work, heat pump and energy transformation

How Heat Transfer and Energy Transformation be Used to Do Work

1. How Heat Transfer and Energy Transformation be Used to Do Work

2. HEAT Heat flows from a hotter object to a cooler object when the two objects are placed in contact. It is a normal process. Thermal energy transferred between two systems at different temperatures that come in contact.

3. HEAT PUMP a device that allows heat to transfer from a cold reservoir to a warmer one heat flows from lower temperature to higher temperature, it needs mechanical energy to happen

4. SPONTANEOUS on its own, natural Heat flows normally from higher temperature to lower temperature NON-SPONTANEOUS does not take place on its own Happens when heat flows from lower temperature to higher temperature.

5. Work is required for the heat to flow from a lower to a higher temperature.

6. The First Law of Thermodynamics It states that heat energy cannot be created or destroyed. It can, however, be transferred from one location to another and converted to and from other forms of energy.

7. The Second Law of Thermodynamics It states that heat will never of itself flow from a cold temperature to a hot temperature object.

8. REFRIGERATION CYCLE .

9. REFRIGERATION CYCLE . Four main processes: Compression Condensation Expansion Evaporation

10. REFRIGERATION CYCLE . The refrigeration cycle starts and ends with the compressor . The refrigerant flows into the compressor where it is compressed and pressurized . At this point, the refrigerant is a hot gas .

11. REFRIGERATION CYCLE . The refrigerant is then pushed to the c ondenser which turns the vapour into liquid and absorbs some of the heat. The refrigerant then proceeds to the expansion valve where it expands, losing pressure and heat.

12. REFRIGERATION CYCLE . The refrigerant coming out of the expansion valve is cold and slow due to the loss of pressure. It enters the evaporator in a liquid state where the exchange of heat takes place thus cooling the load inside the refrigerator.

13. REFRIGERATION CYCLE . As the gas cools down the load, it absorbs the heat which turns it into a gas. The gas is then pushed back into the compressor where it can start the cycle again.

14. . • Spoilage of food • Melting of ice • Waterfall • Breakage of egg • Rice cooking • Drying of leaves Spontaneous Process (SP) or Non-Spontaneous Process (NSP)