Alternate fuel storage system and method
A fuel tank for storing an alternate fuel and providing the fuel to an internal combustion engine includes: an inner shell with an internal cavity designed to store fuel; an outer shell configured and positioned relative to the inner shell such that an interstitial volume is created between the inner and outer shells; and a heating unit positioned in the interstitial volume. In some embodiments, the interstitial volume is filled with air; in other embodiments, the interstitial volume is filled with a thermally insulative material.
1. A fuel tank for storing fuel containing an alternate fuel for delivery to an internal combustion engine, the fuel tank comprising:
an inner shell with an internal cavity configured to store fuel containing an alternate fuel;
an outer shell configured and positioned relative to the inner shell such that an interstitial space is created closed between the inner shell and the outer shell; and
a heating unit positioned in the interstitial space, the heating unit configured to transfer heat energy to the fuel stored within the inner shell.
2. The fuel tank of claim 1 , wherein the fuel is comprised of at least one of biodiesel fuel and vegetable oil.
3. The fuel tank of claim 1 , wherein the fuel also contains diesel fuel.
4. The fuel tank defined in claim 1 , wherein the interstitial space is filled with a gas.
5. The fuel tank defined in claim 1 , wherein the interstitial space is filled with at least one thermally insulative material.
6. The fuel tank defined in claim 1 , wherein the interstitial space is evacuated.
7. The fuel tank defined in claim 1 , wherein the heating unit is a heat exchanger.
8. The fuel tank defined in claim 1 , wherein the heating unit is mounted on an outer surface of the inner shell.
9. The fuel tank defined in claim 1 , wherein the heating unit includes a control device that prevents coolant from reaching a portion of the heat exchanger.
10. The fuel tank defined in claim 9 , wherein the control device is operatively associated with a temperature sensor positioned to detect the temperature of coolant in circulation.
11. The fuel tank defined in claim 9 , further comprising a temperature sensor positioned to detect the temperature of fuel in the inner shell, the temperature sensor being operatively associated with the control device.
12. The fuel tank of claim 11 , wherein the control device is configured to control the heating unit based on the temperature of the fuel in the inner shell.
13. The fuel tank defined in claim 1 , further comprising a temperature sensor positioned to detect the temperature of fuel in the inner shell.
14. The fuel tank of claim 13 , wherein the control device is configured to control disable heating unit from heating the fuel in the inner shell when the temperature of the fuel in the inner shell exceeds a temperature threshold.
15. The fuel tank defined in claim 1 , wherein the heating unit comprises an electrical heating element.
16. The fuel tank defined in claim 15 , wherein the heating element is configured to be connected to power through electrical conductors that extend outside the outer shell.
17. The fuel tank defined in claim 15 , further comprising a thermostat operatively associated with the heating element.
18. The fuel tank defined in claim 1 , wherein the inner shell is thermally conductive.
19. The fuel tank defined in claim 1 , further comprising a fuel volume sensor configured to provide a representation of the volume of the fuel stored in the inner shell.
20. The fuel tank defined in claim 1 , further comprising a fuel viscosity sensor configured to provide a representation of the viscosity of the fuel stored in the inner shell.
21. The fuel tank of claim 1 , wherein the heating unit, inner shell and outer shell are mounted on a common mounting structure.