HOMEWORK ASSIGNMENT #4
ME 303 FLUID DYNAMICS/ WESTPHAL/ WSU/ FALL 2000
Due: Tuesday 10/17/2000 IN CLASS (submit by conclusion
of class)
FAX to (509)372-7471 -- use the FAX cover or any other cover
page that has "ME 303 R. WESTPHAL" written on it
- Follow the Homework Guidelines for preparing
your submission.
- Don't omit clear identification of a streamline when applying Bernoulli's equation!
- Identification of your CONTROL VOLUME is essential for conservation of momentum applications!
- You are encouraged to work together with other students,
but the work you submit cannot be a machine-produced duplication
of another student's work - it must be an original, but can represent
your version of a collaborative effort.
- Late work not accepted!
The assignment consists of the problems given below. HINT: Use Bernoulli's equation to attack the first four problems; use conservation
of momentum to attack the rest (although you'll need both in problem 5).
Conservation of mass is required for most of these too!
- 5.52 Omit discussion. HINT: first apply conservation of MASS
- 5.63 DISCUSSION: 10 psia is given as the local atmospheric pressure... is that
the static or stagnation pressure?
- 5.65 Omit discussion. NOTE: this device is often called a piezometer tube
- An atmospheric air sampling device is shaped like a funnel: its 80 cm wide "mouth"
faces into the flow, and the 25 cm diameter end where the sensors are located faces
downstream. If this device is mounted beneath a small
aircraft and flown through a still atmosphere at 50 m/s, what will be the air velocity inside
the device at the wide mouth inlet? At the small end? HINT: The inlet velocity is NOT 50 m/s.
For your discussion: what could be done to increase the flow velocity inside the device
for a given flight speed?
- 6.1 NOTE: the 50 kPa pressure is a GAUGE pressure.
- 6.7 omit discussion
- 6.17 omit discussion
- 6.20 Discussion: what would be the effect of increasing the deflection angle from 20 deg to 30 deg?
- 6.28 Discussion: how is the ramjet different than, say, the turbofan of problem 6.90?
- 6.41 omit discussion
- 6.60 omit discussion
- 6.81 Discussion: sketch propulsive force vs. boat speed AND hull drag vs. boat speed - just qualitatively
- 6.90 Discussion: why would one want to have "bypass" air flow?
- 6.93
- 6.99 if the pipe is not rigid, one uses an "effective" bulk modulus: Eeff=Ewater*tpipe*Epipe/(tpipe*Epipe + Dpipe*Ewater)...
also calculate water hammer pressure using Eeff for 6 inch schedule 40 steel pipe. Omit discussion.