Applicability of the Omega method

An improved nozzle correlation close to the thermodynamic critical temperature is given by Leung in reference 4. 

The above conditions of applicability apply even when the Omega parameter is evaluated by the most accurate method, i.e. using equation (A8.4) and making use of computerised physical property calculations. Alternatively, simplified equations for evaluating Omega can also be used (equations (A8.5) to (A8.10)). These introduce a further condition of applicability  

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