Fluid-handling apparatus with corrosion-erosion coating and method of making same

Abstract

Inlet surfaces of a fluid-handling apparatus, such as a heat exchanger, are often prone to corrosion and erosion due to the high velocities of incoming fluid. The present disclosure includes a fluid-handling apparatus with a plurality of wetted surfaces of which a first portion is corrosion-erosion prone and a second portion is non-corrosion-erosion prone. The first portion is coated with a corrosion-erosion coating that is harder than the first portion. Less than all of the wetted surfaces are coated.

Description

TECHNICAL FIELD [0001] The present invention relates generally to fluid-handling apparatuses, and more specifically to heat exchangers with a corrosive-erosion resistant coating and a method of making same. BACKGROUND [0002] There are various uses for heat exchangers known in the art. For instance, heat exchangers, often referred to as charge air coolers, use a coolant to cool compressed air exiting a turbocharger before the air is injected into an engine. In commercial or pleasure marine crafts, sea water is often used as the coolant. The sea water will flow into a sea water inlet manifold before flowing into a plurality of sea water passages, and the air will flow into an air inlet manifold before flowing into a plurality of air passages. The sea water passages are generally oriented perpendicularly to the air passages such that the heat within the air can be exchanged with sea water through walls of the sea water and the air passages. The sea water passages and the air passages a...

AI Technical Summary

Problems solved by technology

Using sea water as the coolant can present a challenge due to the sea water's corrosive nature and tendency to contain abrasives such as sand and silt and other forms of deposits including sea weeds, sea shell fragments, animal components, etc.

Due to the high velocity and the corrosive nature of the sea water, the sea water contacting the inlet surfaces will impinge the surfaces.

The impingement can cause corrosion and erosion, and thus, damage the surfaces of the inlet manifold, including a core surface defining inlets of the sea water passages.

Over time, the damage can lead to holes, causing leakage of the sea water and, thus, premature failure of the heat exchanger.

For instance, the corrosion and erosion can create holes in the surfaces separating the hot air passages and the sea water inlet manifold or passages, causing leaking of the sea water into the air passages.

The turbulent flow causes more impingement which leads to corrosion and erosion than does the laminar flow.

Manufacturing heat exchanger components from corrosion and erosion-resistant materials can be more costly than using traditional materials.

Further, the corrosion-erosion resistant materials can introduce a heat transfer penalty due to their reduced thermal conductivity.

Thus, by manufacturing all of the sea water wetted components out of corrosion-erosion resistant materials, rather than just the corrosion-erosion prone sea water inlet surfaces, the cost of the heat exchanger and the heat transfer penalty is unnecessarily increased while potentially also reducing heat transfer performance.

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