18
JUN
2015

G. Venkatarathnam, Ph.D.,

Institute Chair Professorgvenkat.jpg

Office Room No : 205, Refrigeration and Air Conditioning Laboratory
Tel: (O) : +91 44 2257 4685
Email :
Personal webpage:


Research interests

  • Development of Low GWP Refrigerant mixtures
  • Improvement of efficiency of Refrigeration and Air conditioning Systems
  • New refrigeration and liquefaction processes operating with mixtures
  • Heat exchangers – Modelling, additive manufacturing, testing
  • Thermodynamics of mixtures

Courses taught

  • ME1100 Thermodynamics (Undergraduate)
  • ME3250 Refrigeration and Air Conditioning (Undergraduate)
  • ME4100 Design Project (Undergraduate)
  • ME6003 Refrigeration and Cryogenics (Graduate)
  • ME5134  Process Simulation (Graduate)

Patents Granted

  • Venkatarathnam, G., Refrigerant composition and process for preparation thereof, US Patent No. 7722780 (2010)
  • Venkatarathnam, G., Refrigerant composition for refrigeration systems, US Patent No. 7582223 (2010)
  • Venkatarathnam, G., A refrigerant composition for refrigeration systems, India Patent No. 211627 (2007)
  • Venkatarathnam, G., A refrigerant composition for a single stage refrigeration system, India Patent No. 205644 (2007)
  • Venkatarathnam, G., A refrigerant composition for refrigeration systems, India Patent No. 197997 (2006)

Patents Applications Pending

Three Indian, and One PCT application


Technologies developed and available for commercialisation

  1. Battery coolers
  2. Perforated plate matrix heat exchangers
  3. Biofreezers
  4. Mixed refrigerant cycle refrigerator operating between -40 °C and -100 °C
  5. Mixed refrigerant cycle refrigerator operating between 70 and 150 K
  6. Mixed refrigerant cycle nitrogen liquefier with a liquefaction rate of 0.7-0.9 l/hr and a power input of about 1.5 kW

Thermodynamic Methods and Routines

Our phase identification parameter is actively used in the fitting of Helmholtz energy equations of state of a number of fluids at NIST and elsewhere. Similarly, our Density marching methods for phase envelope calculations are used in a number of process simulation and thermodynamic programs. Here are some of the well known software that use our methods and routines:

  • NIST Refprop property program – Phase identification method, phase envelope routine, true mixture critical point routine
  • Aspen Plus Process simulation software – Two and Three Phase envelope calculation methods
  • Aspen Hysys Process simulation software – Phase identification method
  • Coolprop property program – Phase identification method, Phase envelope calculation method

Software developed by us

  • MYPROPS – Program for the estimation of thermodynamic properties of mixtures  (VLE, VLLE, VLSE), routines for drawing phase envelopes based on the density marching method for phase envelope (parts I, II, III), etc.
  • MYCOIL – Program for the simulation of different types of heat exchangers
  • MRC-OPTIM – Program for the optimisation of J-T refrigerators operating with mixtures
  • MHE-OPTIM – Program for the optimum design of perforated plate matrix heat exchangers
  • COILHX – Program for the design and simulation of wound coil heat exchangers
  • CRYOSIM – General purpose process simulation program

 


Selected Publications

Books & Handbook Chapters

  1. G. Venkatarathnam, Cryogenic Mixed Refrigerant Processes, Springer, NY, 2008
  2. G. Venkatarathnam, Cryogenic Heat Exchangers, Heat Exchanger Design Handbook, Begell House, 2016

 

Journals & Conferences

  1. H. Kruthiventi and G. Venkatarathnam, Performance of J-T refrigerators operating with mixtures and coiled
    wire finned heat exchangers, Journal of Thermal Analysis and Calorimetry (Accepted) (2020)
  2. Vineed Narayanan and G. Venkatarathnam, Prediction of vapour-liquid equilibria of binary mixtures of neon-nitrogen, neon-oxygen and neon-argon used in J-T refrigerators, Cryogenics (Accepted) (2020)
  3. Sunil Jerome and G. Venkatarathnam, Performance of a Linde-Hampson refrigerator operating from –120 °C to –60 °C with optimised R14-hydrocarbon mixtures exhibiting vapour-liquid-liquid equilibria, Heat Mass Transfer,  doi:10.1007/s00231-019-02801-z (2019)
  4. T. Barath Adithya and G. Venkatarathnam, A review of second-order isobaric-isothermal flash calculations, paper no. NCCS_TP_1029, National  conference on Cryogenics for Space, Thiruvanathapuram, 12-14, December 2019
  5. V. Chaitanya, S. Narasimhan and G. Venkatarathnam, Effect of assumption of common stream temperature in the simulation of multistream heat exchangers on the overall process efficiency, paper no. NCCS_TP_1015, National  conference on Cryogenics for Space, Thiruvanathapuram, 12-14, December 2019
  6. G. Venkatarathnam, Some exciting developments in cryogenic engineering applications, Invited paper, National  conference on Cryogenics for Space, Thiruvanathapuram, 12-14, December 2019
  7. G. Venkatarathnam, Alternatives for low GWP refrigerants for India, Invited paper, International conference on Recent advancements in Air conditioning and Refrigeration, RAAR-2019, Bhubaneswar, 28-30, November 2019
  8. G. Venkatarathnam, Performance of A Small Nitrogen Liquefier, 27th “National Symposium on Cryogenics and Superconductivity, Mumbai, January 16-18, 2019
  9. G. Venkatarathnam, Three-phase routines for the NIST Refprop program, 27th “National Symposium on Cryogenics and Superconductivity, Mumbai, January 16-18, 2019
  10. H. Gurudath Nayak and  G. Venkatarathnam, Performance of an auto refrigerant cascade refrigerator operating in gas refrigerant supply mode with optimized nitrogen- hydrocarbon refrigerant mixtures, Paper No. PA-C-001,the sixth International Conference on Cryogenics and Refrigeration, April 12–14, 2018 at Shanghai Jiao Tong University, Shanghai, China
  11. R. Satya Maher and G. Venkatarathnam, Estimation of performance of a J-T Refrigerators Operating With Nitrogen-Hydrocarbon Mixtures and a Coiled tubes-in-tube heat exchanger, Cryogenics, 92, 27-35 (2018)
  12. I.Sujatha and G. Venkatarathnam, Comparison of performance of a vapor absorption refrigeration system operating with some hydrofluorocarbons and hydrofluoroolefins as refrigerants along with ionic liquid [hmim][TF2N] as the absorbent, Int. J. Refrigeration, 88,370-382 (2018)
  13. V. Narayanan and G. Venkatarathnam, Prediction of Vapour-Liquid and Vapour-Liquid-Liquid equilibria of nitrogen-hydrocarbon mixtures used in J-T refrigerators, Cryogenics, 90, 70-85 (2018)
  14. G. Venkatarathnam, density marching method for drawing phase envelopes: 3. P-xy diagrams of binary mixtures, Ind. Eng. Chem. Res., 56 (46),  13894–13904  (2017)
  15. I. Sujatha and G. Venkatarathnam, Performance of a vapor absorption heat transformer operating with ionic liquids and ammonia, Energy, 141, 924-936  (2017)
  16. S.S. Harish Kruthiventia and G. Venkatarathnam, Studies on capillary tube expansion device used in J-T refrigerators operating with nitrogen-hydrocarbon mixtures, Cryogenics, 87, October 2017, 76-84 (2017)
  17. H. Gurudath Nayak and G. Venkatarathnam, Occurrence of Dry out Phenomenon in an Auto Refrigerant Cascade Refrigerator operating with zeotropic mixtures, ASME J. Thermal Sci. Eng., 9(3):031012-031012-6. doi:10.1115/1.4035940 (2017).
  18. B. Sreenivas, H. Gurudath Nayak and G. Venkatarathnam, Relationship between composition of mixture charged and that in circulation in an auto refrigerant cascade and a J-T refrigerator operating in liquid refrigerant supply mode, Cryogenics 81, 42-46, (2017)
  19. Padmanabhan, C.S. Gurudath, Thota Srikanth, A Ambirajan, S.A. Basavaraj, Kumar Dinesh, and G. Venkatarathnam,  Studies on Phase Shifting Mechanism in PulseTube Cryocooler, IOP Conf. Ser.: Mater. Sci. Eng. 171 012082 (2017)
  20. Vineed Narayanan, G VenkatarathnamExperimental investigation on mixed refrigerant cryocooler operating at 70 K for cooling high temperature superconductors, IOP Conference Series: Materials Science and Engineering 171 (1), 012073 (2017)
  21. V. Narayanan and G. Venkatarathnam, Performance of two mixed refrigerant processes providing refrigeration at 70K, Cryogenics, 78, 66-73 (2016)
  22. P.C. Jayanti, and G. Venkatarathnam, Identification of the phase of a substance from the derivatives of pressure, volume and temperature, without prior knowledge of saturation properties: Extension to solid phase, Fluid Phase Equilibria, 425, 269-277 (2016)
  23. G. Sharma, R.L. Gardas, A. Coronas and G. Venkatarathnam, Effect of anion chain length on physicochemical properties of N, N-dimethylethanolammonium based protic ionic liquids, Fluid Phase Equilibria, 415, 1-7 (2016)
  24. Harish Kruthiventi SS, Venkatarathnam GG. Comparison of the Straight Adiabatic Capillary Tube Expansion Devices Used in Refrigeration Systems Operating With Refrigerants R134a and R1234yf. ASME. J. Thermal Sci. Eng. Appl., 8, 021015-1–021015-7 (2016)
  25. G. Venkatarathnam, Thermodynamics of refrigerant mixtures used in J-T refrigerators, Presented at the 26th International Cryogenic Engineering Conference, March 7-11, 2016, New Delhi
  26. G.S.C. Prasad, C.S. Kumar, S.S. Murthy and G. Venkatarathnam, Performance of an organic Rankine cycle with multicomponent mixtures,Energy, 88, 690-696 (2015)
  27. B. Sreenivas, D.R. Patel, S.S. Murthy, and G. Venkatarathnam, Performance of mixed refrigerant cascade refrigerator for cooling a space simulation chamber, Indian Journal of Cryogenics 39 (1), 81-85 (2014)
  28. G. Venkatarathnam, Density Marching Method for Calculating Phase Envelopes, Ind. Eng. Chem. Res. 53, 3723−3730 (2014)
  29. G. Venkatarathnam, Density marching method for calculating phase envelopes: Part II – Three-phase envelopes, Ind. Eng. Chem. Res. Vol. 53, 12122-12128 (2014)
  30. Sumit K. Swarnkar, S. Srinivasa Murthy, Ramesh Gardas and G. Venkatarathnam, Performance of a vapour absorption refrigeration system operating with ionic liquid-ammonia combination with water as cosolvent, Applied Thermal Eng. Vol. 72, 249-256 (2014)
  31. G. Venkatarathnam, Thermodynamics of refrigerant mixtures used in Cryogenic Mixed Refrigerant Processes, National Symposium on Cryogenics, Hyderabad, December 8-10, 2014, Hyderabad, India
  32. Sunil Jerome and G. Venkatarathnam, Comparatative study of Helmholtz, Peng-Robinson and PC-SAFT equation of state applied to a J-T Cryocooler, National Symposium on Cryogenics, Hyderabad, December 8-10, 2014, Hyderabad, India
  33. Vineed Narayanan and G. Venkatarathnam, A mixed refirgerant cycle for providing refrigeration below 70 K for superconducting application, National Symposium on Cryogenics, Hyderabad, December 8-10, 2014, Hyderabad, India

Some important projects undertaken for industrial clients

  1. Development of new refrigerants for room temperature applications
  2. Improvement of COP of an air conditioner
  3. Improvement of performance of a -80 °C biofreezer
  4. Studies on low temperature container refrigeration system
  5. Diagnosis and detection of faults in large chillers
  6. Design of multistream Wound Coil heat exchangers
  7. Cooling of high Tc superconducting transformer
  8. Cooling of low Tc superconducting generator
  9. Studies on chill down of large pipelines
  10. Studies on stratification of cryogens in large tanks under different conditions
  11. Studies on chill down of turbopumps
  12. Very high effectiveness heat exchangers for a helium liquefier

In Press

  1. The Hindu article on low temperature refrigerator
  2. Times of India article on nitrogen liquefier

Also taught at

  • Indian Institute of Technology Kharagpur
  • University of Karlsruhe, Germany (now known as Karlsruhe Institute of Technology)