Diesel fuel $\left(\mathrm{C}_{12} \mathrm{H}_{26}\right)$ at $77^{\circ} \mathrm{F}$ is burned in a steadyflow combustion chamber with 20 percent excess air that also enters at $77^{\circ} \mathrm{F}$. The products leave the combustion chamber at $800 \mathrm{~R}$. Assuming combustion is complete, Find the required mass flow rate of the diesel fuel to supply heat at a rate of $1800 \mathrm{~Btu} / \mathrm{s}$.

A gas-turbine power plant operates on a modified Brayton cycle shown in the figure with an overall pressure ratio of $\delta$. Air enters the compressor at 0 degree C and 100kPa. The maximum cycle temperature is 1500K. The compressor and the turbines are isentropic. The high-pressure turbine develops just enough power to run the compressor. Assume constant properties for air at 300K with $c_U=0.718 \mathrm{~kJ} / \mathrm{kg} \cdot \mathrm{K}, c_p=1.005 \mathrm{~kJ} / \mathrm{kg} \cdot \mathrm{K}, R=0.287 \mathrm{~kJ} / \mathrm{kg} \cdot \mathrm{K}, k=1.4$

(a) Sketch the T-s diagram for the cycle. Label the data states.

(b) Determine the temperature and pressure at state 4 , the exit of the high-pressure turbine.

(c) If the net power output is 200MW, determine the mass flow rate of the air into the compressor in kg/s.

Steam enters an adiabatic turbine at $7 \mathrm{~MPa}, 600^{\circ} \mathrm{C}$, and $80 \mathrm{~m} / \mathrm{s}$ and leaves at $50 \mathrm{~kPa}, 150^{\circ} \mathrm{C}$, and $140 \mathrm{~m} / \mathrm{s}$. If the power output of the turbine is $6 \mathrm{~MW}$, Find $(a)$ the mass flow rate of the steam flowing through the turbine and $(b)$ the isentropic efficiency of the turbine.

Methane $\left(\mathrm{CH}_{4}\right)$ is burned completely with the stoichiometric amount of air during a steady-flow combustion process. If both the reactants and the products are maintained at $25^{\circ} \mathrm{C}$ and $1 \mathrm{~atm}$ and the water in the products exists in the liquid form, Find the heat transfer from the combustion chamber during this process. What would your answer be if combustion were achieved with $100$ percent excess air?

What does the dew-point temperature of the product gases represent? How is it determined?

Propane fuel $\left(\mathrm{C}_{3} \mathrm{H}_{8}\right)$ at $25^{\circ} \mathrm{C}$ is mixed steadily with $50$ percent excess air at $500^{\circ} \mathrm{C}$ in an atmospheric pressure combustor. Combustion products leave at $1500^{\circ} \mathrm{C}$, and the volumetric flow rate of the air is $1 \mathrm{~m}^{3} / \mathrm{s}$. Find the rate of heat transfer in this combustor.

$\mathrm{n}$-Octane gas $\left(\mathrm{C}_8 \mathrm{H}_{18}\right)$ is burned with $100$ percent excess air in a constant pressure burner. The air and fuel enter this burner steadily at standard conditions and the products of combustion leave at $257^{\circ} \mathrm{C}$. Calculate the heat transfer, in $\mathrm{kJ} / \mathrm{kg}$ fuel, during this combustion.

In the planetary gear system shown, the radius of gears $A, B, C$, and $D$ is $a$ and the radius of the outer gear $E$ is $3 a$. Knowing that the angular velocity of gear $A$ is $\omega_A$ clockwise and that the outer gear $E$ is stationary, determine $(a)$ the angular velocity of each planetary gear, $(b)$ the angular velocity of the spider connecting the planetary gears.

Propane fuel $\left(\mathrm{C}_{3} \mathrm{H}_{2}\right)$ is burned with an air-fuel ratio of 25 in an atmospheric pressure heating furnace. Determine the heat transfer per kilogram of fuel burned when the temperature of the products is such that liquid water just begins to form in the products.

Consider a complete combustion process during which the reactants enter the combustion chamber at $20^{\circ} \mathrm{C}$ and the products leave at $700^{\circ} \mathrm{C}.$ Combustion is achieved with (a) 100 percent theoretical air, (b) 200 percent theoretical air, and (c) the chemically correct amount of pure oxygen. For which case will the amount of heat transfer be the lowest? Explain.

Consider a complete combustion process during which both the reactants and the products are maintained at the same state. Combustion is achieved with (a) 100 percent theoretical air. (b) 200 percent theoretical air, and (c) the chemically correct amount of pure oxygen. For which case will the amount of heat transfer be the highest? Explain.

(a) Briefly describe sandwich panels. (b) What is the prime reason for fabricating these structural composites? (c) What are the functions of the faces and the core?

(a) What is the distinction between cement and concrete? (b) Cite three important limitations that restrict the use of concrete as a structural material. (c) Briefly explain three techniques that are used to strengthen concrete by reinforcement.

Consider a 3-kW hooded electric open burner in an area where the unit costs of electricity and natural gas are $0.09/kWh and$1.10/therm, respectively. The efficiency of open burners can be taken to be 73 percent for electric burners and 38 percent for gas burners. Determine the amount of the electrical energy used directly for cooking, the cost of energy per “utilized” kWh, and the contribution of this burner to the design cooling load. Repeat the calculations for the gas burner.