thanks for your reply but can u please answer my questions ?is there a problem for minimizing face quality limit value to 0.2 ? how to check if it distort surface mesh ?ni think quality improvement collapse skewness limit should be more than 0.7 or more ? so that we can avoid bad skewness faces ? , i think it acts like upper limit value for skewness so no cell will have skewness more than that valuendoes collapsing mesh change geometry ? thats the tradeoff i thinkn