How the SunWorks™ Dryer Works
The Z-Flow Concept
The Sunworks™ Solar Food Dryer uses a unique "Z-Flow" airflow pattern to greatly improve performance and drying speed. This airflow is powered by the buoyancy of warm air in the dryer, referred to as natural convection or the solar fan.
Here's how it works...
Step 1: Sunshine creates warm air inside the dryer (Figure 1) that wants to rise up and out the vents at the top. This exiting air must be replaced by cooler, fresh air entering at the bottom inlet vent.
Step 2: Cool, fresh air is preheated as it enters at the bottom of the dryer and passes under the absorber heating plate (Figure 2). This assures that the air is warmed before it reaches the food. It also utilizes all the heat from the bottom of the absorber plate, improving efficiency and eliminating the need for insulation on the bottom.
Step 3: The pre-warmed air passes back across the trays of food while being further heated by the sun. This achieves even drying of the food and gets the most drying out of the heated air before it is exhausted from the upper vents.
The result is fast, even drying and maximum efficiency. The adjustable rear vent allows control of drying temperature. Round side vents assure minimum venting at all times to prevent overheating.
Advantages of Direct + Indirect Solar Heating
The SunWorks™ dryer uses both direct and indirect solar heating for faster drying. To understand why this is important, consider this scenario: You have two identical damp towels and place one in the sun and one in the shade. Which will dry fastest? Both locations have the same air temperature and same breeze (indirect solar). But you probably know from experience that the towel in the sunny location will dry much faster. This is because, in addition to the breeze and warm air in the shady location, the towel in the sunny location gets direct heating from the sun. It works the same for food in a solar dryer. Not only does it dry faster, but food gets dryer, so it lasts longer.
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