adiabatic vs isothermal process

Upload: shahrin-febrian

Post on 02-Jun-2018

224 views

Category:

Documents


0 download

TRANSCRIPT

  • 8/11/2019 Adiabatic vs Isothermal Process

    1/2

    Q: Explain the Difference between adiabatic and isothermal compression?

    A: An adiabatic compressor does not exchange heat with its surroundings so the temperature of the compressed material will increase, in an isothermal compressorthe material's temperature is kept constant by expelling heat to it's surroundings.

    Q: Difference between isothermal and adiabatic process?

    A: Isothermal process is going on under constant temperature, adiabatic is a process where no heat is exchanged (this does not imply that temperature is constant).

    ---------------------------------------------Adiabatic process: no heat is transferred.Isothermal process: occurs at a constant temperature.

    It might appear that temperature cannot change if no heat is added, but that isnot the case. You can increase the temperature of a gas by compressing it; evenif the piston and cylinder are insulated against heat transfer. Essentially, thecompression process takes mechanical work and converts it to both an increase in pressure and an increase in temperature.

    You can increase the temperature of a gas in an adiabatic process if you do some

    mechanical work on the gas.

    ---------------------------------------------If I was able to decrypt your question correctly, you are asking about the difference between isothermal and adiabatic processes.

    This comes down to the difference between temperature and heat. If you can understand that much, you are understanding the difference between isothermal and adiabatic processes. Temperature is measured with a thermometer. Heat is measured in energy units, such as calories.

    By the same token, if you totally insulate a system from heat gain or loss, thetemperature inside may change due to heat of reaction, pressure changes, volume

    changes, et cetera. This is an adiabatic system. Now take the same system and apply heat or cooling (actually, it is more accurate to say that you are removingheat than 'cooling') to keep the temperature constant, that is an isothermal system.

    So, adiabatic=same energy, isothermal=same temperature

    -----------------------Adiabatic Vs Isothermal

    In the realm of Physics, specifically in the subject thermodynamics, there are two often discussed concepts that are frequently used in industrial practical application. These concepts are the adiabatic and isothermal processes.

    These two processes are the opposite sides of the coin. They are the poles located at opposite ends so to speak. Firstly, otherwise known as an isocaloric process, the adiabatic process is when theres no transfer of heat from or towards thefluid being worked on. Besides, adiabatic would mean impassable if defined literally. Thus, heat is not able to penetrate.

    When theres an actual gain or heat loss in the surroundings then the process is termed adiabatic. Because the temperature can change in an adiabatic process dueto internal system variations, the gas in the system may tend to cool down when

  • 8/11/2019 Adiabatic vs Isothermal Process

    2/2

    expanding. In this connection, it would also mean that its pressure is significantly lesser compared to the other process (isothermal) at a given volume.

    As mentioned, the process at the other extreme end that permits transfer of heatto the surroundings, and thus, making the overall temperature constant (do notchange) is called an isothermal process. If you come to think of it, the word isothermal when interpreted literally would mean iso(the same), thermal(temperature. Hence, there is the same temperature.

    In a thermodynamic system, the two main processes involved are adiabatic or isothermal. It is regarded as the former when the transformation (fluctuations or variations in temperature) are fast enough that no heat was significantly transferred between the outside environment and the system. When the transformation is very slow in that same system then the process is isothermal because the temperature of the system remains the same through the exchange of heat with the outer environment.

    1. In an isothermal process, there is an exchange of heat between the system andthe outside environment unlike in adiabatic processes wherein there is none.

    2. In an isothermal process, the temperature of the material involved remains the same unlike in adiabatic processes wherein the temperature of the material being compressed may raise.

    3. In an isothermal process, heat can be added or released from the system justto keep the same temperature while in an adiabatic process, theres no heat addedor released because maintaining constant temperature will not matter.

    4. In an isothermal process, the transformation is slow while in an adiabatic process it is fast.