Abstract

This study aimed at the modelling of a tubular thermal cracker in two and three dimensions using 0.15 kg/h of ethane and 1.5 kg/h of nitrogen in laminar flow using a molecular mechanistic model for ethane cracking, followed by the solution and comparison of the results obtained. This was used to find the effect that spatial development had on the generated profiles. The purpose was achieved by deriving the requisite model equations from mass, energy and momentum balances consisting of nine coupled partial differential equations for each of the spatial considerations and using the finite difference numerical scheme to solve. Throughout the reactor length of 1.20 m and radius of 0.0125 m, the resulting concentration and temperature profiles were predicted. In comparison, the profiles from the two and three dimensional developments showed that even though angular variations are small in the three dimensional approach, they are still present and there consideration could be helpful in the design of tubular thermal crackers.

Keywords:

Finite difference, modelling, partial differential equations, Three Dimensional (3-D), tubular thermal cracker, Two Dimensional (2-D),

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