FIELD OF THE INVENTION:

This invention relates to the field of thermal engineering, optical engineering, and electromagnetic engineering.

Particularly, this invention relates to a jacketed heat-retaining vessel. BACKGROUND OF THE INVENTION:

The world is facing a huge crisis. Most of the energy we use today and take for granted, is obtained from fossil fuels, directly or indirectly. The world now consumes 97 million barrels of oil per day (1 barrel is approximately 160 litres), or 180,000 litres per second, and the demand is growing rapidly.

People are waking up to the realization that the days of cheap oil based energy are over.

Peak oil is a reality that we see around us today (demand surpassing production capacity). Oil companies are trying to dig deeper into the ocean (with exponential rise in cost, as a function of depth of exploration) to find oil. They are not doing this for fun, but the reality is that cheap oil sources have dwindled. What happened in the Gulf of Mexico a few years ago is an example of human- inflicted catastrophes from oil-rig disasters. These are still fresh in our memory.

Other sources of energy, such as nuclear energy has its own perils, as is evidenced from the number of nuclear plant disasters that happened in recent history (Chernobyl, Three Mile Island, Fukushima, etc., being the poster candidates highlighting the perils involved with nuclear energy). The bottom line is that the world at large still does not know how to deal with nuclear energy safely, including storing or disposing off of the spent nuclear fuel, which would continue to be radioactive for thousands of years.

The emergence of thinking on safer, and renewable sources of energy is therefore not by accident. People are exploring solar PV, solar thermal, wind, tidal, geothermal, etc, as other viable sources of renewable energy. However, one thing is clear. Whatever be the source for the renewable energy, we cannot afford to squander what we are generating.

Energy is precious. Energy is the true currency for wealth.

The world is in dire need for energy efficient solutions. Almost every aspect of our modern existence is dependent on energy. Most of the energy we use today is still derived from fossil fuel sources. Thus energy efficient products and solutions are among the most important things to consider in our times ahead.

Even for our basic survival needs, say for cooking, we use energy. In developing and underdeveloped countries and societies, the energy requirement for cooking is very significant fraction of the total energy needs. In India for example, the middle class is still largely dependent on LPG and kerosene for cooking. An average household of four consumes one cylinder a month or 12 cylinders in a year or 170 kg of LPG. Government of India spends nearly Rs.20,000-40,000 crores annually (or approximately US$3-6 billion) on LPG subsidies alone. Similar figures appear for kerosene as well. The actual cost (beyond subsidies) is a factor of 2-3 times larger as compared to the subsidies. Thus this is a very large problem, and any significant solution in this regard would be a game changer. There are many studies and projects that have attempted to create "energy efficient stoves". In the African context, women are primarily responsible for gathering firewood, and they need to go far. This makes them vulnerable and crimes like rape, abduction and assault are common. According to some studies done in Berkeley, three billion people cook meals over open fires each day creating pollution that kills 4.3 million people each year. The biomass (wood, animal dung and crop residue) used as fuel gives off toxic smoke at about seven times the safe limit set by the U.S. Environmental Protection Agency, (EPA). Studies also indicate that wood used as a cooking fuel results in nearly half of worlds' deforestation. The very process of gathering and carrying firewood for long distances, itself results in medical problems such as severe neck and back injuries.

Another approach to solve the problem of energy needs for cooking has been attempted with a variety of solar cookers. These come in various forms. From box-type, with glass top, panel-type with several reflecting panels directing heat to the cooking zone, or even parabolic reflector based stoves or steam generating methods, there are have been many independent attempts to solve the problem of cooking by using the energy from the Sun directly.

However, in spite of these laudable attempts to solve a major problem, most of these solutions are primarily implementations of energy efficient wood burning stoves, whose primary users are rural communities. As noted above, firewood based cooking has its own set of problems. An even more important question is how to address cooking energy needs of the increasing urban (or urbanized) population around the globe.

The cooking stove's energy efficiency has been the focus of a fair number of scientists, but then it is only a part of the energy efficiency equation. Comparatively much less work appears to address energy efficiency aspects of the cooking pot itself. Traditionally, the pressure cooker has been projected as an energy efficient device. But even in this case, an open gas flame tends to deliver only about 20% of the combustion energy to the pot, including a pressure cooker. Flat bottomed cookware allows for more contact with heating elements, which in turn more effectively heats your pan. A warped-bottom pot could take 50% more energy to boil water than its flat bottomed counterparts. Relatively fewer research interests have directed attention to the cooking pot itself. Slow-cooking aids such as Wonderbags are also helpful.

Overall, there is a significant void in this sector. The vast energy wastage from our daily cooking itself can be arrested immediately.

In all traditional cooking methods, there is heat (energy) loss from the cooking process itself. Any object raised to a higher temperature would lose heat by the processes of conduction, convection and radiation. Other processes, such as phase-changes, say water escaping as steam, would also lead to losses. Heat is also sometimes lost due to mass transfer, say when we drain off water from boiled rice, discarding it.

Additionally the efficiency of energy transfer from the heating source (stove or oven for example) to the cooking container is often inefficient. For example, in the case of a pot on a gas stove, only about 20% of the energy of combustion from the burning gas gets transferred to the pot.

There are many other indirect energy costs associated with any fuel source too. For example, a cylinder of gas needs to be physically brought in to a user, and this would happen by transporting them on trucks from the filling stations to the distributors and then to the homes. Careful analysis reveals that great amount of energy is lost in standard cooking processes.

Much of cooking appears to use the following basic processes, in different temperature ranges:

• Boiling: This includes boiling, steaming, stewing, blanching, etc. This involves cooking ingredients in watery medium. Thus the temperature of the cooking process occurs around 100 degrees Celsius.

• Thermal Cooking: Cooking at temperatures in 80-100 degrees Celsius. This is also called slow cooking, and is important for many different types of food (rice, lentils/pulses, soups, etc).

• Frying: This includes deep frying, pan-frying, saute, etc. The temperature of frying is typically around 170-200 degree Celsius.

• Baking: Oven air temperature should be around 170-235 degree Celsius for different kinds of baked foods (breads, biscuits, cakes, etc).

OBJECTS OF THE INVENTION:

An object of the invention is to reduce consumption of energy required during a heating process.

Another object of the invention is to reduce cost involved in the heating process of a vessel or a utensil.

Yet another object of the invention is to prevent heat loss during heating process of a vessel or a utensil. Still another object of the invention is to preserve heat loss during heating process of a vessel or a utensil and use this preserved loss to accelerate heating process.

Another object of the invention is to achieve clean-energy heating, thereby reducing indirect medical and social implications associated in the heating process.

SUMMARY OF THE INVENTION:

According to this invention, there is provided a jacketed heat-retaining vessel comprising:

- a pre-designed heat-retention jacket configured to envelope a vessel, characterised in that, said heat-retention jacket comprising embedded heat delivery mechanisms in order to provide heat to said enveloped vessel; and

- said jacket comprises at least one layer of insulating material and at least one layer of radiation reflective material alternatively interspersed along a radially outward direction from the vessel centre.

Typically, said jacket comprises a plurality of sheets of radiation reflective material in concentric configuration with respect to said vessel.

Typically, said jacket comprises a plurality of sheets of radiation reflective material in a spiral configuration with respect to said vessel.

Typically, said radiation reflecting layer is formed in a continuous series of loops in a layered forms about a cylindrical axis of said vessel.

Typically, said radiation reflecting layer is formed in a non-continuous series of loops in a layered forms about a cylindrical axis of said vessel. In at least one embodiment, said insulating layer is formed in a continuous series of loops in a layered form about a cylindrical axis of said vessel.

In at least one embodiment, said insulating layer is formed in a non-continuous series of loops in a layered form about a cylindrical axis of said vessel.

In at least one embodiment, said jacket is a passive heat-retaining jacket.

In at least one embodiment, said jacket comprises multiple layers of insulating material with radiation reflective layers interspersed between said insulating materials.

In at least one embodiment, said jacket comprises at least one layer of insulating material and at least one layer of radiation reflective material, characterised in that, said radiation reflective layer is any reflective layer.

In at least one embodiment, said vessel comprising a bottom shield for said predesigned heat-retention jacket which covers said embedded induction coils.

In at least one embodiment, said vessel comprising a bottom shield for said predesigned heat-retention jacket which covers an energy source configured to deliver heat.

In at least one embodiment, said vessel comprising a top thermal shield. In at least one embodiment, said vessel comprises a side thermal shield. Typically, said vessel comprises a box comprising a connector attaching to said jacket, said connector carrying sensing probes to allow accurate control of energy injection process, thereby increasing efficiencies and the convenience of operation.

In at least one embodiment, said jacket is a solar thermal pre-designed heat retention jacket.

In at least one embodiment, said jacket is a vacuum thermal pre-designed heat retention jacket.

In at least one embodiment, said jacket is a mylar sheet jacket.

Typically, said jacket comprises sensing mechanisms selected from a group of mechanisms consisting of thermocouple temperature sensing mechanisms, infrared sensors, pressure sensors, resistance sensors.

Typically, said vessel is communicably coupled to at least a heat delivery mechanism, said heat delivery mechanism being selected from a group of mechanisms consisting of a conductive heat delivery mechanism, a convective heat delivery mechanism, a radiative heat delivery mechanism, and a generative heat delivery mechanism.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:

The invention will now be described in relation to the accompanying drawings, in which:

Figure 1 illustrates a vessel inside pre-designed jacket(s); Figure 2 illustrates a vessel with external heating; and Figure 3 illustrates a vessel with internal heating.

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS:

According to this invention, there is provided a jacketed heat-retaining vessel.

This is achieved by trying to plug all the loss channels, viz, through conduction, convection, radiation, phase-change and mass-transfer. In addition, this invention tries to ensure maximization of efficiency for heat generation and transfer to the cooking zone and medium or to a reaction zone where this invention is placed.

In accordance with an embodiment of this invention, there is provided a predesigned heat-retention jacket configured to ensconce / envelope a utensil. Typically, this is a passive heat-retaining jacket. The retention of heat within the jacket allows contents, in the vessel ensconced / enveloped within the jacket, to be continuously cooked even when it is not in communication with a direct source of heat. According to an exemplary embodiment, the vessel could be heated by any of the conventional means and then inserted into this predesigned jacket as soon as the contents reach boiling temperatures. Its vessel specific pre-designed configuration makes heat retention relatively higher.

Typically, the jacket comprises at least one layer of insulating material and at least one layer of radiation preventing material.

Preferably, the jacket comprises multiple layers of insulating material with radiation prevention layers interspersed between the insulating materials. This radiation preventive layer is any reflective layer.

Heat loss due to conduction is stopped due to the insulating layer.

Heat loss due to convection is stopped due to close jacketing around the vessel.

Heat loss due to radiation is stopped due to the radiation prevention / reflective layer.

Heat loss due to mass transfer is prevented from escaping steam (which would otherwise carry away valuable energy out of the system), by ensuring steam is not generated or barely generated in the first place.

For most cooking processes, which have residual water (at the end of heating), such as boiling rice, pulses, stewing vegetables, or the like, the temperature of the vessel never goes much above 100 degrees Celsius. Under these cooking conditions a standard induction stove and a vessel of this invention may be used. In some other embodiments, other mechanisms of energy delivery can be used e.g. by hot fluids circulating in coils optical radiation, hot gases, steam, and the like.

This will allow added benefit of not having to touch any hot exposed metal part of the vessel. The heat-retaining jacket is kept all along, saving more energy, even during the heating-up process.

The jacket does not experience temperatures in excess of 100 degrees Celsius and therefore efficient material choices in the manufacture of the jacket can be exploited. (100 degrees Celsius maximum is only for boiling; as stated before other processes, such as frying, baking, and the like require higher temperature)

Figure 1 illustrates a vessel inside pre-designed jacket(s). Reference numeral 1 refers to a Vessel / Pot

Reference numeral 2 refers to a Lid / Cover

Reference numeral 3 refers to a Side thermal shield of the pre-designed jacket. Reference numeral 4 refers to a Top thermal shield of the pre-designed jacket. Reference numeral 5 refers to a Bottom thermal shield of the pre-designed jacket.

Although open flames may not be the best process to transfer energy to the vessel and ingredients, this is currently a widely accepted process around the world.

In accordance with another embodiment of this invention, there is provided a vessel which is resistant to direct flames. Careful choice of materials ensures not only fire resistance, but also non-toxic and food-friendly materials and processes.

Figure 2 illustrates a vessel with external heating.

Reference numeral 1 refers to a Vessel / Pot

Reference numeral 2 refers to a Lid / Cover

Reference numeral 3 refers to a Side thermal shield

Reference numeral 4 refers to a Top thermal shield

Reference numeral 5 refers to an External heating source

Reference numeral 6 refers to a Heated matter

Standard induction stove based heating still has problems of losses through the lower surface of the vessel (which is in close proximity to the induction coils of the stove). All other surfaces will have the heat-retention shields of the predesigned jacket. Also, there is inefficiency of energy conversion with a standard induction stove to the vessel for cooking. There are losses in the coils as well as the electronics driver circuits.

In accordance with yet another embodiment of this invention, there is provided a bottom shield for the pre-designed heat-retention jacket which covers the stove or heat source as well.

In at least one other embodiment, the pre-designed heat retention jacket comprises embedded induction coils in order to provide heat to the ensconced / / enveloped vessel.

The induction heating drivers are very energy efficient, and there are minimal losses for the process of radio-frequency generation to effect induction heating.

A separate box would have a connector attaching to the jacket. This connector could also carry temperature sensing probes to allow accurate control of energy injection process, thereby increasing efficiencies and the convenience of operation even more. Further, the connector could also carry pressure sensing probes to allow control based on changes in pressure.

Since the process of internal induction heating is more energy efficient, it can be used with energy obtained from Solar PV panels. A few solar PV panels, possibly put up as window shades on walls of apartment buildings that receive 3-4 hours of sunlight, along with battery storage, could allow a normal family's cooking energy needs for the full day and night be adequately satisfied.

In this form of solar cooking, one does not need to go out in the sun in the traditional and common description of solar cooking. Even people who stay in apartments in high-rises, or in congested slums, who do not have good access to open areas to put traditional solar cookers, could use the Solar PV along with this invention to good advantage.

The left over energy in the battery could easily be used for lighting or other small applications, say running one's laptop. In any case, when there is no sunlight (say during Monsoons and overcast days), the electronics could be run with standard household power as well. Thermal storage mechanisms, particularly for larger systems, could also cope with periods of no sunlight, say during certain monsoon days.

A modified version of the solar panel, which can be used to also heat water will come in as an even better version. Normal solar PV panels are around 12-15% efficient. This means that nearly 80+ of incident energy is wasted as heat in the panel (they can get very hot). If instead, normal solar panels are modified to also act as a hot surface and heat water or oil, and store it in insulated tanks for later use, then we can make even more energy efficient vessel of this invention. This hot water (or oil which could in turn heat water) will ensure that we can start the cooking process, say boiling, with water not at 25-30 degree Celsius, but say at 60-70 degrees Celsius. This way the solar PV energy needs to only boost the temperature by around 30 degrees Celsius, as opposed to from room temperature. This will likely more than halve the input energy requirement, resulting in the need for smaller battery and solar panel. Hence, lowering the cost on this front. The added complexity of a heat exchanger and a tank to store hot fluid, and a slight modification of the cooking process itself needs to be accommodated.

Figure 3 illustrates a vessel with internal heating Reference numeral 1 refers to a Vessel / Pot

Reference numeral 2 refers to a Lid / Cover

Reference numeral 3 refers to a Side thermal shield

Reference numeral 4 refers to a Top thermal shield

Reference numeral 5 refers to a Bottom thermal shield

Reference numeral 6 refers to an Internal heating source

Reference numeral 7 refers to a Heated matter

In accordance with still another embodiment of this invention, there is provided a solar thermal pre-designed heat retention jacket.

Normal household solar hot-water panels would heat water to around 60 to 80 degrees Celsius. With water as the thermic fluid, one cannot exceed 100 degrees, since water would change to steam. However, if one used other thermic fluids, say certain oils, then temperatures in the range of 150-170 degrees or higher is possible. Of course with larger scale, industrial solar heating systems, this would not be an issue. If heat could be injected directly inside the heat- retaining jackets, then all types of cooking can be done with solar thermal power alone. In at least one embodiment, maximum temperatures achieved is close to 300 degrees Celsius.

In accordance with still another embodiment of this invention, there is provided a vacuum thermal pre-designed heat retention jacket.

Certain cooking processes involve thickening of food by removal of water. One example traditionally, to create basundi or rabdi (condensed milk) is to heat and boil off the water. A better process may be to allow the "boiling" to happen at lower temperatures, by reducing the atmospheric pressure, or creating partial vacuum. Water would evaporate at lower temperature, thickening the milk for example.

If this process is carried out in a using the vessel of this invention, the process of evaporation would also cool the liquid. This may be an added bonus, to keep things refrigerated. Often such milk products need to be chilled to help preservation.

In at least one embodiment, the heat retaining jackets can be made of mylar sheets.

There are several salient advantages of this invention, which manifest in its various implementations:

1. Lower energy cost: Even if one conservatively estimates that half of conventional energy usage could be saved. This would amount to at least s.300-500 per month of saving for an average household. The cost of owning an energy efficient pot could therefore be recovered in a matter of months. Any additional savings is a saving for the individuals using it, it terms of fuel cost. Society at large benefits too, in terms of reduced fossil fuel usage.

2. Hot-pack property: If food cooked may be kept hot or warm for a long time, it can be a definite advantage. Not only does it save re -heating time and energy, but also allows one to make food less number of times, say at homes, restaurants, etc. If say rice is cooked and can be served hot even hours later, then it saves the trouble of having to cook rice on the fly, or make assumptions about consumption patterns in a restaurant for example.

3. Remote location usage: The lower energy requirement to cook food, can potentially allow one to cook food with relatively meagre sources of energy, perhaps even obtained from alternate energy sources. Traditionally, cooking using alternate energy was considered inadequate and therefore difficult. The ability to have very modest inputs of energy and still be able to cook food adequately, would allow one to cook practically anywhere, and not be tied up with conventional fuels and their consumption quantum.

4. Retro fitting: Potentially, this invention can be adapted to already existing pots, satisfying certain geometric constraints. In principle one could take one's favourite pots and make it compatible with this invention.

5. Cleaning / Hygiene: This invention will be designed to make them inherently easier to clean, thereby maintaining the standards of hygiene demanded in a cooking environment and equipment.

Although, this invention is described in relation to cooking utensils, it is to be understood that it is not just for cooking, but can be used as an efficient energy retaining container (say a tank of hot fluid). By the same token, the vessel can be treated as a heat efficient shield (say, for making better refrigerators or ice boxes or the like). This invention can be uses in similar processes such as in agro-processing, chemical industries, or the like.

While this detailed description has disclosed certain specific embodiments for illustrative purposes, various modifications will be apparent to those skilled in the art which do not constitute departures from the spirit and scope of the invention as defined in the following claims, and it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.