Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

What are the relationships between 1

Status
Not open for further replies.

rfulky

Mechanical
Feb 11, 2003
11
What are the relationships between pressure and temperature in an impact? Is there any equations that can calculate the change in temperature between two materials when they are impacted at a known force?

Thank you
rfulky
 
Replies continue below

Recommended for you

To simplify a very complex phenomenon, the kinetic energy of the impact transforms into elastic and plastic deformation of the material. The elastic portion basically goes into a rebound effect, and the plastic portion becomes heat.
Of course, as the initial temperature increases, so does the plastic/elastic deformation ratio, and hence, heating. And, for a significant impact, the self-heating alters the physical properties during the course of the impact. Thus, requires computer program.

I suggest you look up impact/explosive/detonation welding for equations and modelling. Imagine there are some finite element programs out there.
 
kenvlach

Thanks for your response. If I understand you correctly if there is only elastic deformation taking effect (say in a golf ball-golf club impact) there will be no change in temperature (even slight change) between the two objects.

 
For the equations which describe high impact effects, such as meteroites hitting planets or DU projectiles hitting steel barriers, see Zel'dovich and Raizer "Physics of shock waves and high temperature hydrodynamic phenomena"vol 2 , W.D. Hayes and R.F Probstein (eds) Academic, NY 1967
or Thompson,P A "Compressible Fluid Dynamics" 1st ed 1972 McGraw Hill chap 2.

Basically, the solids behave as a compressible fluid and the effects are a function of the solids' density and speed of sound.
 
whatever energy is absorbed during the impact,assume this energy goes into heat from which you can (knowing mass & Cp of the absorbing body) calculate the temperature rise.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor