I recently bought a pressure activated gel cooling pad for my dog.
(comparable product: https://www.amazon.com/Hugs-Pet-Products-Pressure-Activated/dp/B00C65TXO6)
The mat is filled with a gel that noticeably cools down, when light pressure is applied. Now, in my understanding compression should lead to an increase in temperature.
Unfortunately I was not able to find any sources that explain the effect involved in pressure induced cooling of the gel inside the cooling pad. I could also not find any further information about the gel itself that is inside the cooling mat.
Can someone explain to me how such a cooling pad works and what the physics are behind it? I would also be happy if someone could point me towards any literature on this topic.