If you designed a Tennis ball collecting robot

Explain:

a) Which sensor(s) would you use. Why?

b) Which computing unit would you use? Why?

c) Which actuator would you use? Why?

d) Draw the block diagram of the system.

e) Draw the flow chart of the control software.

1. What is screw pump?

2. working principle of screw pump.

3. screw pump test rig

4. procedure

5. general use

6. identify its accuracy, precision and time respond in getting a reading.

7. the advantage and disadvantage of screw pump.

A pump operating at steady state receives 1.5 kg/s of liquid water at 50^oC, 1.5 MPa. The pressure of the water at the pump exit is 14 MPa. The magnitude of the work required by the pump is 25.2 kW. Stray heat transfer and changes in kinetic and potential energy are negligible.

Determine the work required by a reversible pump operating with the same conditions, in kW, and the isentropic pump efficiency.

Design a chain drive for a Centrifugal Pump to be driven by a Steam Turbine. The input speed will be 1100 RPM, and the desired output speed is 350 RPM. The conveyor requires 20.0 hp. What type of lubrication will be needed?

Inside a boiler with a volume of 0.5 m, there is wet steam with a half volume of water at 140 kPa pressure. As a result of giving heat at constant pressure, after half of the water is vaporized, heat is continued until the pressure in constant volume is 1 MPa. Then, after giving heat at constant pressure, according to the temperature is 400 ° C; Show the temperature, pressure, volume, internal energy, enthalpy and dryness levels in a table during state changes.

b) Show the state changes in P-v and T-v diagram.
c) Find the work and heat transition after the state changes.
d) Find the required amount of fuel (natural gas, coal, fuel oil) for the heat given after the state changes by making the necessary assumptions.

Exhaust gases having properties similar to dry air enter a thin-walled square duct exhaust stack at 500 ºC. The stack is made of galvanized iron and is 20 m tall and 0.25 m side. If the gas flow rate is 0.5 kg/s and the stack surface has the outside ambient temperature of 10 ºC estimate:

a) the outlet temperature of the exhaust gas

b) the heat transfer coefficient

c) the rate of heat transfer

d) the pressure drop

A gas turbine air- standard cycle operates between a low pressure of 14.7 Psia and a high pressure of 60 Psia. The temperature of the gas at the inlet to the compressor and turbine are 60 and 1000 respectively. If 40,000 ft3 /min. of air enter the compressor and assuming k=1.41, compute:

a) The theoretical net power output, and

b) The air – standard thermal efficiency

An insulated rigid tank having a 0.2 m3 volume initially contains air at 400 kPa and 313 K. The amount of paddle-wheel work done on the system is 200 kJ. Calculate the nearest value of entropy change

a. 0.66 kJ/K

b. 0.88 kJ/K

c. None

d. 0.44 kJ/K

e. 0.33 kJ/K

A refrigerator removes heat from a refrigerated space at -6°C and rejects it to an environment at 30°C. If the temperature in the cooled area is reduced to - 18°C, determine the minimum percentage increase in the work required for the same amount of energy from which the Carnot refrigerator is removed.

a. 53

b. 33

c. 93

d. 13

e. 73

A single stage double acting air compressor having a clearance of 4% takes in air at 14.2 Psia and 60 and compresses it to 200 Psia. If the weight of the air compressed per minute is 50 lbs. and n = 1.35, compute: a) The work required to compress the air per minute b) The piston displacement if the compressor operates at 100 RPM c) The volume of free air measured at 14.7 Psia atmospheric pressure.

Complete the following statements about the crystallinity in polymers by choosing the right answers in the [box].

Most thermoset polymers are [amorphous/crystalline] .

Some thermoplastic polymers are semi-crystalline, meaning they have both higher density  [amorphous/crystalline] regions and lower density  [amorphous/crystalline] regions.

In many semi-crystalline polymers, the polymer chains fold into [lamellae/spherulite] structures which can be part of a larger  [lamellae/spherulite] structure which is formed around a nucleation site.

In semi-crystalline polymers, the glass transition temperature is where there is an increase in the ability of the polymer chains to move in the  [amorphous/crystalline] regions. The melting point is where the  [amorphous/crystalline] regions turn into a liquid.

Explain in general in which area you would apply similarity concept along your career as
a mechanical engineer. How will it benefit you and your organisation.

A three-dimentional flow velocity can be measured by using various method. Please name
two devices that use a probe and two sophisticated devices without a probe usage for the
three-dimentional flow velocity measurement.

The terrace roof of a building at sea level is planned to have a rectangular floor area with dimensions of 10 m and 20 m. The prevailing wind speed in winter is u∞=25 km/h, and air temperature is assumed to be T∞=0°C. Considering that the outer surface temperature of the building is To=10°C, how should the building be positioned with respect to the prevailing wind direction to minimize the heat loss from the roof?