This is what the science community has to say.
As temperature goes up, the molecules increase in thermal agitation manifested in linear motion and vibration. Regions that contain higher kinetic energy transfer the energy to regions with lower kinetic energy. Simply put, heat transfer can be grouped into three broad categories: conduction, convection, and radiation.
The main difference between herbal pens and portable vaporizers is the way in which they heat your material. Pen-style units utilize a method called conduction by transferring heat directly from the heating coil to your material. As a result of making direct contact with the heat source you get something happening called combustion and smoke is produced.
An easy way to understand how conduction works is by simply picturing a cup of tea. When hot tea is poured into a mug, heat is transferred directly from the hot tea to the coffee cup, thus heating the mug and causing it to be warm to the touch. The mug is what is called“conducting” the heat directly from the hot liquid itself.
In contrast, portable and handheld vaporizers employ a method called convection, which heats the material placed in a chamber by passing and circulating heated air through them. During this method, the herbal material being heated never comes into direct contact with the heating element, but is instead essentially “cooked” by the flowing airflow.
The simplest way to understand the principles of convection is to picture a hair dryer that you might have in your home. The heating element inside of the hair dryer heats the air which passes by it, which is then blown out and transferred from the hot air to your hair, which in turn warms and dries it. At no point does your hair ever come into direct contact with the heat source.
We will offer future articles on how this effects vaporizers in various categories being Home Use, Portables and Pen Wax and Oil Vaporizers.