A mixture with 70% quality at 500 kPa is heated isothermally until its pressure is 300 kPa. Find the heat added during the process. @ 600 kPa: sf = 1.8607 kJ/kg-K sfg = 4.9606 kJ/kg-K @ 300 kPa and 151.86°C: s = 7.0888 kJ/kg-K

Find the enthalpy of water at 212°F and 14.7 psi if the dryness factor is 30%. Use the approximate enthalpy formula of liquid.

Steam at 2 MPa and 250°C in a rigid cylinder is cooled until the quality is 30%. Find the heat rejected from the cylinder. @ 2 Mpa and 250°C: υ = 0.11144 m3/kg u = 2679.6 kJ/kg @ 2 Mpa, (saturated): υf = 0.0011767 m3/kg υg = 0.09963 m3/kg uf = 906.44kJ/kg ug = 1693.8 kJ/kg

A steam generator with economizer and air heater has an overall draft loss of 25.78 cm of water. If the stack gases are at 177°C and if the atmosphere is at 101.3 kPa and 26°C, what theoretical height of stack in meters is needed when no draft fan is used? Assume that the gas constant for the flue gases is the same as that for air.

A Pelton type turbine has 25 m head friction loss of 4.5 m. The coefficient of friction head loss (Morse) is 0.00093 and penstock length of 80 m. What is the penstock diameter?

A tank contains exactly one kilogram of water consisting of liquid and vapor in equilibrium at 1 MPa. If the liquid contains one-third and the remaining is vapor of the volume of the tank, what is the enthalpy of the contents of the tank? @ 1MPa: υf = 0.0011273 m3/kg υfg = 0.19444 m3/kg hf = 762.81 kJ/kg hfg = 2015.3 kJ/kg

A throttling calorimeter is connected to a desuperheated steam line supplying steam to the auxiliary feed pump on a ship. The line pressure measures 2.5 MPa. The calorimeter pressure is 110 kPa at 150°C. Determine the entropy of the steam line. @ 110 kPa and 150°C: h2 = 2775.6 kJ/kg @ 2.5 MPa: hf = 962.11 kJ/kg hfg = 1841 kJ/kg sf = 2.5547 kJ/kg-K sfg = 3.7028 kJ/kg-K

In a gas unit, air enters the combustion chamber at 550 kPa, 227°C and 43 m/s. The products of combustion leave the combustor at 511 kPa, 1004°C and 180 m/s. Liquid fuel enters with a heating value of 43,000 kJ/kg. For fuel-air ratio of 0.0229, what is the combustor efficiency in percent?

A steam pipe having a surface temperature of 250°C passes through a room where the temperature is 27°C. The outside diameter of the pipe is 100 mm and emissivity factor is 0.8. Calculate the radiated heat loss for 3 m pipe length.

Predict the pressure of nitrogen gas at T = 200 K and υ = 0.00385 L/g and b = 0.00141 L/g; a = 0.178 L2-kPa/g2. Use Van der Waals equation.

An insulated rigid tank initially contains 1.5 lb of helium at 80°F and 50 psia. A paddle wheel with power rating of 0.02 hp is operated within the tank for 30 min. Determine the final temperature.

A piston-cylinder device whose piston is resting on top of a set of stops initially contains 0.50 kg of helium gas at 100 kPa and 25°C. The mass of the piston is such that 500 kPa of pressure is required to raise it. How much heat must be transferred to the helium before the piston starts rising?

A Francis turbine is to be operated at a speed of 600 rpm and with discharge of 4 m3/s. If r1= 0.6 m, β = 110°, and the blade height B is 10 cm, what should be the guide vane angle α1 for nonseparating flow condition at the runner entrance?

Compute the amount of condensate formed during a 10 minute warm-up of 180 meter pipe conveys the saturated steam with enthalpy of vaporization, hfg = 1947.8 kJ/kg. The minimum external temperature of pipe is 2°C. The final temperature of pipe is 195°C. The specific heat of pipe material is 0.6 kJ/kg-°C. The specific weight is 28 kg/m.

A single acting compressor has a volumetric efficiency of 89%, operates at 500 rpm. It takes in air at 100 kPa and 30°C and discharges it at 600 kPa. The air handled is 8 m3/min measured at discharged condition. If compression is isentropic, find the effective mean pressure in kPa.

A fan draws 1.42 m3 per second of air at a static pressure of 2.54 cm of water through a duct 300 mm diameter and discharges it through a duct of 275 mm diameter. Determine the static fan efficiency if total fan is 75% and air is measured at 25°C and 760 mm Hg.

An air compressor has a suction volume of 0.35 m3/s at 97 kPa and discharges at 650 kPa. How much power is saved by the compressor if there are two stages?

The initial condition of air in an air compressor is 98 kPa and 27 °C and discharges air at 450 kPa. The bore and stroke are 355 mm and 381 mm, respectively with percent clearance of 8% running at 300 rpm. Find the volume of air at suction

An ideal Brayton cycle has a net work output of 150 kJ/kg and backwork ratio of 0.4. if both the turbine and the compressor had an isentropic efficiency of 80%, the net work output of the cycle would be?

To what height will a barometer column rise if the atmospheric conditions are 13.9 psia and 68°F and barometer fluid is ethyl alcohol? Note: @ 68°F; Pv =138.5 lbf/ft^3 and specific gravity of 0.79 for ethyl alcohol:

A model pump delivering water at 180°F (γ = 60.6 lb/ ft^3; pvapor = 7.54 psia) at 900 gpm and 2500 rpm begins to cavitate when the inlet pressure and velocity are 13 psia and 22 fps. Find the required NPSH of a prototype which is 4 times larger and runs at 1100 rpm.

Saturated vapor ammonia at -16°C (hT = 1442.60 kJ/kg) leaves the evaporator and enters the compressor at -6°C (h1 = 1465 kJ/kg). The refrigerant leaves the condenser as saturated liquid at 40°C (h4 = 390.6 kJ/kg) and enters the expansion valve at 35°C (h5 = 366.1 kJ/kg). Heat rejected from the condenser amount to 50 kW. The work to compressor is 208 kJ/kg, while the heat loss from compressor is 33 kJ/kg. If 95 kJ/kg of heat are lost in the piping between the compressor discharge and condenser inlet, determine the refrigerating capacity of the system