Hydrodynamic force of water droplet stated in psi at various mpg

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SUMMARY

The discussion centers on calculating the hydrodynamic force of water droplets impacting a vertical surface, specifically in psi at various speeds such as 20 mph, 40 mph, and 60 mph. Participants explore the relationship between impact force and water droplet density, questioning how light versus heavy rain affects the psi experienced by a motorcycle rider. The complexity of the problem is highlighted by the deformation of water upon impact, which complicates the straightforward application of the force equation FT = mv. Practical experiences shared indicate that impact at higher speeds results in significant discomfort and visibility issues.

PREREQUISITES
  • Understanding of basic physics principles, particularly force and motion.
  • Familiarity with hydrodynamics and fluid dynamics concepts.
  • Knowledge of psi (pounds per square inch) as a unit of pressure.
  • Experience with real-world applications of physics in high-speed environments, such as motorcycling.
NEXT STEPS
  • Research the calculation of impact forces using fluid dynamics equations.
  • Explore the effects of droplet size and density on impact pressure in various weather conditions.
  • Study the relationship between velocity and force in fluid dynamics, particularly the square of velocity effect.
  • Investigate protective measures for motorcyclists against high-speed rain impacts.
USEFUL FOR

This discussion is beneficial for motorcycle riders, physicists, engineers, and anyone interested in understanding the effects of rain on high-speed travel and the associated hydrodynamic forces.

weathergage
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I'm not a student of physics but do have puzzle I am trying to solve. Is there a way to calculate the force of a water droplet impacting a vertical surface stated in psi at various speeds of impact? A more practical way to state the problem would be; what psi will rain impact the chest of a motorcycle rider(sitting tall without a fairing) at 20mph, 40mph, 60mph etc?

The second part of the question is would the psi result change depending on the density (number of water droplets per square inch) of the water? Light rain vs. heavy rain, vs. riding that motorcycle into the vertical surface of a tidal wave?

Thanks in advance for any help. Best Regards, Washley
 
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Can't answer the question but someone likely has taken measurements...
Because water deforms as it hits a solisd surface, the FT =mv relationship is not an obvious one.

The force of wind alone varies as the square of velocity...and I can tell you from boating
experience water hitting you face at about 40 mph stings and without protective eye wear
you can barely see...at around 60 mph...it hurts a lot and you cannot see.edit: no answers but cool pictures here: http://en.wikipedia.org/wiki/Drop_(liquid )
 
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