Chapter 7, Problem 7.37P

Five kilogram of steam is initially at 1MPa and y=40% inside the piston cylinder. There is a 50C superheat introduced in steam isopiestically. Find the change of entropy of the steam.

A nozzle is a device for measuring the velocity of flow. At inlet to a nozzle the enthalpy is 3026 kJ/k, the velocity is 60 m/s. At exit from the nozzle the enthalpy is 2790 kJ/kg. The nozzle is horizontal and there is a negligible heat loss from the nozzle. Find he velocity at nozzle exit The inlet area is 0.1 m2 and the specific volume at the inlet is 0.19 m²/s, find the mass flow rate • f the specific volume at the nozzle exit is 0.5 m²/kg, find the exit area of the nozzle (688m/s) (0.36kg/s) (0.0299m2) Air and fuel enter a furnace used for home heating. The air has an enthalpy of 320 kJ/kg and the fuel has an enthalpy of 43027 kJ/kg. The gases leaving the furnace has an enthalpy of 616 kJ/kg. There are 17 kgair / kgfuel, water circulated through the wall furnace receiving heat. The hose required 17.02 kW of heat, what is the fuel consumption per day. (41 kg/day)

Air at the rate of 14kg/sec expands from 3bar, 1500C, 0.1m3 to 1 bar reversibly and adiabatically. Find the exit temperature and power developed. If the heat is given to the system 1200J. Find out the change in internal energy

A nozzle is a device for increasing the velocity of a steadily flowing stream of fluid, At the inlet to a certain nozzle the enthalpy of the fluid is 3025 kJ/kg and the velocity is 60m's. At the exit from the nozzle the enthalpy is 2790 kJ/kg. The nozzle is horizontal and there is negligible heat loss from it. (a) Find the velocity at the nozzle exit. (b) If the inlet area is 0.1 m’and the specific volume at the inlet is 0.19 m²/kg, find the rate of flow of fluid (C) If the specific volume at the nozzle exit is 0.5 m kg, find the exit area of the nozzle. Dr. Hameed J. Khalaf Subject Lecture

An adiabatic turbine has an efficiency of 90%. If air is compressed from 1100kpa and 227 degree Celsius to 101kpa. Find the work done and final temperature. Sketch process on T-S diagram.

A 2.5 kg copper block at 200 °C and 5 kg aluminum block at 20 °C come in thermal contact. Find the final temperature and the entropy generated. Consider both blocks together as your system and assume no heat loss to the surroundings.

The power of a steam turbine in a thermal power plant is 60 MW. Water vapor enters the turbine at 3MPa pressure, 4000C temperature and 50 m / s speed, 10 kPa pressure, 0.9 dry degree and 200 m / s speed leaves the turbine. Considering the turbine as adiabatic; 1-Find the mass flow of steam 2-Find the turbine outlet cross-sectional area, its ratio (A2 / A1) to the inlet cross-sectional area.

Find the mass of water that can be cooled from 26°C to-10°C from a 20 tons refrigeration system for 14 hrs.

An elastic balloon behaves such that pressure is proportional to diameter and the balloon contains 0.5 kg air at 200 kPa and 300 The balloon is momentarily connected to an air line at 500 kPa and 1000C. Air is let in until the volume doubles, during which process there is a heat transfer of 50 kJ out of the balloon. Find the final temperature and the mass of air that enters the balloon.