Space Fryer
Our story:
The proposed product is a prototype deep fat fryer (a.k.a Space Fryer) that achieves the intensification of the frying process by increasing the heat transfer rates from hot oil to the food. This is managed by altering the food orientation during frying and at the same time by exposing the food to increased gravitational forces (i.e. up to 0.5 ± 3.0 gearth). As a result Space Fryer prepares the food by consuming less energy (50%) in less time (60%), compared to the ordinary fryers. Shorter frying time, means that the oil will suffer less thermal stress during one single frying batch and therefore it may be re-used more times.
Target group or … commercialization feasibility of the product
The target group of the product includes domestic users, fast food services and food industry. The fact that Space-Fryer is the only fryer capable to produce fried food in microgravity conditions met in space missions, constitutes an advertisement asset. A preliminary cost breakdown analysis has shown that after using Space-Fryer for the six months, the sum of purchasing and operational costs will be less than the conventional fryers.
Progress of the project
Space Fryer incorporates the above knowledge, and its conceptual design is based on a planetary rotating system that rotates a rotating disk clockwise around its center. At the same time, a frying bowl (where the frying is actually taking place) is placed eccentrically on the rotating disk and spins around its own center. The combining rotation speed is arranged in such a way that the centrifugal and the Coriolis force promote a gravity acceleration enhancement up to 0.5 ± 3.0g earth. At the same time the continuously altering acceleration vector imposed on each one of the potatoes (inside the frying bowl) results to a continuous altering of the potatoes orientation. Both the effects of the increased magnitude of acceleration and the varying orientation are expected to increase more than 50% the heat transfer rates and to contribute to a 60% shorter frying time compared to conventional frying. Such sort frying time leads to less consumption of energy, despite the extra energy required to achieve the rotary motion and makes possible the oil reuse for more times than the regular frying.
Working principle
Space Fryer conceptual design is based on a planetary rotating system that rotates a rotating disk clockwise around its center. At the same time, a frying bowl (where the frying is actually taking place) is placed eccentrically on the rotating disk and spins around its own center. The combining rotation speed is arranged in such a way that the centrifugal and the Coriolis force promote a gravity acceleration enhancement up to 0.5 ± 3.0g earth. At the same time the continuously altering acceleration vector imposed on each one of the potatoes (inside the frying bowl) results to a continuous altering of the potatoes orientation. Both the effects of the increased magnitude of acceleration and the varying orientation are expected to increase more than 50% the heat transfer rates and to contribute to a 60% shorter frying time compared to conventional frying. Such sort frying time leads to less consumption of energy, despite the extra energy required to achieve the rotary motion and makes possible the oil reuse for more times than the regular frying.
Blue and red rotating arrows designate the clockwise and the counter current rotation of the disk and the bowl respectively. The red, black and light blue arrows stand for the centrifugal and Coriolis forces act inside the rotating bowl.
Our product
After been studying frying under the umbrella of European Space Agency (ESA) the last seven years, we were able to elucidate how frying process is affected by food orientation and gravity in two ways:
- First we found that a vertical surface exhibits much faster temperature rise (higher heat transfer rates) and more intense boiling phenomena than the horizontal surfaces. Crispier food is produced and less energy is consumed when the food is placed at a non-horizontal position inside the fryer.
- Secondly, we proved that altered levels of gravity acceleration leads to more than 50% increased heat and mass transfer to/from the food items. This has been attributed2 to the progressive enhancement of bubbles detachment from the potato surface up to 3.0g earth.
These specific design parameter is reached by building a prototype which incorporates mild rotary motion of planetary type while the food is being frying. As a result the frying food items are exposed to varying orientation and non-stationary increased magnitude of acceleration (up to 3.0 gearth).