Tiêu đề 1.1 Introduction to fluid mechanics.pdf ✅

Unit 1

Fluid • Fluid: A substance in the liquid or gas phase. • A solid can resist an applied shear stress by deforming. • A fluid deforms continuously under the influence of a shear stress, no matter how small. • In solids, stress is proportional to strain, but in fluids, stress is proportional to strain rate. • When a constant shear force is applied, a solid eventually stops deforming at some fixed strain angle, whereas a fluid never stops deforming and approaches a constant rate of strain.