## What is Reynolds transport theorem in fluid mechanics?

Reynolds transport theorem states that the rate of change of an extensive property N, for the system is equal to the time rate of change of N within the control volume and the net rate of flux of the property N through the control surface.

**Is Reynolds transport theorem Lagrangian?**

The time derivative of an integral over a moving fluid volume (a Lagrangian quantity) can be transformed into the equivalent Eulerian conservation law for the corresponding intensive quantity, i.e., mass density or momentum density, by means of the Reynolds Transport Theorem (Section 3.3).

**What is the relationship between material derivative and Reynolds Transport Theorem?**

What is the relationship between the Reynolds transport theorem and the material derivative? A. The Reynolds transport theorem is the integral equivalent of the material derivative.

### What is the relationship between the Reynolds transport theorem and the material derivative?

19. What is the relationship between the Reynolds transport theorem and the material derivative? A. The Reynolds transport theorem is the integral equivalent of the material derivative.

**Does Reynolds transport theorem apply to unsteady flow?**

(a) The Reynolds transport theorem is useful for transforming conservation equations from their naturally occurring control volume forms to their system forms. (c) The Reynolds transport theorem can be applied to both steady and unsteady flow fields.

**What is the physical principle behind momentum equation?**

1. What is the physical principle behind momentum equation? Explanation: Momentum equation is derived using Newton’s second law of motion. This gives a relationship between force and acceleration.

#### What is material derivative in fluid mechanics?

The material derivative computes the time rate of change of any quantity such as temperature or velocity (which gives acceleration) for a portion of a material moving with a velocity, v . If the material is a fluid, then the movement is simply the flow field.

**What is the difference between material derivative and derivative with respect to time in fluid flow?**

For example, in fluid dynamics, the velocity field is the flow velocity, and the quantity of interest might be the temperature of the fluid. In which case, the material derivative then describes the temperature change of a certain fluid parcel with time, as it flows along its pathline (trajectory).

**What is a Streakline in fluid mechanics?**

A streakline is a curved line formed by a string of fluid particles which have passed through a certain point. An example of a streakline is the trail of smoke from a chimney. For a flow which does not change with time, the streamline, streakline, and pathline are the same line.