Category Archives: Engineering Thermodynamics

Stirling Cycle | Efficiency, P-V & T-S Diagrams | Heat & Work Table

By | May 3, 2019

Stirling cycle is a thermodynamic cycle upon which a Stirling Engine works. Stirling engine is a closed cycle regenerative heat engine. It works on either air or any other gas. Stirling cycle is invented by Robert Stirling with help from his brother (in 1816). Below are P-V and T-S Diagrams of the Stirling Cycle. Stirling… Read More: Stirling Cycle | Efficiency, P-V & T-S Diagrams | Heat… »

Joule Thomson Effect | Joule Thomson Coefficient

By | March 18, 2019

Joule Thomson effect Before moving to the topic we should first know that Joule Thomson effect, Joule Thompson effect, Joule kelvin effect, Joule Thomson expansion, Joule kelvin expansion are the different names of the same thing. To understand the Joule Thomson effect, it is very important to first understand Throttling process. Throttling process: Throttling is… Read More: Joule Thomson Effect | Joule Thomson Coefficient »

Second Law Efficiency [Turbine and Compressor]

By | March 16, 2019

Second law efficiency We all know the general formula for calculating efficiency of a heat engine. It is a ratio of output work to input heat. This formula for calculating efficiency is in line with first law of thermodynamics. Which deals with the conservation of quantity of energy (not quality). But when it comes to… Read More: Second Law Efficiency [Turbine and Compressor] »

Exergy or Availability in Thermodynamics | Dead State in Thermodynamics

By | March 14, 2019

When a system is not in equilibrium (or dead state in this case) with its surroundings there is an opportunity in convert this departure from equilibrium to do some useful work. For example; If there is a difference between the temperature of system and surroundings then this temperature difference can be utilized to produce useful… Read More: Exergy or Availability in Thermodynamics | Dead State in Thermodynamics »

Clausius’ Inequality and Clausius’ Theorem

By | March 10, 2019

Clausius’ theorem The cyclic integral of ∂Q/T for a reversible cycle is always equal to zero. Proof of Clausius’ theorem: Let’s consider a reversible heat engine. From the absolute thermodynamic scale of temperature, we know that for a reversible process Q1/Q2 = T1/T2 Q1/T1 – Q2/T2 = 0 Q1/T1 + (-Q2)/T2 = 0 ΣCYCLE (Q/T)… Read More: Clausius’ Inequality and Clausius’ Theorem »

Entropy: How it’s Originated in Thermodynamics [Fully Explained]

By | March 10, 2019

Birth of Entropy Entropy is the degree of randomness of a thermodynamic system. In this article we will discuss how the concept of Entropy is originated in thermodynamics. Let’s consider a reversible heat engine. From the absolute thermodynamic scale of temperature, we know that. Q1/Q2 = T1/T2 Q1/T1 – Q2/T2 = 0 Q1/T1 + (-Q2)/T2… Read More: Entropy: How it’s Originated in Thermodynamics [Fully Explained] »

Carnot Cycle | Carnot Heat Engine | Efficiency, P-V & T-S Diagrams

By | May 4, 2019

Carnot Cycle Carnot Heat engine (based on Carnot Cycle) was a concept developed by Nicolas Leonard Sadi Carnot (1796-1832, a French Military Engineer and Physicist) so that one can visualize a reversible heat engine in practice. Carnot engine is a reversible heat engine which works on Carnot cycle. Carnot cycle comprises of four processes. Reversible… Read More: Carnot Cycle | Carnot Heat Engine | Efficiency, P-V &… »

Absolute Thermodynamic Scale of Temperature

By | March 1, 2019

Absolute thermodynamic scale of temperature Here in this article we are going to define absolute thermodynamic scale of temperature with the help of a reversible heat engine. From the Carnot’s theorem we know that all the reversible heat engines operating between the same temperature limits have the same efficiency. Which means that efficiency of a… Read More: Absolute Thermodynamic Scale of Temperature »

Carnot’s Theorem and its Proof [with Diagrams]

By | March 3, 2019

Carnot theorem No heat engine can be more efficient than a reversible engine operating between the same temperature limits (the temperature of heat addition and the temperature of heat rejection) and all reversible heat engines operating between the same temperature limits have the same efficiency. Proof of Carnot theorem Given: t1: Temperature of the source… Read More: Carnot’s Theorem and its Proof [with Diagrams] »