Development of a high-effectiveness slotted plate cryogenic heat exchanger

Object of the present study is an experimental determination of energy efficiency parameters of air handling unit with integrated air to air heat exchanger: effectiveness of air to air heat exchanger, coefficient of performance and specific fan power of air handling unit. A daily performance of air handling unit is conducted. Effectiveness of supply side of air to air heat exchanger in range of 42.4 % to 52.5 % is received. Coefficient of performance in range of 1.50 to 2.08 and specific fan power of air handling unit in range of 1.39 kW/(m3/s) to 2.08 kW/(m3/s) are received. It was found experimentally that effectiveness of air to air heat exchanger depends on values of mass flow of supply and the exhaust air. High values of mass flow of the exhaust air responds to high effectiveness of supply side of air to air heat exchanger.

Download Full-text

Design of a compact mesh-based high-effectiveness counter-flow heat exchanger and its integration in remote cooling systems

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2021.122107 ◽

2022 ◽

Vol 183 ◽

pp. 122107

Author(s):

A. Onufrena ◽

T. Koettig ◽

J. Bremer ◽

T. Tirolien ◽

T. Dorau ◽

...

Keyword(s):

Heat Exchanger ◽

Counter Flow ◽

Cooling Systems ◽

High Effectiveness ◽

Flow Heat

Download Full-text

Direct Observation of Heat Exchanger Deposits by Cross Sectioning

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061835 ◽

1967 ◽

Vol 25 ◽

pp. 364-365

Author(s):

R. W. Anderson ◽

D. L. Senecal

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Heat Exchanger ◽

Direct Observation ◽

Cross Sections ◽

Preparation Method ◽

Specimen Preparation ◽

Flowing Water ◽

Transmission Electron ◽

Deposit Layer

A problem was presented to observe the packing densities of deposits of sub-micron corrosion product particles. The deposits were 5-100 mils thick and had formed on the inside surfaces of 3/8 inch diameter Zircaloy-2 heat exchanger tubes. The particles were iron oxides deposited from flowing water and consequently were only weakly bonded. Particular care was required during handling to preserve the original formations of the deposits. The specimen preparation method described below allowed direct observation of cross sections of the deposit layers by transmission electron microscopy.The specimens were short sections of the tubes (about 3 inches long) that were carefully cut from the systems. The insides of the tube sections were first coated with a thin layer of a fluid epoxy resin by dipping. This coating served to impregnate the deposit layer as well as to protect the layer if subsequent handling were required.

Download Full-text