Heat transfer and fouling deposition investigation on the titanium coated heat exchanger surface

The paper focuses on hydrocarbon fuel cooling in launch vehicles, specifically considering experimental technique and results obtained during investigation of one of the primary heat exchanger parameters, that is, heat transfer coefficient of the heat exchanger surface. We present a model of efficient hydrocarbon fuel cooling by means of intensifying heat transfer on the external heat exchanger surface due to nitrogen sparging causing active motion in the liquid heat carrier. We obtained quantitative data regarding heat transfer on the external surface of a helical-coil heat exchanger located in a two-phase medium consisting of antifreeze and nitrogen, in the temperature range of 243--293 K. We derived a similarity equation for calculating heat transfer coefficient on the external heat exchanger surface, which is required to determine the heat exchanger surface area and to compute heat transfer from hydrocarbon fuel to the two-phase medium consisting of antifreeze and nitroge.

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Mineral Fouling Control by Underwater Plasma Discharge in a Heat Exchanger

Journal of Heat Transfer ◽

10.1115/1.4003116 ◽

2011 ◽

Vol 133 (5) ◽

Cited By ~ 4

Author(s):

Yong Yang ◽

Hyoungsup Kim ◽

Alexander Fridman ◽

Young I. Cho

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Hard Water ◽

Plasma Discharge ◽

Mineral Contents ◽

Fouling Control ◽

Spark Discharges ◽

Mineral Fouling ◽

Pulsed Spark Discharge ◽

Heat Exchanger Surface

The excessive mineral contents in water circulation systems could cause severe fouling in heat transfer equipment. The present study investigated the effect of underwater pulsed spark discharges on the mitigation of mineral fouling in a concentric counterflow heat exchanger. Artificial hard water with calcium carbonate hardness of 250 mg/L was used with velocity ranging from 0.1 m/s to 0.5 m/s and zero blowdown. Fouling resistances decreased by 50–72% for the plasma treated cases compared with the values for no-treatment cases, indicating that the pulsed spark discharge could significantly mitigate the mineral fouling on the heat exchanger surface.

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Analysis of Heat Transfer Surface Geometries for Dry Cooling Tower Applications

Journal of Engineering for Power ◽

10.1115/1.3230344 ◽

1980 ◽

Vol 102 (4) ◽

pp. 807-812 ◽

Cited By ~ 1

Author(s):

Ali Montakhab

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Heat Exchangers ◽

Cooling Tower ◽

Heat Transfer Surface ◽

Per Se ◽

Fin Tube ◽

Dry Cooling Tower ◽

Heat Exchanger Surface ◽

Dry Cooling

An analysis of heat exchanger surface geometries for the purpose of reducing dry cooling tower cost is presented. Two sets of results are derived. The first set can be used to evaluate heat transfer surface geometries in an attempt to select those most suitable for dry cooling tower applications. The second set of results can be used to direct research and development efforts toward developing better geometries for dry cooling tower applications. The first set of results is general and is applicable to all heat exchanger surface geometries. The second set is valid only for helical round or continuous fins having smooth, serrated, or cut fins and for staggered and in-line tube arrangements. The methods developed in this paper are not restricted to dry cooling towers per se, but are valid for other applications of fin tube heat exchangers as well.

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