Fluid Mechanics - True or False

1) Reynolds number represents the ratio of viscous force to the inertia force.
2) The entrance length (Le) for turbulent flow is greater than that for laminar flow for the same pipe diameter.
3) Increase the fluid viscosity leads to decrease the turbulence.
4) For laminar steady flow between parallel fixed plates, the pressure drop increase with increasing the thickness of the fluid layer between them.
5) For laminar steady flow for pipe, the pressure drop increase with increasing the pipe diameter.
6) For the same Reynolds number, friction factor for steady laminar flow between parallel plates is greater than that for pipe flow.
7) For turbulent flow, the thickness of viscous sublayer is greater than the thickness of inertial sublayer.
8) Darcy -Weisbach equation can be used for calculating the head of losses for both laminar and turbulent flow.
9) Minor losses important only for turbulent flow.
10) Minor losses for entrance flow conditions is less than that for exit flow conditions.

Only state if its False or True for each point.

A diesel cycle operates at and receives 400BTU of energy from the combustion process. The hot air standard is k=1.3. The diesel engine receives air at a pressure of 14.5psia, 90°F, and 0.55lb. What is the mean effective pressure of the engine? The cut-off ratio is 12% of the volume displacement and the percent clearance is 8%.

A rigid sealed tank contains 0.5 kg R-410a at 0^oC with specific volume 0.01m³/kg. The pure substance R-410a is now heated to a room temperature of 25^oC.

a. Find the volume of R-410a in the tank.              [2]

b. Find the final pressure R-410a in the tank          [2]

c. Find the process heat transfer.

A Diesel cycle engine is analyzed using the air standard method. Given the conditions at state 1, compression ratio (r), and cutoff ratio (rc) determine the efficiency and other values listed below.

Note: The gas constant for air is R=0.287 kJ/kg-K.

Given Values

T1 (K) = 338

P1 (kPa) = 130

r = 14.5

rc = 1.25

a) Determine the specific internal energy (kJ/kg) at state 1.

b) Determine the relative specific volume at state 1.

c) Determine the relative specific volume at state 2.

d) Determine the temperature (K) at state 2.

e) Determine the pressure (kPa) at state 2.

f) Determine the specific enthalpy (kJ/kg) at state 2.

g) Determine the temperature (K) at state 3.

h) Determine the pressure (kPa) at state 3.

i) Determine the specific enthalpy (kJ/kg) at state 3.

j) Determine the relative specific volume at state 3.

k) Determine the relative specific volume at state 4.

l) Determine the temperature (K) at state 4.

m) Determine the pressure (kPa) at state 4.

n) Determine the specific internal energy (kJ/kg) at state 4.

o) Determine the net work per cycle (kJ/kg) of the engine.

p) Determine the heat addition per cycle (kJ/kg) of the engine.

q) Determine the efficiency (%) of the engine.

2.2 kW of power will be trasnmitted via chain-sprocket system. Rotational speed of input shaft is 20 rpm. Required approximate rotational speed of input shaft is 20 rpm. Required approximate rotational speed for the out shaft is 7 rpm. Approximate distance between center lines of input and output shafts should be 900 mm. This chain-sprocket system is used for an elevator and it is asked to use single or multiple DIN 8187 chain with 31.75 mm pitch.

a) Calculate number of teeth on sprocket, which is on output shaft, is number of teeth on the sprocket on input shaft is 19.

b) Calculate input power for selection of chain and select the appropriate chain type.

c) Calculate pitch circle diameters of driving and driven sprockets, linear velocity of chain, length of chain, (number of chain links), and exact center line distance between driving and driven sprocket.

d) Calculate factor of safety of the selected chain.

b) A 15 MW gas turbine plant operates with a two-stage compression and a two-stage

expansion. The high-pressure turbine (HPT) drives both low-pressure compressor

(LPC) and high-pressure compressor (HPC). A low-pressure turbine (LPT) is connected

to a generator for electricity generation The overall pressure ratio is 16/1 and the

maximum cycle temperature, which is at the inlet of the HPT, is 900°C. The gases

leaving the HPT are reheated to 850°C before entering the LPT. Both compressors have

equal pressure ratios with an intercooler between the stages, and the intercooling

process is complete. Air enters the LPC at a temperature and pressure of 27°C and

100 kPa respectively. The exhaust gases leaving the LPT are passed through a heat

exchanger to heat the air leaving the HPC. Thermal ratio of the heat exchanger is 0.78.

The isentropic efficiencies for both compressors and turbines are 85%. The mass of fuel

injected is negligibly small. Assuming that the kinetic and potential energy changes are

negligibly small,

i. sketch the cycle on a temperature-entropy (T-s) diagram,

ii. determine the required air mass flow rate for the gas turbine, kg/s,

iii. determine the thermal efficiency of the power plant, %, and

iv. determine the work ratio.

For air, take cpa = 1.005 kJ/kg.K and γa = 1.40

For gas, take cpg = 1.14 kJ/kg.K and γg = 1.35

Your task is to build a wastewater treatment plant to handle all of the domestic wastewater produced by a housing estate. Using population equivalent, PE = 65000, design, describe and calculate briefly the sizes of all the unit processes in the treatment plant that are going to be built. You may assume the value that is not given.

a-Arrange in a table the number of phases that can be observed at R.T in the range starting from zero to 6.67%C in an "Equilibrium Phase Diagram" and the corresponding three of the mechanical properties.b- Explain with examples the solid-solution, eutectic and peritectic observed phases.c- Draw the .microstructure of each phase

Following readings are obtained in a roundness tester

(5,0) (6,60). (4,120) (3,180), (2,240) (3,300)

Compute Least Square Limacon Circle parameters.

Compute roundness error.

Please, I want a paragraph about ABS materiel, with a table of properties of ABS.

I need it in an experimental measurement and techniques project. NO PLAGIARISM PLEASE

Q1: answer the following without explaining anything wanted to compare my answers with an expert, please do it immediately, I have no time:

2. A___________ instrument may be used to trip an inductive proximity sensor if needed

1. Liquid
2. Gaseous
3. Reflective
4. Metallic

3. A non-metallic object displaces the normal_________ air, between the capcitive plates when the object enters the electrostatic field:

1. Dry
2. Lonized
3. Dielectric
4. Moist

4. Some Hall effect sensors require the mounting of a separate _______ to trigger the device

1. Magnet
2. Brace
3. Power supply
4. LED

5. ___________ oscillator circuits produce a more accurate output frequency than pure LC or RC components alone.

1. Capacitor
2. Crystal
3. Resistor
4. Inductor

6. Mount a capacitive proximity sensor so that it is pointed __________ the target location.

1. Above
2. Away from
3. Toward
4. Below

7. Hall Effect sensors Generate very small internal_______________

1. Currents
2. Resistances
3. Voltages
4. Temperatures

8. Inductive proximity sensors can detect___________ metals, such as aluminum, at shorter distances than ferrous metals because these targets are not easily magnetized.

1. Nonferrous
2. Oxidized
3. Shiny
4. Flat

1. Mount a photoelectric sensor so that it’s pointed _________ the target location.

1. Toward
2. Above
3. Away from
4. Below

Consider a very small particle of mass, m, dropped in a fluid. The particle experiences a drag force, FD. The constant that relates the drag force to the velocity V is K. Determine the distance covered as the partcile accelerate from rest to 50 percent of its terminal velocity, Vt, in terms of K, m, and acceleration due to gravity, g.

Hello! do you know how to save the output file of result in Ansys fluent 15.0 ? Because I want to save the number of nodes with the values of the velocity, pressure, temperature,etc. After I completed each task, so I want to save all these data and I want to compare the results with the next calculation. Thank you in advance! really appreciate you help! I will thumb you up!