Introduction To The Final Year Mechanical Project:

              The potential of cryogenic energy storage for automotive propulsion serves as an alternative for the usage of electrochemical batteries. This project “Quasi isothermal expansion for cryogenic automotive propulsion” is used in zero emission vehicles. It’s also assumed that using inert cryogen like liquid nitrogen as an energy storage material would limit the environmental damage.


            In this project Quasi isothermal expansion for cryogenic automotive propulsion, the cryogenic fuel is stored in a vacuum jacketed container and has proper relief valves to accommodate safe boil off. A cryo-pump is employed to pressurize the fluid to a level above the injection pressure of expander. The shaft power from this expander is applied for vehicle propulsion.

      To maintain the expander walls at ambient temperature, a warmant fluid is circulated. This warmant must be pumped through the heat exchanger system for efficient conduction of ambient heat into engine. A quasi isothermal reciprocating expander is designed and the output is transmitted to the wheels by transmission.


       The potential for making use of the available energy of liquid nitrogen for the purpose of automotive propulsion is very high. The heat transfer calculation of this quasi isothermal engine has a heart core which is embedded within the expansion chamber and nearly 85% of performance of ideal isothermal power cycle is obtained. Since this cryogenic fluid is non-polluting, it avoids heavy metal pollution linked with lead-acid batteries.

             Furthermore, in this project the complete thermodynamic simulation of a reciprocating expander is studied. It has been developed to study the various engine designs and operational parameters of liquid Nitrogen consumption of this ambient powered automobile. Thus in steps, a reciprocating engine model along with piston cylinder heat transfer and piston ring friction mechanism is explained in detail.

Download Quasi-Isothermal Expansion Engine for Cryogenic Automotive Propulsion Mechanical Project Report.