13.2 Adiabatic and Non-Adiabatic Processes
2 min read•july 25, 2024
Adiabatic processes prevent between a system and its surroundings, unlike non-adiabatic processes. This distinction affects energy changes, with adiabatic systems relying solely on , while non-adiabatic systems involve both heat transfer and work.
Understanding adiabatic principles is crucial for energy balances and system analysis. These concepts help determine and composition changes in various processes, from closed systems to open reactors, and guide problem-solving approaches in thermodynamics.
Adiabatic Processes
Adiabatic vs non-adiabatic processes
Top images from around the web for Adiabatic vs non-adiabatic processes
3.6 Adiabatic Processes for an Ideal Gas – University Physics Volume 2 View original
Is this image relevant?
Adiabatic process - Wikipedia View original
Is this image relevant?
The First Law of Thermodynamics · Physics View original
Is this image relevant?
3.6 Adiabatic Processes for an Ideal Gas – University Physics Volume 2 View original
Is this image relevant?
Adiabatic process - Wikipedia View original
Is this image relevant?
1 of 3
Top images from around the web for Adiabatic vs non-adiabatic processes
3.6 Adiabatic Processes for an Ideal Gas – University Physics Volume 2 View original
Is this image relevant?
Adiabatic process - Wikipedia View original
Is this image relevant?
The First Law of Thermodynamics · Physics View original
Is this image relevant?
3.6 Adiabatic Processes for an Ideal Gas – University Physics Volume 2 View original
Is this image relevant?
Adiabatic process - Wikipedia View original
Is this image relevant?
1 of 3
- Adiabatic processes prevent heat transfer between system and surroundings through thermal insulation (vacuum flask)
- Non-adiabatic processes allow heat exchange with surroundings altering system energy (cooking pot)
- Energy changes in adiabatic systems result solely from work done while non-adiabatic systems involve both heat transfer and work
- Adiabatic processes maintain sealed system boundaries whereas non-adiabatic processes have permeable boundaries for heat flow
- Adiabatic energy exchange occurs through work while non-adiabatic involves both heat and work mechanisms
Applications of adiabatic principles
- governs adiabatic processes:
- For adiabatic systems, , simplifying to
- Non-adiabatic heat transfer calculated using
- Overall energy balance for non-adiabatic:
- Problem-solving approach:
- Identify process type (adiabatic or non-adiabatic)
- Apply relevant equations based on process type
- Calculate temperature changes or heat transfer quantities
Energy Balances and System Analysis
Impact on system energy balance
- Adiabatic conditions conserve energy within system boundaries leading to temperature changes from work or shifts
- Non-adiabatic conditions allow energy exchange with surroundings influencing temperature through heat transfer
- Closed systems maintain constant mass while open systems allow mass transfer (engine cylinder vs continuous reactor)
- Steady-state processes maintain constant properties over time while transient processes involve changing conditions (continuous distillation vs batch reactor startup)
Temperature and composition changes
- Adiabatic temperature change calculated using for constant pressure processes
- Non-adiabatic temperature changes account for heat transfer:
- Chemical reactions in adiabatic processes can alter composition (combustion in sealed container)
- Phase changes in non-adiabatic processes modify system composition (evaporation in open container)
- Final equilibrium state determined by minimizing Gibbs free energy for reacting systems
- Vapor-liquid equilibrium calculations necessary for systems undergoing phase transitions
Key Terms to Review (14)
Closed System: A closed system is defined as a physical system that does not exchange matter with its surroundings but can exchange energy in the form of work or heat. In this context, it is crucial for understanding how processes occur without the addition or removal of mass, while still allowing for energy transformations and interactions. This concept helps in analyzing various chemical processes, as it forms the basis for conservation laws and balance equations that govern energy and material flows.
Energy Balance Equation: The energy balance equation is a fundamental concept used to account for the energy entering, leaving, and accumulating within a system during a specific process. It connects various principles of thermodynamics and conservation laws, allowing for the analysis of energy transformations in processes, whether they are involving physical changes, chemical reactions, or biological systems.
First Law of Thermodynamics: The first law of thermodynamics states that energy cannot be created or destroyed, only transformed from one form to another. This principle is foundational in understanding how energy is conserved and accounted for in various processes, such as chemical reactions and physical changes.
Heat exchangers: Heat exchangers are devices designed to efficiently transfer heat between two or more fluids at different temperatures without mixing them. They are essential in many industrial processes to regulate temperatures, enhance energy efficiency, and recover waste heat. Understanding how heat exchangers operate connects closely with concepts like heat capacity, phase changes, and thermodynamic processes.
Heat transfer: Heat transfer is the process by which thermal energy moves from one body or system to another due to a temperature difference. It plays a critical role in many engineering processes, influencing reaction kinetics, phase changes, and overall system efficiency.
Internal energy: Internal energy is the total energy contained within a system, including kinetic and potential energy of its molecules. This concept is crucial for understanding how energy transfers occur in various processes, as it helps explain changes in temperature and phase. It’s also fundamental in analyzing how energy is conserved and transformed during chemical reactions and physical changes.
Latent Heat: Latent heat is the amount of energy absorbed or released by a substance during a phase change without a change in temperature. This concept is crucial in understanding processes like melting, boiling, and condensation, as it directly impacts heat transfer and energy balances in chemical processes.
Non-adiabatic process: A non-adiabatic process is one in which heat is exchanged between a system and its surroundings, causing a change in the internal energy of the system. This exchange can significantly affect the temperature and phase of the substances involved, making it essential to consider in calculations of energy balances. Non-adiabatic processes contrast with adiabatic processes, where no heat is exchanged, and play a crucial role in understanding real-world chemical processes.
Open System: An open system is a type of system that exchanges both matter and energy with its surroundings. In this context, it plays a crucial role in understanding processes where materials and energy continuously flow in and out, influencing various chemical engineering applications, such as reactions, heat transfers, and mass changes.
Refrigeration cycles: Refrigeration cycles are thermodynamic processes that remove heat from a designated area and transfer it to another location, typically using a working fluid known as a refrigerant. These cycles operate by utilizing the principles of phase changes and latent heat, allowing substances to absorb and release energy during their transitions between liquid and gas states. Additionally, refrigeration cycles can be adiabatic or non-adiabatic, depending on whether they occur without heat exchange with the environment or with some heat exchange taking place.
Specific Heat Capacity: Specific heat capacity is the amount of heat required to raise the temperature of a unit mass of a substance by one degree Celsius (or one Kelvin). This concept is crucial in understanding how materials respond to heat, and it connects closely to other important thermodynamic properties and processes.
Temperature: Temperature is a measure of the average kinetic energy of the particles in a substance, indicating how hot or cold that substance is. It plays a critical role in various physical and chemical processes, influencing reaction rates, phase changes, and energy transfers. Understanding temperature helps in analyzing system behavior, energy balances, and thermodynamic processes.
Thermal energy: Thermal energy is the internal energy present in a system due to the random motion of its particles, which relates to temperature and heat transfer. This form of energy is crucial in understanding how energy is conserved and transformed during chemical processes. It plays a significant role in various phenomena, such as phase changes and reactions, influencing the system's behavior under different conditions.
Work Done: Work done refers to the energy transferred when a force is applied to an object over a distance. It plays a crucial role in understanding energy transformations during physical and chemical processes, connecting the movement of matter with energy changes in both adiabatic and non-adiabatic conditions, as well as in the context of coupled material and energy equations.