Kulkarnis researches were mainly in the fields of Chemical Reaction Engineering, Applied Mathematics and Transport phenomena and he is known for his work on fluidized bed reactors and chemical reactors. He is credited with introducing an integer-solution approach and novel ideas on noise-induced transitions and his work on Artificial Intelligence-based evolutionary formalisms is reported to have assisted in a better understanding of reacting and reactor systems. His work spanned from conventional chemical reaction engineering in gas-liquid and gas-solid catalytic reactions to reactor stability to stochastic analysis of chemically reacting systems as well as inter-disciplinary fields. A model reaction system termed Encillator, an analytical approach for the solving model equations based on arithmetics, use of initial value formalism for modelling fluidized-bed reactors, introduction of normal form theory, evolutionary algorithms and stochastic approximation in analysing reactor behavior and performance are some of the contributions made by him. He holds US and Indian patents for several processes he has developed which include Method and an Apparatus for the Identification and/or Separation of Complex Composite Signals into its Deterministic and Noisy Components, Process for preparation of pure alkyl esters from alkali metal salt of carboxylic acid, and Enantioselective resolution process for arylpropionic acid drugs from the racemic mixture'.
Kulakrnis researches have been documented in several peer-reviewed articles; and the online article repository of Indian Academy of Sciences has listed 250 of them. Besides, he has contributed chapters to books edited by others and has published seven edited or authored texts, including Recent Trends in Chemical Reaction Engineering, Advances in Transport Processes, The Analysis of Chemically Reacting Systems: A Stochastic Approach and Transport processes in fluidized bed reactors. He has guided several masters and doctoral scholars in their studies and has conducted training for students on mathematical modelling. He also serves as one of the directors of Hitech Bio Sciences India Limited, a probiotics and nutraceuticals manufacturer based in Pune and is a member of the advisory committee of the International Conference on Sustainable Development for Energy and Environment (ICSDEE 2017).