Output

1. As per the objective listed, it was one of the criteria to produce MR fluid which can compete economically with commercially available MR fluid. This objective has been significantly fulfilled with a few characterization tests pending to achieve complete success. The prepared MR fluid has showed good characteristics in terms of shear stress, viscosity, settling time of particles to achieve expected damping force. Also, it is intended to carry out further studies to improve the magnetic property, settling time of the iron particles.
2. Major testing facilities have been created at NITK to test MR dampers which are designed at NITK. Also, a testing facility named Quarter car suspension test rig has been installed which enables testing of entire suspension system including damper of a four wheeler vehicle. This facility creation is a major milestone in testing of suspension system to understand the vehicle stability and ride comfort.
3. It is necessary to understand the road condition for which suspension system is to be tested. Hence, to test a suspension system through quarter car test rig, input will be given as spectrum of a road profile. Measurement of the road profile, through a third party is not economical. Hence, a customized road profile measurement instrument has been developed at NITK, which can measure any road profile with required precision.
4. MR fluid changes its characteristics upon changing the magnetic flux around it. Magnetic flux can be varied with supply of electric current through wires wound around the piston. This DC power supply can be varied through a current controller. With an aim to develop an economic and effective control device, a current controller is being developed at NITK.
5. To understand the behavior of a damper with MR fluid, it is necessary to design and fabricate an MR damper. In collaboration with an industry, Arya technocrats, Belgaum, Karnataka, different types of MR dampers such as flow mode, shear mode and mixed mode dampers have been fabricated and tested. In the later stages, it is intended to alter already designed MR damper so that it can be made suitable for use in two wheeler and four wheelers.
6. With the help of Rambal Ltd., Chennai, an industrial collaborator for this project, an MR damper suitable for tempo traveler has been designed and fabricated. The recent test results are closer to the characteristics of commercially available MR damper. In India, there is no availability of MR dampers with customized design and the results obtained with in house prepared MR damper is a major progress towards future availability of MR damper for passenger vehicles in India.

Results and outcome till date

1. Inhouse developed MR fluid has shown promising results in rheology experiments. Properties like field dependent yield stress, viscosity and shear rate curves are nearly same as that of commercially available MR fluids.
2. Sedimentation studies of MR fluid involving Coated and uncoated carbonyl iron particles showed improved resistance to sedimentation. Also carrier fluid having higher kinematic viscosity showed better performance during sedimentation studies.
3. MR damper prototype has been designed and manufactured in collaboration with industrial partner Rambal Ltd., Chennai. Performance testing of the MR damper is in progress.
4. Design of a current controller for MR damper has been done and prototype current controller has been developed.
5. Research findings have been published in three international journal publication and four international conference publication.
6. Two patents related to the research findings have been filed in Indian patent office.
7. One Ph.D. thesis with title "Characterization of Magnetorheological fluid and Monotube MR Damper through experimental and computational methods" has been submitted on 3rd May 2018 under IMPRINT project.

Societal benefit and impact anticipated

1. Users of passenger automobiles fitted with MR dampers will have better ride comfort and stability thereby providing safe transportation.
2. If vehicles are fitted with MR dampers, shocks generated due to vehicles travelling over road irregularities will be attenuated. This will prevent damage to both the vehicles and the road they are travelling upon. Since the vehicles and roads both will protected from damage, they will be in better condition for longer time.
3. Semi-active suspension technology based on MR dampers is only available in luxury car brands such as Audi, Ferrari, Chevrolet, Porsche, Lamborghini and Land Rover which are very expensive. Reducing the cost of the MR dampers under IMPRINT project will help in introducing this technology to the larger public in India.
4. Manpower in terms of SRF and JRF have been appointed under the project. They will be trained in technical know how related to MR dampers.

Next steps

1. The Discrete element method will be combined with the experimental investigation to understand the processes involving the particles.
2. Sedimentation study is conducted to reduce the sedimentation between the particles, Viscosity of the carrier fluid should be less and the density of the particle should decrease so that the particles can disperse easily.
3. Leakage issues will be addressed. The damper piston designs are being modified so as to stop leakage through the piston rod.
4. Mathematical modelling of prototype damper based on the experimentally obtained results.
5. Heat generated under normal operation of MR Damper will be studied analytically using commercial software and also experimentally analyzed.

Publications and reports

1. Tharehalli Mata, G., Kumar, H., and Mahalingam, A. 2018. Performance analysis of a semi-active suspension system using coupled CFD-FEA based non-parametric modeling of low capacity shear mode monotube MR damper. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 0954407018765899.
2. Gurubasavaraju, T. M., Kumar, H., and Mahalingam, A. 2018. An approach for characterizing twin-tube shear-mode magnetorheological damper through coupled FE and CFD analysis. Journal of the Brazilian Society of Mechanical Sciences and Engineering, 40 3, 139.
3. Gurubasavaraju T.M., Hemantha Kumar and Arun M "Evaluation of MR damper force through rheological characterization of magnetorheological fluids" Journal of Engineering Science and Technology - under review.
4. Gurubasavaraju, T. M., Hemantha, K., and Arun, M. 2017. Effect of rheological properties of MR fluid on dynamic performance of semi-active suspension with MR damper. In ICOVP, 13th International Conference on Vibration Problems, Indian Institute of Technology Guwahati, India.
5. Gurubasavaraju T.M, Hemantha Kumar and Arun M 2018, "A study of influence of material properties on magnetic flux density induced in magneto rheological damper through finite element analysis", International Conference on Research in Mechanical Engineering Sciences, MIT Manipal.
6. Keshav M and Sujatha C 2018 Modeling and Optimization of Non-Linear Herschel Bulkley Fluid Model Based Magnetorheological Valve Geometry IEEE ASME International Conference on Advanced Intelligent Mechatronics, Auckland, New Zealand, 9-12 July, 2018.
7. Keshav M and Sujatha C 2018 Comparative Study Of Performance Of Optimized Valve At Different Flow Index Of Rheological Model International Conference on Recent Innovations and Developments in Mechanical Engineering, NIT Meghalaya, Shillong, India, November 8 - 10, 2018.

Patents

1. Patent application No. 201741032388 Patent Title: Active Control for Magnetorheological devices.
2. Patent application No. 201741044515 Patent Title: Road Profile by maps.

Scholars and Project Staff

Research Scholars at NITK
1. Subash Acharya
2. Rangaraj M Desai
3. Aruna M N

Research scholars at IITM
1. Manjeet Keshav Senior Research Fellow - also registered for Ph.D at NITK 1. Abhinandan Hegale 2. Puneet N P Junior reseach fellow - also registered for Ph.D. at NITK 1. Mohibb E Hussain Jamadar 2. Tak Radhe Shyam Saini 3. K. V. Swaroop 4. Ashok Kumar K 5. Pinjala Devikiran

Challenges faced