Clausius Inequality, Entropy and Irreversibility – Introduction

What is Clausius Inequality?

There are 2 laws that are associated with Clausius Inequality concept. The first law states the process of internal energy, while in case of the second law the major concern is process of entropy. In both these laws, there are mathematical formulations that have been done, and now the matter of primary concern is entropy.

Amidst the processes that are acceptable and has a role to play in this branch of thermodynamics, it is the reversible process that is of primary concern. So, to determine this concept, it is important that this reversible aspect is taken into consideration and Claudius Inequality is the core of this process.

It implies second law of thermodynamics to be stated in a mathematical manner wherein relation between heat flow, entropy and surroundings of a specific system is to be taken into account.

Another notable point is Carnot efficiency that provides maximum amount of efficiency in this regard. Keeping heat level at maximum efficiency point, heat transfer should take place both at the highest and lowest reservoir points. In this manner, heat is absorbed from the sources of temperature and further released to temperature sink, via the sub process. Heat engine has an important part to play in that further releasing process.

What is Ir reversibility?

This is important for increasing entropy of universe. In thermodynamics, if there is a change in the system and its surroundings, there is no chance of reverting back to the old process even by sudden minor changes. Though certain systems are capable of returning back to their original system, yet initial conditions have to be brought back. With this irreversible process entropy within the universe can increase to a great level.

What is entropy?

In this case, there is a specific thermodynamic quantity which represents a system where thermal energy is not available for converting into mechanical work, and there is a sudden sense of randomness in the whole process.

So, all the exact state of the molecules can be found in this process.

Links of Previous Main Topic:-

• Introduction to statics
• Introduction to vector algebra
• Two dimensional force systems
• Introduction concept of equilibrium of rigid body
• Friction introduction
• Introduction about distributed forces
• Area moments of inertia in rectangular and polar coordinates
• Mass moment of inertia introduction
• Work done by force
• Kinematics of particles
• Position vector velocity and acceleration
• Plane kinematics of rigid bodies introduction
• Combined motion of translation and rotation
• Rectilinear motion in kinetics of particles
• Work and energy
• Linear momentum
• Force mass acceleration
• Simple stress introduction
• Normal strain
• Statically indeterminate system
• Introduction to thermodynamics
• Statement of zeroth law of thermodynamics with explanation
• Heat and work introduction
• First law of thermodynamics for a control mass closed system undergoing a cycle
• Open system and control volume
• Conversion of work into heat
• Introduction to carnot cycle

Links of Next Mechanical Engineering Topics:-

• Reversible adiabatic paths do not intersect
• Clausius theorem
• Entropy
• Entropy temperature plot
• Clausiuss inequality
• Entropy change in an irreversible process
• Principle of increase of entropy
• The degree of irreversibility of and irreversible process
• Summary of first and second law by clausius  
• Practical use of entropy principle
• First law and second law combined
• Analysis of thermodynamic equations