The depth of cut in machining depends on work piece material, rigidity of the machine set up, cutting tool geometry, etc. For common soft steel, I would suggest start at 1mm of depth of cut in turning to validate model.

dear Gokul Krishna, your problem is a principle problem which results from simplifying a 3D process (model) to an 2D model. The material volume that you machine depends on the uncut cross-sectional area (feed x ap or h x b) which is oriented perpendicular to the cutting direction (vc). Since you do not have the 3.dimension in 2D (e.g. the width), all your units are scaled by unit length. In 2D you also do not have the specific cutting edge geometry and orientation, unless you do orthogonal cutting. So you need to think hard, what you intend to model and what you are modeling.

Typical turning situation is not exactly orthogonal as the chip does not flow along the orthogonal plane. The chip deviates from the orthogonal plane due to restricted cutting effect (participation of the tooltip and the auxiliary cutting edge in the cutting process), the finite nose radius (say 0.8 mm) and non-zero inclination angle.

But you have carried out a 2D simulation of cutting process assuming it to be orthogonal and now you would like to validate it by experimental trials.

Try to carry out experiments with cutting tools with a small nose radius (0.4 mm instead of 0.8 or 1.2 mm - I am assuming that you would be using uncoated/coated tungsten carbide inserts) and your ratio of the depth of cut to feed should be as large as possible - say the depth of cut of 2 mm and feed of 0.1 mm. That would provide you a large ratio of 20 and very little deviation of the chip from the orthogonal plane (and almost achieving orthogonal machining while carrying out the experiments)