Tocol Machine Tools Pvt Ltd

DrAmine, Thank you for your prompt response. 
The reference pressure is 0 atm (mentioned above)
1. If the pressure values are gauge pressures, how can it be in orders of -440 KPa. 
2. Could you please elaborate on your second point.
3. Yes i agree to your point, but how can one show negative total pressures? Is there a better way to justify negative pressures?
4. Would you like to see any additional contours/plots?