An offset strip fin for use in compact automotive heat exchangers is disclosed. The offset strip fin has multiple transverse rows of corrugations extending in the axial direction wherein the corrugations in adjacent rows overlap in order that the oil boundary layer is continually re-started. The fin dimensions have been optimized in order to achieve superior ratio of heat transfer to pressure drop along the axial direction. In one aspect, . .an.!. .Iadd.a .Iaddend.compact concentric tube heat exchanger has an offset set strip tin located in an annular fluid flow passageway located between a pair of concentric tubes. The preferred range of lanced lengths is determined to be between 0.035" to 0.075" for periodically developed flow. Maintaining the lanced length in the regime of periodically developed flow is advantageous in that it gives a higher heat transfer coefficient than is achievable with fully developed flow. This also provides the added advantage that variations in the shape of the flow passages from the rectangular do not impact negatively on the heat transfer. .Iadd.The corrugations have top portions and bottom portions of the same width. The height of the corrugations is greater than this width. .Iaddend.

Optimized offset strip fin for use in compact heat exchangers

A core for a charge air cooler comprises inner and outer concentric tubes providing an axially extending annular passageway for flow of a fluid, preferably a liquid coolant. A first inlet and a first outlet are provided at the ends of the axial annular passageway. Arranged on an outer surface of the outer tube is at least one circumferential fluid flow passageway for flow of a fluid, preferably air. Each circumferential flow passageway is provided with a corrugated strip fin comprising a plurality of rows of corrugations. The core is combined with an outer housing to form a heat exchanger. The housing is provided with an inlet and an outlet for the fluid flowing through the circumferential flow passageways. Other embodiments are disclosed in which the heat exchanger is adapted for use with three fluids and in which additional cooling capacity is provided by the provision of coolant passageways in the housing.

Tubular charge air cooler

A heat exchanger with a plurality of stacked flat tubes and a collecting tank having a wall extending around the entire periphery of, and connected to, the end of the stacked flat tubes. A first medium may be distributed through the collecting tank and flat tubes. Internal inserts are in the flat tubes, with the inserts being bonded between the broad sides of the tubes and, in the region of connection of the tubes to the collecting tank, being configured to compensate for length changes in the stacking direction caused by temperature changes, as by recesses in connectors such as wave flanks or by corrugated wave flanks. The flat tubes with inserts such as described may be separately provided for use in manufacture of heat exchangers.

Heat exchanger with flat tubes

A windshield washer fluid heater having a housing which defines a housing chamber. A subhousing is disposed in the housing chamber. This subhousing is constructed of a thermally conductive material and divides the housing chamber into an outer housing chamber between the housing and the subhousing, and an inner housing chamber inside the subchamber. The outer housing chamber and inner housing chambers are fluidly isolated from each other. A core is disposed in the inner housing chamber thus forming an annular fluid chamber between the core and the subhousing. A washer fluid inlet on the housing is open to one end of the annular chamber while a washer fluid outlet at the other end is open to the other end of the annular chamber. An engine coolant inlet is open to the outer chamber while an engine coolant outlet is also open to the outer chamber at a position spaced from the inlet so that fluid flow into the coolant inlet flows through the outer housing chamber and to the coolant outlet. Alternatively, an electric heater is used to heat the housing chamber containing the annular fluid chamber.

Windshield washer fluid heater and system

The present invention provides a heat exchanger for transferring heat between a first working fluid and a second working fluid. The heat exchanger can include a corrugated fin positionable along a flow path of the first working fluid between adjacent tube walls and being operable to increase heat transfer between the first working fluid and the second working fluid. The fin can include a leg defined between adjacent folds. The heat exchanger can also include a plurality of convolutions extending inwardly from a distal end of the leg and terminating at different distances from the end.

Heat exchanger having convoluted fin end and method of assembling the same

A method is provided for manufacturing a concentric-tube heat exchanger which includes at least a pair of concentric tubes disposed one within the other to form an annular longitudinally extending flow channel in which a plurality of heat transfer promoting fins reside. The method includes the step of applying a radially directed force to one of the pair of concentric tubes in sufficient magnitude to permanently deform the tube into engagement with the plurality of heat transfer promoting fins.

Method of manufacturing a concentric tube heat exchanger

Procede simple et rapide de fabrication d'un echangeur de chaleur a tubes concentriques. Il comprend l'application aux tubes 20, 22, d'une force de deformation dirigee radialement d'intensite suffisante pour fournir une deformation permanente. Application a la fabrication d'echangeur de chaleur carburant-huile pour moteur a turbine a gaz.

Coffinberry George Albert

Papers

Method of manufacturing a concentric tube heat exchanger

Procede de fabrication d'un echangeur de chaleur a tubes concentriques

Verfahren zum herstellen eines konzentrischen rohrwaermeaustauschers