Influence of a humidor on the aerodynamics of baseballs

  • Context: Graduate 
  • Thread starter Thread starter marcus
  • Start date Start date
  • Tags Tags
    Aerodynamics
Click For Summary

Discussion Overview

The discussion centers on the influence of humidity on the aerodynamics of baseballs, particularly in relation to their storage in humidors. Participants explore the effects of different humidity levels on the physical properties of baseballs, including their mass, diameter, elasticity, and overall performance in gameplay. The conversation touches on theoretical implications and practical applications in the context of baseball played at Coors Field.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants suggest that drier baseballs may curve more effectively and travel shorter distances when hit, potentially favoring pitchers.
  • Others argue that damper baseballs might favor batters due to their perceived softness and ability to absorb impact.
  • A participant notes that elasticity and surface roughness are likely affected by humidity, which could influence performance.
  • One participant expresses surprise that the elasticity of baseballs was not measured in the original study, indicating it as a significant factor.
  • Another participant mentions that older baseballs stored without humidors were falling below regulation weight due to drying, suggesting a need for standardized storage conditions across parks.
  • A reference is made to previous studies on elasticity as a function of humidity, indicating ongoing research in this area.

Areas of Agreement / Disagreement

Participants express differing views on whether drier or damper baseballs are advantageous for pitchers or batters, indicating that the discussion remains unresolved with multiple competing perspectives.

Contextual Notes

Limitations include the lack of measurements for elasticity in the initial study and the potential variability in storage conditions across different baseball parks, which may affect the outcomes discussed.

marcus
Science Advisor
Homework Helper
Gold Member
Dearly Missed
Messages
24,752
Reaction score
795
http://arxiv.org/abs/0712.0380
Influence of a humidor on the aerodynamics of baseballs
Edmund Meyer, John Bohn
17 pages, 6 figures
(Submitted on 3 Dec 2007)

"We investigate whether storing baseballs in a controlled humidity environment significantly affects their aerodynamic properties. To do this, we measure the change in diameter and mass of baseballs as a function of relative humidity (RH). We then model trajectories for pitched and batted baseballs to assess the difference between those stored at 30% RH versus 50% RH. The results show that a drier baseball may be expected to curve slightly more than a humidified one, and that the drier ball will also likely travel slightly less far when batted. We discuss consequences of these results for baseball played at Coors Field in Denver, where baseballs have been stored in a humidor at 50% RH since 2002."

I would surmise that drier balls favor the pitcher,
if they indeed take a curve better and, when hit, don't go as far.

Conversely, damper balls might be supposed to favor the batter.

EDIT: I got the effect backwards. Pitchers like the damper balls.

I was under the impression that humidors were originally invented to store cigars, back in the days of serious cigar-smoking. Here is another use for humidors.
 
Last edited:
Physics news on Phys.org
Elasticity/resiliency is one property/factor affected by humidity, the other is likely surface roughness.
 
I would have assumed the humid ball would be softer, therefor absorbing more of the impact from the bat, which would result in the ball not traveling as far as a harder, dry ball.

I assume the balls are kept in a humidor to prevent the leather from cracking?

Edit: Ah, the story behind the ball humidor, a pair of leather boots.

http://www.usatoday.com/sports/baseball/nl/rockies/2007-10-09-humidor2-coors_N.htm
 
Last edited:
Pretty interesting story in Evo's link. They mention that the older balls stored at the park before humidors were actually falling under regulation weights due to the drying! I wouldn't have thought they would have THAT much water content in the balls. It makes you think that maybe storage conditions should be standardized across all parks. There are enough other variables that the storage of the balls shouldn't be one of them when it's something much easier to control (and how many of the team owners would be storing their cigars alongside the balls? :biggrin:)
 
The elasticity as a function of humidity had already been studied, in The Physics Teacher, Vol. 42, p.89 (Sept. 2004).