105 results about "Natural convection flow" patented technology

Provided is a natural convection-driven polymerase chain reaction (PCR) apparatus and method, which can periodically change temperature of a sample to make a natural convection-driven flow in a loop-shaped channel on a disposable polymer chip and contacting heating metal members maintained at different temperatures with channels. The natural convection-driven PCR apparatus includes: a polymer chip having a plurality of channels connected together to form a loop-shaped microchannel, a sample being filled inside the channels; a plurality of heating metal members contacting the loop-shaped microchannel of the polymer chip and transferring heat; a temperature controller connected to the heating metal members to maintain the heating metal members at different temperatures; a plurality of heaters connected to the heating metal members and the temperature controller to supply heat to the heating metal members; and temperature sensors connected to the heating metal members and the temperature controller.

A heater assembly with enhanced cooling pursuant to various embodiments described herein makes use of fluidic flow in the insulation or in the space used for insulation. By creating a natural convection or forced convection flow, the heater cools down faster, it can operate at lower temperatures and / or higher temperature precision, and it can improve temperature controllability by generating higher heat loss rates.

An electronics module designed to efficiently remove heat from enclosed circuit boards via one or more configurable heat conduits. Each heat conduit is custom-configured to provide good thermal contact between the corresponding heat-generating electronic device of an enclosed circuit board and the clamshell housing that encloses the circuit board. Good thermal contact between the clamshell housing and the outer case of the electronic module facilitates efficient heat transfer to the finned exterior surface of the outer case, where the heat is dissipated into the ambient environment via thermal conduction, natural convection, forced convection, and / or thermal radiation. Depending on the topology of the circuit board and the individual characteristics of the electronic device to be cooled, the corresponding configurable heat conduit might be based on a nested heat-sink coupler, a fitted movable plug, or a flexible ribbon-shaped heat pipe.

The present invention provides a solid-state lighting fixture and lamp for down light for use in applications especially in recessed lighting. In particular, the lamp of the subject invention may be configured as a direct screw-in replacement for common R-30 style incandescent flood lamp and it may be used existing luminaires. In one preferred embodiment of the present invention, a lamp mounted in a recessed light luminaire for down lighting has one or more light emitting diodes (LEDs) that are thermally coupled to a heat sink having fins for cooling by ambient air. The fins are configured so that air warmed by the fins can rise inside the luminaire and transfer its heat to it. Air cooled by the luminaire is allowed to sink and may flow out of the luminaire via a gap between the heat sink and the luminaire. Fresh cooler air may be drawn in between the fins to replace out-flowing air. This process of heating and cooling of air established a natural convection flow. Natural convective air flow allows for efficient thermal communication between the heat sink and the luminaire, thereby allowing for lower LED junction temperature and longer LED lifetime.

The invention aims to reduce the cost of a structural member and improve the heat dissipation performance, and provides a semiconductor light source radiator and a light source engine. The semiconductor light source engine is characterized in that a, the structure (the casing) serves as a cooling fin, namely a radiating metal casing (1) machined and formed through punching a sheet metal (aluminum plate), so that the machining cost and material cost are reduced; b, the wall thickness of the radiating metal casing is optimized to further reduce the material cost; c, the metal side wall (2) is formed through stretching a rear metal casing (9) or / and a front metal casing (4), a ventilating window (3) adopting a louver type or staggered arrangement type structure is formed, the ventilating ratio is not less than 0.20, so that air in natural convection flows smoothly, and the radiating performance is remarkably improved; and d, a reflector (31) is equipped, and most light emitted from a semiconductor light source (6) is light reflected by the reflector, so that the light source engine can solve the problem of dazzling light.

The invention relates to a sugar liquid evaporator with sharp expansion and accelerated flow converging-diverging tubes inserted with twisted leaves. The sugar liquid evaporator is characterized in that: the sugar liquid evaporator comprises a cylindrical shell, and an upper steam chamber, an upper tube plate, sharp expansion and accelerated flow converging-diverging tubes inserted with twisted leaves, a central downcomer, a lower tube plate and a lower head which are sequentially arranged in the cylindrical shell, wherein the axis of the central downcomer is coincident with the axis of the cylindrical shell; and the bottom of the lower head is provided with a tube side sugar liquid outlet and a tube side sugar liquid inlet, the top of the upper steam chamber is provided with a tube side secondary steam outlet, and a shell side primary steam inlet and a shell side condensed water outlet are arranged on the cylindrical shell between the upper tube plate and the lower tube plate. By utilizing the local intelligent repeated displacement and the disturbance of periodic converging-diverging rib surfaces and the inserted twisted leaves of the converging-diverging tubes to main flows in the tubes and fluids close to walls of the tubes in the sugar liquid evaporator, the sugar liquid evaporator allows the concentration and the viscosity of the sugar liquid which is on a channel section and is obtained by the flow boiling evaporation under natural convection conditions to be uniformly distributed, the convective heat transfer coefficient and the convective diffusion capability of the fluids in the tubes to be substantially improved, a phenomenon that concentration distributions and concentration distributions of the sugar liquid at central fluid parts and at places close to the walls are not uniform to be improved, and the wall area scale of the sugar liquid to be reduced.

An apparatus to preferentially temper a liquid (only heat it, or, only cool it) by heat exchange with a fluid of indeterminate temperature. A tank of the liquid is plumbed to a liquid dispenser such as a water faucet, heater or chiller and has a internal heat exchanger sealed through each end. A drainpipe with a slit sleeve for double-wall safety, passes through the housing with an annular space between and is connected to a supply of fluids. A gasket seals the space forming a conduit for the liquid. One end of the housing extends from the tank for the liquid inlet. The conduit has natural convection holes into the tank controlled by convection valves which are moved by convection allowing convection only in the direction which preferentially tempers the liquid in the tank, regardless of the temperature, volume, rate, and time of flow of fluids.

The invention provides an electrical oil heater with high thermal efficiency. The electrical oil heater comprises a plurality of heat sinks which are tightly arrayed in sequence, wherein each heat sink is provided with an oil storage bag and a radiating fin; the oil storage bags in the heat sinks are merged and arrayed in sequence and are sealed to form an inner cavity used for containing conduction oil; the inner cavity is provided with an electric heating bar used for heating the conduction oil; a preset angle is formed between the radiating fins and the oil storage bags; under the angle, turbulent flow used for limiting hot air from flowing to the side edge is formed between a previous heat sink and a next heat sink, hot airflow flows from bottom to top in a one-way mode, and the effect of air natural thermal convection is effectively promoted; under the same width condition, the effective area of heat radiation is enlarged, the whole radiating effect of the electric oil heater is effectively promoted, and the energy-saving effect and high efficiency are realized.

The invention relates to a cold and heat convection radiation device and equipment. The cold and heat convection radiation device comprises a heat exchange body, a heat exchange medium channel is formed in the heat exchange body, an inlet of the heat exchange medium channel is used for being communicated with a flow inlet pipe communicated to a heat exchange source, an outlet of the heat exchange medium channel is used for being communicated with a flow outlet pipe communicated to the heat exchange source, multiple radiation grooves are formed in the outer wall of the heat exchange body, and an air convection hole is formed in the heat exchange body. The cold and heat convection radiation equipment comprises the flow inlet pipe, the flow outlet pipe, the heat exchange source and the above cold and heat convection radiation device; the flow inlet pipe and the flow outlet pipe are communicated with the heat exchange source, the inlet of the heat exchange medium channel is communicated with the flow inlet pipe, and the outlet of the heat exchange medium channel is communicated with the flow outlet pipe. The cold and heat convection radiation device and equipment have the functions of natural convection and cold and heat radiation at the same time, during use, no obvious wind feeling exits, and the comfort is high.

The invention provides a low-thermal-resistance natural convection radiator for a semiconductor refrigerator. The low-thermal-resistance natural convection radiator comprises an evaporator, a steam pipeline, a condenser, a liquid pipeline, a liquid storage device and a heat transfer working medium, wherein the evaporator comprises a steam outlet hole and a liquid inlet hole, and the condenser comprises a steam inlet hole and a liquid outlet hole; the steam outlet hole of the evaporator is connected with the steam inlet hole of the condenser through the steam pipeline; the liquid inlet hole ofthe evaporator is connected with the liquid outlet hole of the condenser through the liquid pipeline; the surface of the evaporator is a hot end mounting surface of the semiconductor refrigerator; a plurality of micro-channels arranged in a vertical array are arranged inside the condenser; the condenser is arranged above the evaporator; and the liquid storage device is arranged in the evaporator and communicates with the evaporator. According to the low-thermal-resistance natural convection radiator for the semiconductor refrigerator, the effective heat radiating area of the low-thermal-resistance natural convection radiator is large, the heat transfer capacity of a bottom layer heat transfer technology is high, and therefore the heat radiating capacity is high, and the refrigeration efficiency of the system can be effectively guaranteed.