THE IDIOT AND THE $130 COOLER. AN EXPERIMENT IN HEAT TRANSFER.

Introduction

Riding long distances on a motorcycle exposes the rider to the effects of dehydration, including thirst, dark colored urine, headache, fatigue, dry mouth, and loss of strength or stamina. To mitigate the effects of dehydration, Long Distance Riders (LDR's) have used a variety of cooler, bladders, drink holders, and other insulated liquid containers to have cool, refreshing water available while riding their motorcycles.
One popular item is the Coleman 1 Gallon Cooler, typically available in the $8-10 range from various stores and online retailers. In the author's experience, this cooler is adequete for most LDR's, unless faced with an extremely hot day, in which case the LDR could be forced to stop their motorcycle to refill the cooler with ice, or suffer through the misery of consuming warm or tepid water.
In an attempt to enhance his motorcyling experience, the author hypothesizes that a cooler from Yeti, while significantly more expensive ($130), will provide a decreased rate of heat transfer, thus obviating the need for the LDR to stop for ice during the day.

Materials

Taylor Digital Probe Thermometer, Item #9848BEFDA, Operating Range (-40F - 450F).

Yeti Rambler 1 Gallon Jug, Item # YRAMOGJ.

Coleman 1 Gallon Cooler, Item # 3000000731.

One random 8 pound bag of commercially prepared ice.

Methods

On August 29, 2017, 0600, the author intends to fill both coolers with ice and water, record the temperature of the contents, seal the coolers, and place the coolers in a sunlit area. Ambient temeratures are expected to be 55F - 73F during the day. At 1800, the coolers will be opened,  temperatures recorded, and observations made on the contents.  In the event that ice remains in one or more of the coolers, the experiment will be carried forward into the following day with additional observations at 0600 and 1800 on August 30, 2017.

Technique

On the morning of August 29, 2017, each cooler was carefully inspected by the author. Each cooler was noted to be in good, usable condition with a properly fitting lid.

3 pounds of the commercially prepared ice was added to each cooler. 

64 oz of water was added to each cooler.

August 29, 2017, 0600, 33.1F.

August 29, 2017, 0600, 33.1F

Coolers positioned on heat absorbing surface. 

Following inspection, each cooler was filled with 3 pounds of the commercially prepared ice and 64 oz of water. The temperature of the ice + water mixture was noted for each cooler, and the lids were sealed on the coolers. At 0600, both sealed coolers were placed on a flat, heat absorbing surface (author's hot tub cover). The heat absorbing surface was chosen to simulate the effects of having a cooler located adjacent to a hot motorcycle all day.

The temperature in both coolers was noted to be 33.1F.

At 1800 on August 29, 2017, the coolers were opened, temperatures taken, and the coolers were sealed, and placed back in their respective positions.

After 12 hours outdoors, the temperature of the ice and water mixture in the Yeti cooler remained at 33.1F. During the same period, the temperature of the ice and water mixture in the Coleman cooler rose to 37.0F. A qualitative visual analysis of the ice and water mixture in both coolers reveals a significant difference in both the size and quantity of ice cubes remaining between the two coolers.

August 29, 2017, 1800, 33.1F

August 29, 2017, 1800, 37.0F

After 24 hours, the coolers were opened again. The temperature of the ice and water mixture in the Yeti cooler remained at 33.1F. During the same period, the temperature of the ice and water mixture in the Coleman cooler rose to 48.2F. A qualitative visual analysis of the ice and water mixture in both coolers reveals no ice remaining in the Coleman cooler, while the Yeti cooler has retained a significant proportion of it's ice content.

August 30, 2017, 0600, 33.1F

August 30, 2017, 0600, 48.2F

After 36 hours, the coolers were opened again. The temperature of the ice and water mixture in the Yeti cooler rose to 33.4F. During the same period, the temperature of the water in the Coleman cooler rose to 66.2F. A qualitative visual analysis of the ice and water mixture in both coolers reveals no ice remaining in the Coleman cooler, while the Yeti cooler has retained a significant proportion of it's ice content.

August 30, 2017, 1800, 33.4F

August 30, 2017, 1800, 66.2F

After 48 hours, the coolers were opened again. The temperature of the ice and water mixture in the Yeti cooler rose to 33.5F. During the same period, the temperature of the water in the Coleman cooler rose to 66.4F. A qualitative visual analysis of the ice and water mixture in both coolers reveals no ice remaining in the Coleman cooler.  The Yeti cooler has some ice remaining, but most of it has melted.

August 31, 2017, 0600, 33.5F

August 31, 2017, 0600, 33.5F

Results

Under the controlled conditions of this experiment, the Yeti Cooler was able to maintain a consistent temperature of ice and water for 48 hours, while the Coleman Cooler was able to maintain a consistent temperature for 12 hours. 

There is a significant difference in the materials and lid design of the the two coolers. The Yeti cooler is a double walled stainless steel vacuum container, while the Coleman cooler is an insulated plastic design. There is also a significant difference in the size and design of the cooler tops, the Yeti cooler uses a heavy, thick, insulated material, while the Coleman cooler is a much thinner and uninsulated plastic. The lid design may play a role in the accelerated heat transfer of the Coleman cooler.

Yeti cooler lid vs. Coleman cooler lid.

Future Reasearch

Areas for additional study could include:

• Half gallon sizes of the respective coolers from each manufacturer (or others).
• Changing the ice to water ratio in each cooler to optimize drinkable water over a specified time period.
• Testing under different environmental conditions.