The Franklin stove is a metal-coated fireplace named after Benjamin Franklin, who discovered it in 1741. It has a hollow insulation near the back (to transfer more heat from the fire into the air of the room) and relies on the "inverted siphon" to pull the hot smoke of fire around the baffle. It was meant to produce more heat and less smoke than a regular open fireplace, but it did achieve a bit of sales until it was repaired by David Rittenhouse. It is also known as "circulation stove" or "Pennsylvania fireplace".
Video Franklin stove
History
The two features that distinguish Franklin's stove are hollow insulation (ie, metal panels that direct the flow of fire smoke) and a chimney that acts as an inverted siphon.
Baffle in fireplace
Baffles are used to extend a good lane of room air or smoke flames must flow through the required air ducts, thus allowing more heat to be transferred to indoor air or than smoke flames. In particular, channels can be installed on walls around the fireplace; cold room air will then enter the lower end of the channel, heated by the hot duct wall, up, and finally out of the top of the channel and back into the room. The longer the path the air passes, the more heat is transferred from fire to air. Likewise, the longer the channel through which the smoke of fire has to flow before it reaches the chimney, the more heat will be transferred from the smoke to the room air.
The use of baffles to extract more heat from fire and smoke is not new. In 1618, Franz Kessler (c. 1580-1650) from Frankfurt-am-Main, Germany published the Holzsparkunst (Wood Saving Art), featuring a stove where smoke from a fire was forced to snake through five spaces, one in over another, before entering the chimney. Kessler also documented a closed heater furnace which, like the Franklin stove, had a baffle just behind the fire, thereby extending the path through which smoke must fire before it reached the chimney.
In 1624, a French physician, Louis Savot (1579-1640), described the fireplace he had built in the Louvre. Channels pass under, behind, and over fire in fireplace. The cool air in the room enters the lower channel opening, warms, rises, and returns to the room through the channel's top openings. In 1713, the Frenchman Nicolas Gauger (ca. 1680-1730) published a book, La MÃÆ'Â © canique du Feu ... (Fire Mechanics), where he presented new designs for fireplaces. Gauger surrounded the fireplace with empty space. Inside these spaces there is a baffle. Cool room air enters the chambers through the bottom openings, warms as it sways around the baffles in the rooms, and returns to the room through the top openings.
At the Franklin stove, the hollow brace is positioned inside and near the back of the stove. The baffle is a wide but thin iron box, which opens into the air of the room at the bottom and in two holes on the sides, near the top. Air enters the bottom of the box and is heated both by fire and by the smoke flowing in the front and back of the box. The warm air then climbs into the baffle and out through the hole on the side of the baffle. Franklin baffles thus performing at least two functions: such as Kessler's heating stove, it's extended the way that fire smoke must follow before it reaches the chimney, allowing more heat to be extracted from the smoke; and like the Gauger fireplace, he puts a channel near the fire, which heats room air through convection.
Chiffon upside down in a fireplace
Some early researchers reasoned that if a fire in a fireplace is connected by a U-shaped channel to a chimney, the hot gas rising through the chimney will pull the smoke of fire and the first smoke down through one leg U and then up through the legs and other chimneys. This is what Franklin calls "air siphon" or "siphon revers'd". This inverted Siphon is used to pull the hot smoke of fire forward and to the bottom of Franklin's hollow stove, to extract as much heat from the smoke as possible.
The earliest known example of an inverted siphon is the 1618 fireplace of Franz Kessler. The fire burns in a ceramic box. Inside the box and behind the fire there is an insulation. Baffles force the smoke of fire down the back of the baffle before it goes out into the chimney. The goal is to extract as much heat from the smoke by extending the path that smoke must follow before reaching the chimney.
1678 Prince Rupert's fireplace (1619-1682) also includes an upside-down siphon. Rupert placed a metal door hanging between the bars of fire and the chimney. To get out through the chimney, the smoke and smoke of fire must first come down under the edge of the door before rising through the chimney.
Another early example of inverted siphon is the stove that was exhibited in 1686 at the annual Foire Saint-Germain, Paris. The inventor, AndrÃÆ' Dalesme (1643-1727), called it a smokeless stove ( furnus acapnos ). The stove consists of a bowl of iron in which fuel is burned. A pipe extends from the bottom of the bowl and then upwards into a chimney. Shortly after lit a fire inside the bowl, the hot air will begin to rise through the pipe and then up to the chimney; this creates the design down through the bowl, which draws the fire and its vapor into the bowl. After the draft begins, it stands alone as long as the fire is on. The Dalesme Stove can burn wood, incense, and even "coal in cat-pee" but produce very little smoke or odor. These results indicate that fire can be used indoors, without filling the house with smoke.
Franklin's stove contains an insulator just behind the fire, which forces the smoke of fire to flow down before they reach the chimney. It requires a U-shaped channel on the floor behind the stove, so smoke can flow from the stove to the chimney. So Franklin's stove puts the siphon upside down.
Franklin research and development
The Gauger book on its innovative fireplace design is translated into English - Fires Improv'd: Becoming a New Method of Building a Chimney, So Preventing Their Smoaking (1715) - by French immigrants to England, Jean ThÃÆ'Â © ophile Desaguliers (1683-1744 ). In a postscript to Desaguliers 'A Course in Experimental Philosophy' (1744), Desaguliers again briefly describes the Gauger fireplace and mentions his own work on the subject. Franklin read the two Desaguliers books and developed his own design for a stove that could provide more heat with less smoke.
In 1742, Franklin completed his first design that applied new scientific concepts of heat that had been developed by Dutch physician Herman Boerhaave (1668-1738), proponent of the idea of ​​Isaac Newton. Two years later, Franklin wrote a pamphlet describing his design and how it works to sell its products. Around this time, Pennsylvania's deputy governor George Thomas proposed to Franklin to patent his design, but Franklin never patented his design and inventions. He believes "that when we enjoy the great benefits of the discoveries of others, we must be pleased with the opportunity to serve others with our invention, and this we must do freely and generously." As a result, many others can use the Franklin design and fix it. Although the stove is intended for the dual purpose of cooking and heating the room, as time passes and the new furnace design becomes available, the main use of Franklin's stove becomes heating up the room. Many others improved Franklin's stove design, but to this day, most American fireplaces are box-shaped, similar to the Franklin stove. The exception is the Rumford fireplace, developed by Benjamin Thompson.
Maps Franklin stove
Stove design
The stove is about 30 inches (76 cm) high, with a box shape. The front is open, except for the decorative panel at the top of the box. The back of the box should be placed a few inches from the chimney (chimney). In the bottom panel there are several holes to allow smoke out; it is connected to the chimney. The panel is bolted together with an iron screw through the pre-printed ear. Inside is a thin, thin rectangular prism that will force the smoke into the hole. All the plates are made of iron.
Franklin stove sold poorly. The problem lies in the reverse siphon: smoke must pass through a cold funnel (which is installed on the floor) before the smoke can enter the chimney; consequently, the smoke cools too much and the stove does not have a good concept. Siphon upside down will operate properly only if the fire burns continuously, so the temperature in the funnel is high enough to produce the draft.
The newer version, designed by David Rittenhouse, solved many of the problems caused by Franklin's original stove, and became popular. Franklin's fame exceeds Rittenhouse, so history commemorates Franklin Stove rather than Rittenhouse Stove. The smaller Latrobe stove, often referred to as the Baltimore Heater, was patented in 1846 and became popular.
See also
References
Further reading
- Franklin, Benjamin, Description of the New Coal Burning Stove, and Consuming All the Smoke. American Philosophical Society Transactions. Vol. 2, (1786), p. 57-74. American Philosophical Society.
- Rogers, Jr. et al.. Franklin Stove. US. Patent 3,213,846 . October 26, 1965.
- Franklin, Benjamin. "Benjamin Franklin's Autobiography." Preliminary Archiving of America: The Main Source Materials of the 18th Century America. Web. November 14, 2010.
External links
- Franklin Stove in Lemelson-MIT Program
- The Franklin Stove on The Great Idea Finder
- Picture from Franklin Stove. University of Houston.
- Warwick Furnace, Chester County, PA First author of Franklin Stove - HMdb Marker
Source of the article : Wikipedia
0 Comments