"spread heat" is a correct and usable phrase in written English.
You can use it when you want to describe something that is radiating warmth, or is figuratively "spreading" warmth. For example: "The fire spread heat throughout the room, creating a cozy atmosphere."
The most common solution is to use conductive metal fins to spread heat through the device.
At low Reynolds number, the fluid mean velocity is low and the fluid has more time to absorb and spread heat; therefore, diffusive heat transfer is the dominant player, causing the fluid to obtain a lower bulk temperature.
This is because with increasing internal Reynolds number, the fluid mean velocity increases and the fluid does not have enough time to spread heat; therefore, the effectiveness decreases and the outlet temperature increases.
The four designs are compared based on their ability to spread heat evenly and rapidly into the phase change material (PCM) and the ease with which heat can be withdrawn from the device for cooking.
The shape itself is designed to spread heat evenly.
Big, inexpensive, thin pot bottoms don't spread heat well and tend to scorch a little spot.
Here and here are links to more detail from the Hansen study, with some fascinating visualizations of the spreading heat.
Also, when compared to copper, GE's substrate is a quarter the weight, spreads heat twice as fast, and can operate at 10x the force of gravity.
While heat pipes are a widely used and highly efficient means of spreading heat or transferring it from one location to another, there are some fluid-casing combinations which cannot be used due to material incompatibilities.
While no consumers typically eat the spread heated at that temperature, some companies do cook palm oil at high temperatures to burn off its natural red coloring and to neutralize its odor.
Note that you should not try to calm the heat of a pepper by gulping water since water will only spread the heat around your mouth.
