Explain geometric similanty and dynamic similarity

An engineering model is said to have similitude with the real application if the two share a geometric, kinematic and dynamic similarity. The principle of similarity underlies the entire subject of dimensional analysis.

Geometric similarity: when two geometrical objects have the same shape or mirror one another, they are called similar. If the model has geometric similarity it means it is the same shape as the application, usually scaled. Dynamic similarity: this similarity happens when ratios of all forces acting on corresponding fluid particles and boundary surfaces in the two systems are constant., The relative importance of different types of forces (for example viscous and inertial forces) must be the same for the model and prototype.

I hope you find this information useful and interesting! Good luck!