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Applied Thermo, Lecture-01.pptx

  1. Applied Chemistry Engr. Shakeel Ahmad Introduction, History and Applications
  2. 1. Introduction Thermodynamics is a branch of physics that deals with heat, work, and temperature, and their relation to energy, radiation, and physical properties of matter. The behavior of these quantities is governed by the four laws of thermodynamics which convey a quantitative description using measurable macroscopic physical quantities, but may be explained in terms of microscopic constituents by statistical mechanics. Thermodynamics applies to a wide variety of topics in science and engineering, especially physical chemistry, biochemistry, chemical engineering and mechanical engineering, but also in other complex fields such as meteorology.
  3. 2. Introduction Thermodynamics is a science and, more importantly, an engineering tool used to describe processes that involve changes in temperature, transformation of energy, and the relationships between heat and work. It can be regarded as a generalization of an enormous body of empirical evidence. It is extremely general: there are no hypotheses made concerning the structure and type of matter that we deal with. It is used to describe the performance of propulsion systems, power generation systems, and refrigerators, and to describe fluid flow, combustion, and many other phenomena
  4. 3. Introduction The focus of thermodynamics in aerospace engineering is on the production of work, often in the form of kinetic energy (for example in the exhaust of a jet engine) or shaft power, from different sources of heat. For the most part the heat will be the result of combustion processes, but this is not always the case. The course content can be viewed in terms of a ``propulsion chain'' as shown in Figure, where we see a progression from an energy source to useful propulsive work (thrust power of a jet engine).
  5. History- Before 1800  OTTO VON GUERICKE His major scientific achievements were the establishment of the physics of vacuums, the discovery of an experimental method for clearly demonstrating electrostatic repulsion, and his advocacy of the reality of "action at a distance" and of "absolute space“  R O B E R T B O Y L E Founders of modern chemistry, and one of the pioneers of modern experimental scientific method. He is best known for Boyle's law, which describes the inversely proportional relationship between the absolute pressure and volume of a gas, if the temperature is kept constant within a closed system
  6. History- Before 1800  THOMAS SAVERAY He is famous for his invention of the first commercially used steam powered engine  GUILLAURNE AMANTONS He came close to finding absolute zero. Absolute zero is the lower limit of the thermodynamic temperature scale, a state at which the enthalpy and entropy of a cooled ideal gas reaches its minimum value, taken as 0.  JOSEPH BLACK Introduced term Latent Heat (Latent heat is energy released or absorbed, by a body or a thermodynamic system, during a constant temperature process) and specific heat (The specific heat is the amount of heat per unit mass required to raise the temperature by one degree Celsius)
  7. History,1800-1847  JOHN LESLIE Sir John Leslie observes that, black surface radiates heat more effectively than a polished surface, suggesting the importance of black body radiation.  ROBERT BROWN He introduced a word Brownian Motion. Brownian motion is the random motion of particles suspended in a fluid (a liquid or a gas) resulting from their collision with the quick atoms or molecules in the gas or liquid.  JOSEPH LOSSAC Gay-Lussac first formulated the law, Gay-Lussac's Law, stating that “if the mass and volume of a gas are held constant then gas pressure increases linearly as the temperature rises
  8. History, 1800-1847  EMILE CLAPEYRON Emile Clapeyron popularises Carnot's work through a graphical and analytic formulation. He also combined Boyle's Law, Charles's Law, and Gay-Lussac's Law to produce a Combined Gas Law PV/T = k.  HENRI VICTOR Henri Victor Regnault added Avogadro's Law to the Combined Gas Law to produce the Ideal Gas Law PV = nRT
  9. History, 1847-1948  WILLIUM RANKINE Introduce thermodynamic function, later identified as entropy (a measure of the number of specific ways in which a thermodynamic system may be arranged, commonly understood as a measure of disorder )  RUDOLPH CLAUSIUS Central founders of the science of thermodynamics. By his restatement of Sadi Carnot's principle known as the Carnot cycle, he put the theory of heat  VAN DER WAAL Well known due to van der Waal's equation (this equation is the sum of the attractive or repulsive forces between molecules (or between parts of the same molecule) other than those due to covalent bonds, or the electrostatic interaction of ions with one another, with neutral molecules, or with charged molecules).
  10. History, 1847-1948  HENRY LOUIS He is well known by his principle called as L E CH AT LI E R’ S P RIN CI P L E ( When a system at equilibrium is subjected to change in concentration, temperature, volume, or pressure, then the system re- adjusts itself to (partially) counteract the effect of the applied change and a new equilibrium is established)  WALTER NERNST Relates the voltage of electrochemical cells to their chemical thermodynamics Nernst equation is an equation that relates the reduction potential of a half cell (or the total voltage, i.e. the electromotive force, of the full cell) at any point in time to the standard electrode potential, temperature, activity, and reaction quotient of the underlying reactions and species used  STEPHEN HAWKING One of the most eminent scientist after Einstein. Stephen Hawking predicts that black holes will radiate particles with a blackbody spectrum which can cause black hole evaporation
  11. Applications Heat Engines  One of the most important things we can do with heat is to use it to do work for us. A heat engine does exactly this.  It makes use of the properties of thermodynamics to transform heat into work.
  12. Applications  Heat pumps, air conditioners, and refrigerators utilize heat transfer of energy from low to high temperatures, which is the opposite of what heat engines do.  The purpose of a heat pump is to transfer energy by heat to a warm environment, such as a home in the winter
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