The state at the beginning of compression of an air-standard Diesel cycle is fixed by p₁ = 100 kPa and T₁ = 310 K. The compression ratio is 18 and the cutoff ratio is 1.5.


Determine:

(a) the maximum temperature, in K.

(b) the pressure at the end of the expansion, in kPa.

(c) the net work per unit mass of air, in kJ/kg.

(d) the percent thermal efficiency.

Air enters the compressor of a simple gas turbine at p1 = 14 lbf/in2, T1 = 520°R. The isentropic efficiencies of the compressor and turbine are 83 and 87%, respectively. The compressor pressure ratio is 16 and the temperature at the turbine inlet is 2500°R. The volumetric flow rate of the air entering the compressor is 9000 ft3/min. Use an air-standard analysis.

Determine the net power developed, in Btu/h.

Air enters the compressor of a simple gas turbine at p1 = 14 lbf/in2, T1 = 520°R. The isentropic efficiencies of the compressor and turbine are 83 and 87%, respectively. The compressor pressure ratio is 16 and the temperature at the turbine inlet is 2500°R. The volumetric flow rate of the air entering the compressor is 9000 ft3/min. Use an air-standard analysis.

Determine the net power developed, in Btu/h.

Q3. 5 kg of water at T = 20° C and P = 7 bar is isobarically heated such that ΔU = 5000 kJ. (i) Find the initial and final volumes (in m3 ). (ii) Find Q and W (in kJ). (iii) Show the initial and final states on p-υ and T-υ diagrams (not to scale), denoting by arrows the direction of the process. Label the ‘f’ (saturated liquid) and ‘g’ (saturated vapor) points. Also, indicate the values of υf and υg on the x-axis of both the p-υ and T-υ diagrams.

Q4. Water inside a closed, rigid tank is cooled from its critical point to a final pressure of 10 MPa. (i) Sketch the process on p-υ and T-υ diagrams. Label the saturated liquid and saturated vapor states. (ii) Find the quality of the water after cooling. (iii) Calculate the heat transfer in kJ/kg.

Q5. Water of mass 1 kg contained in a piston-cylinder configuration is initially in a saturated liquid state (state A) at 10 bar. The water undergoes the following thermodynamic cycle: AB -> The water is heated isobarically until the water is in a saturated vapor state. BC -> The system is then cooled isochorically until the pressure is 1 bar. CD -> The system is further cooled isobarically until υD= υA. DA -> The system is finally heated isochorically back to state A. (i) Sketch this cycle on p-υ and T-υ diagrams (not to scale), using arrows to indicate the direction of each process. (ii) For each of the four states A to D, write down p, T and υ. (iii) For each of the four processes, evaluate the work and heat transfer (in kJ). (iv) What is the thermal efficiency of this power cycle?

Q6 (Bonus). Water of mass 2 kg in a closed, rigid tank is initially in the form of a twophase liquid-vapor mixture. The initial temperature is 50° C. The mixture is heated until the tank contains only saturated vapor at 110° C. (i) Find the initial pressure, in kPa. (ii) Find the work for the process, in kJ. (ii) Find the heat transfer for the process, in kJ.

A layer of cork 6 inch thick is used as layer of thermal insulation in a flat wall. The temperature of the cold side is 40 oF and that of the warm side is 180 oF. The thermal conductivity of the cork at 32 oF is 0.021 Btu/ft-h-oF and that at 200 oF is 0.032. The area of the wall is 25 ft. Estimate the rate of heat transfer through the wall. Answer: 182 Btu/hr

Design a refrigerator working on propane ammonia and R407C refrigerant and producing -20K, -10K and O K temperature during steady state operation....

carryout experimental validation using appropriate software.

write energy and exergy equation in Fortran 77 only...
plot graph in scilab....

Towers for support of the electric lines are made of wood (as-grown or laminated), steel or aluminum (either lattice structures or tubular poles), concrete, and occasionally reinforced plastics. What would you choose, and what constraints would you think must be met to select the best material?

and what formulas should be used to choose the best material?

while servicing a pair of aluminum cylider heads:technecian a says if needed,both heads must be machined equally and the same amount of material removed from each.technecian b says replace bboth heads if warpage exceeds the specified allowable amount.who is correct?

determine the cutting speed and calculate spindle RPM for driiling a 1.5" diameter hole ins AISI-SAE 1020 steel with a brinell hardness of 125 to 175

A gas with cp = 0.950 kJ/kg-K enters an insulated nozzle at 30^oC and a velocity of 8 m/s. The gas exits at a velocity of 100 m/s. Assuming constant specific heats and ideal gas behavior, what is the exit temperature of the gas?

An alloy of magnesium and lead is 50% lead by weight. A) convert this alloy to an equivalent atomic percentage. B) Convert this alloy to an equivalent volume percentage

Complete exercise 9.20 from the text.

(a) Create a function called polygon that draws a polygon in a polar plot. Your function should have a single input parameter – the number of sides.

(b) Use a for loop to create a figure with four subplots…You should use the function you created in part (a) to draw each polygon. Use the index parameter from the for loop to specify the subplot in which each polygon is drawn, and in an expression to determine the number of sides used as input to the polygon fuction.

For help with the algorithm to draw regular polygons, consult problem 8.17 To be clear, the polygon() function should only draw one polygon, as specified by the number it receives as a parameter.

A second function or script should have the for loop, call subplot() to indicate where to create a plot, and call polygon() to actually create the plot.

Additional notes include:

1. There must be some weird junk on the internet because many previous students have tried to use some gibberish with rand() and cumsum() that does not create triangles, squares, etc. Do not repeat their mistakes.

2. Never clear variables at the start of a function!

3. A for loop with just one number is a waste of typed characters.

4. The instructions never mention prompting the user for a number.

5. You must call subplot before you plot anything that is supposed to go into a subplot.

6. Things that only need to be done once should not be inside a loop, such as set(gcf, …). The only things that should be inside a loop are the things that must be repeated.

7. If you copy and paste a few lines, especially more than once, there is probably a better way.

and here's what I did so far, it needs to be fixed according to note number 4 and additional corrections

%% 9.20 (a) create a function called polygon in a polar plot
function [p] = polygon(n)
n = input('Enter the number of sides: ');
theta = 0: 2*pi/n : 2*pi;
r = ones(1, length(theta));
subplot(2, 2, n-2); polar(theta, r);
end
% (b) use a for loop to create figure with four subplots
function polygon
for n = 3: 1: 6
polar(theta, r)
end

end

Thanks

Determine the force vs reduction in height curve in open-dye forging of a cylindrical, annealed copper specifmen 10mm high and 25mm in diameter, up to a reduction of 50% for the following cases:

a) no friction between the flat dies and the specimen

b) u=0.10

c) u=0.30

Ignore barreling and use average pressure formulas.

Then, calculate the work done and the temperature rise in the specimen for each case, assuming the process is adiabatic and and the temperature is uniform throughout the specimen.

Use the following values:

K=315KPa

n=0.54

Cp=380J/kgK

p(rho)= 8970k/m^3

Air flows through a pipe that has a length of 45 m with an inside diameter of 0.025 m. The Mach number of the flow exiting the pipe is 0.26, with a static pressure of 1 atmosphere and a temperature of 300 K. If the friction factor is assumed constant at 0.007, calculate the Mach number, static pressure, static temperature and total pressure at the entrance.

P2) Ethane in a rigid vessel is to be heated from 0.5MPa and 40 °C to 290 °C. Using the compressibility chart, determine the final pressure.