JET Interview Questions and Answers

The T-s, p-v, h-s diagrams are graphical representations of thermodynamic cycles used in vapor, gas, and refrigeration systems.

• T-s diagram shows the relationship between temperature and entropy

• p-v diagram shows the relationship between pressure and volume

• h-s diagram shows the relationship between enthalpy and entropy

• Vapor cycle includes processes like evaporation, compression, and condensation

• Gas cycle includes processes like compression, expansion, and heat transfer

• Refrigera...read more

The effectiveness equation in heat exchanger determines the efficiency of heat transfer.

• The effectiveness equation compares the actual heat transfer rate to the maximum possible heat transfer rate.

• It takes into account the inlet and outlet temperatures of both fluids and the heat capacity rates.

• The equation is commonly used in designing and optimizing heat exchangers.

• An example of the effectiveness equation is Q/Qmax = (T1-T2)/(T1-T2s), where Q is the actual heat transfer rat...read more

The LMTD equation is used to calculate the temperature difference in heat exchangers.

• LMTD stands for Logarithmic Mean Temperature Difference.

• It is used to calculate the heat transfer rate in heat exchangers.

• The equation is: LMTD = (ΔT1 - ΔT2) / ln(ΔT1 / ΔT2)

• ΔT1 and ΔT2 are the temperature differences between the hot and cold fluids at the inlet and outlet.

• The LMTD equation assumes that the heat transfer coefficient is constant and that the fluids are well mixed.

• It is commonly...read more

The Venturi orifice equation is used to calculate the flow rate of a fluid through a pipe.

• It relates the pressure difference between two points in a pipe to the flow rate of the fluid.

• It is commonly used in industries such as oil and gas, chemical, and water treatment.

• The equation takes into account the diameter of the pipe, the density of the fluid, and the pressure difference.

• It can be used to determine the efficiency of a fluid system and to optimize its performance.

Cavitations in pump is a phenomenon where air bubbles form in the liquid due to low pressure, causing damage to the pump.

• Occurs when the pressure in the pump drops below the vapor pressure of the liquid

• Can cause erosion, noise, and vibration in the pump

• Can be prevented by ensuring proper suction pressure and avoiding high-speed operation

• Examples include water pumps, fuel pumps, and hydraulic pumps