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-   -   High pressure at the end of compression stroke.. (https://www.cfd-online.com/Forums/ansys/164801-high-pressure-end-compression-stroke.html)

Pawan30 January 2, 2016 06:55

High pressure at the end of compression stroke..
 
Hi,
I am simulating the compression stroke of a Diesel Engine in ANSYS ICE workbench.As, the piston move upward in the compression stroke, just before the injection, the pressure calculated by the simulation is more than the actual pressure corresponding to the experimental value.The actual value is about 20bar but, the pressure is calculated about 80bar by the simulation.I am not getting, why the pressure is rising so much in simulation ??
How to solve this problem ??

RHU January 15, 2016 01:49

Have you checked the trapped mass inside the cylinder?

Pawan30 January 15, 2016 10:34

Hi,RHU
How to check the trapped mass inside the cylinder?
I am starting the simulation from IVC.

RHU January 16, 2016 04:27

I havent used Ansys ICE, but try post-processing the mass in cfd-post.
Adjust the initial mass when needed to match the exp. pressure trace. Also check if the compression ratio is correct.

Pawan30 February 17, 2016 15:16

Hey, RHU
I have checked the density of air, trapped inside the cylinder.I have given intial value for temp.(340K) and pressure(1.6 Bar) at IVC. At this point when i checked the density it has a value of 1.63 Kg/m3, which is correct according to the value of temp. and pressure. And, Then I calculated the mass, according to the volume at IVC, but how would I check that, this is correct.
Thanku :), And Sorry for replying late..


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