摘要:
An energy harvesting system for converting thermal energy to mechanical energy includes a heat engine that operates using a shape memory alloy active material. The shape memory alloy member may be in thermal communication with a hot region at a first temperature and a cold region at a second temperature lower than the first temperature. The shape memory alloy material may be configured to selectively change crystallographic phase between martensite to austenite and thereby one of contract and expand in response to the first and second temperatures. A thermal conduction element may be in direct contact with the SMA material, where the thermal conduction element is configured to receive thermal energy from the hot region and to transfer a portion of the received thermal energy to the SMA material through conduction.
摘要:
An energy harvesting system for converting thermal energy to mechanical energy includes a heat engine that operates using a shape memory alloy active material. The shape memory alloy member may be in thermal communication with a hot region at a first temperature and a cold region at a second temperature lower than the first temperature. The shape memory alloy material may be configured to selectively change crystallographic phase between martensite to austenite and thereby one of contract and expand in response to the first and second temperatures. A thermal conduction element may be in direct contact with the SMA material, where the thermal conduction element is configured to receive thermal energy from the hot region and to transfer a portion of the received thermal energy to the SMA material through conduction.
摘要:
An energy harvesting system in thermal communication with a hot region and a cold region includes a hot end heat engine in thermal communication with the hot region, a cold end heat engine in thermal communication with the cold region, and an intermediate heat engine disposed between the hot end heat engine and the cold end heat engine. The hot end heat engine includes a hot end shape memory alloy (SMA) element, the cold end heat engine includes a cold end SMA element disposed, and the intermediate heat engine includes an intermediate SMA element. A hot side of the intermediate SMA element is in thermal communication with a cold side of the hot end SMA element. A cold side of the intermediate SMA element is in thermal communication with a hot side of the cold end SMA element.
摘要:
A device and method for controlling a phase transformation temperature of a shape memory alloy is provided. The device includes a primary wire composed of the shape memory alloy. The primary wire defines first and second ends, the first end being attached to a fixed structure and the second end being able to displace. An activation source is thermally coupled to the wire and is operable to selectively cause the primary wire to reversibly transform from a Martensitic phase to an Austenitic phase during a cycle. A loading element is operatively connected to the primary wire and configured to selectively increase a tensile load on the primary wire when an ambient temperature is at or above a threshold temperature, thereby increasing the phase transformation temperature of the primary wire.
摘要:
A device and method for controlling a phase transformation temperature of a shape memory alloy is provided. The device includes a primary wire composed of the shape memory alloy. The primary wire defines first and second ends, the first end being attached to a fixed structure and the second end being able to displace. An activation source is thermally coupled to the wire and is operable to selectively cause the primary wire to reversibly transform from a Martensitic phase to an Austenitic phase during a cycle. A loading element is operatively connected to the primary wire and configured to selectively increase a tensile load on the primary wire when an ambient temperature is at or above a threshold temperature, thereby increasing the phase transformation temperature of the primary wire.
摘要:
A process for upgrading bitumen recovered from an oil reservoir without hydrogen production is particularly useful in field upgrading applications. In this process, recovered bitumen enters a fractionator and is contacted with heated gases from a fluidized bed reactor. The bitumen and heated gases are fractionated into segregated products including at least a liquid pitch, unstable fractions, and an upgraded liquid product. The liquid pitch is introduced into the reactor to produce a vapor phase liquid product; the reactor comprises solid particles moving through the reactor and a fluidizing gas fluidizing the solid particles at a conversion temperature which is suitable for facilitating the conversion of at least some of the liquid pitch into the vapor phase liquid product. The heated gases comprising the vapor phase liquid product and fluidizing gas are directed from the reactor to the fractionator to contact the bitumen stream. In this process, enough of the segregated unstable fractions are burned that the liquid product and any remaining unstable fractions meets pipeline specifications without hydrogen treatment of any of the remaining unstable fractions.
摘要:
An irrigation valve box includes a body for shielding the valve, which forms an opening at the top, and a removable lid for fitting into the opening formed by the body. Access to the valve is normally gained by removing the lid. Metal is associated with the valve box for the purpose of being detected by a metal detector. In one arrangement the metal forms a plate which fits into the removable lid. In an arrangement especially suited for a larger or commercial valve box, the metal forms a metal ring which fits into the removable lid. In yet another arrangement, the lid comprises molded plastic or molded rubber and the metal is molded into the lid. In one such an arrangement, the metal forms a wire mesh. A method for detecting an irrigation valve box which is hidden from view by soil or grass, includes the combination steps of associating metal with the valve box at an earlier time when the location of the valve box was known, so that the metal is detectable by a metal detector, and using a metal detector to locate the metal, and thereby to locate the valve box. One arrangement of the method includes the steps of forming the metal into a plate and fitting the metal plate into the removable lid. Another arrangement of the method includes the steps of forming the metal into a metal ring and fitting the metal ring into the removable lid. Yet another arrangement of the method includes the step of forming the metal into the removable lid, such as forming the metal into a mesh molded into the removable lid.
摘要:
A liquid feed material such as a heavy hydrocarbon feed in liquid form is contacted with a fluidized bed of heated solid particles which have a bulk horizontal velocity which is generally perpendicular to the flow of a fluidizing medium. The liquid feed material reacts on the solid particles to produce a vapor phase product, which vapor phase product is collected in a vapor collection apparatus.
摘要:
A durum wheat-based ingredient, preferably durum wheat flour, is used in the production of chip-like snacks having a very crunchy, fracturable, non-mealy texture. A machinable dough is formed from at least one durum wheat ingredient, such as durum flour, a no-gluten or low-gluten content starchy material, such as dehydrated potato flakes, water, and a reducing agent, such as sodium metabisulfite. The amount of the durum wheat ingredient may be from about 45% by weight to about 75% by weight, and the amount of reducing agent may be from about 50 ppm to about 300 ppm, based upon the total weight of the durum wheat ingredient and no-gluten or low-gluten content starchy material used to form the machinable dough. The dough may be sheeted, cut into pieces, and baked to a moisture content of less than about 4% by weight. The doughs may be used to produce reduced-fat, low-fat, or zero-fat chip-like products which provide a snapping or cracking sound upon breaking. The reducing agent promotes machinability and a crunchy, non-mealy chip-like texture in the snack.
摘要:
A fluidized bed coking reactor apparatus comprises a reaction vessel; a temperature sensor inside the reaction vessel for measuring a reactor temperature, a solids feed mechanism for feeding solid particles into the reactor vessel at a mass flow rate, a feed material feed mechanism for feeding feed material into the reactor at an operating feed rate; and a supervisory controller programmed to determine an upper feed material feed rate of the reactor when operating at the reactor temperature and receiving solid particles at the mass flow rate. The upper feed material feed rate is defined as a feed rate of feed material deposited onto a selected fraction of a fluidized bed of solid particles that causes defluidization in the reactor when the reactor is operating under conditions having a selected degree of backmixing in the fluidized bed, wherein the degree of backmixing is modeled as a selected number of reactors arranged in series and each operating under continuous well-mixed conditions, with the selected number of reactors being an integer between one and infinity.