Equation of mass flow rate through inlet in turbojet engines

This is a very specialized area. What do you mean by 'equation of mass flow rate through inlet in turbojet engines'? Steady state behaviour can be very different from transient behaviour. There is a 200+ page book from NASA that is available for study which describes DYNGEN - A program for calculating the Steady State and Transient performance of Turbojets and Tubofans.
The differential equations associated with the design are difficult to solve . The program describes an Euler approximation procedure for solving these. If you are interested you can download the book (it is unclassified and cleared for unlimited distribution) here:
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