Homework Assignment 14:
Example Engineering Application of ODEs
Sounding Rocket Performance
Phase 2
Homework Assignment 14
Read:
Refresh your memory by skimming (the guide to the instructor’s or
student’s choice of numerical integration computer programs.)
Work :
We will use the numerical integration computer program once again
Homework Assignment 14 (2)
Programming:
Either recover your own stored program or type in the program given
out by the instructor in reviewing Homework Assignment 6. Program
the equations for air density, drag coefficient and gravity as
described on the next charts.
Output:
Run the numerical integration computer program for each of the
Due: (date)
Homework Assignment 14:
Definition of Key Terms
=
0))/((hRRgg
h
Rocket altitude
=
=
D
T
Thrust (lbs)
Drag(lbs)
More definition of terms
Homework Assignment 14:
Sounding Rocket Equations
Vh
=
Basic equations of motion (as before): More equations for
forces, speed of sound,
etc. in text and in
Supplement to Class
Homework Assignment 14:
Sounding Rocket Equations (2)
Equations given in text and
in Supplement to Class 14A
Notes
Homework Assignment 14:
Sounding Rocket Equations (3)
Graph 1: Air temperature vs altitude
Coordinates:
(altitude (k ft), temp (deg R))
Homework Assignment 14:
Sounding Rocket Equations (4)
Graph 2: Air density reference
altitude vs altitude
)(/
0
hHh
aa e−
=
)(hH
Homework Assignment 14:
Sounding Rocket Parameters
Rocket number
1 2 3
8120 1500
0
W
Initial weight (lbs)
* unique for each student
c
Homework Assignment 14: Student
Parameter Assignments
Rocket 1
Student gas exit speed
#1 4500
#2 4600
Rocket 1
Student gas exit speed
#6 5100
#7 5200
Homework Assignment 14:
Helpful Hints
In look-up tables, remember that data is given in kft, not feet.
*Example logic for User-Defined Function:
If X < 10 then
return 6
else