Conveners
C3OrK - Hydrocarbons and Mixtures: Fluid Mechanics and Heat Transfer
- Amir Jahromi (NASA/GSFC)
- Marcel ter Brake (University of Twente)
Cryogenic mixed refrigerant cycles (CMRCs) offer a cost- and energy-efficient cooling method for the temperature range between 60 and 200 K. The performance of CMRCs is strongly influenced by entropy production in the main heat exchanger. High efficiencies thus require small temperature gradients among the fluid streams, as well as limited pressure drop and axial conduction. As temperature...
Zeotropic mixtures never have the same liquid and vapor composition in the liquid-vapor equilibrium. Also, the bubble and the dew point are separated; this gap is called glide temperature (Tglide). Those characteristics have made these mixtures suitable for cryogenics Joule-Thomson (JT) refrigeration cycles. Zeotropic mixtures as working fluid in JT cycles improve their performance in an...
As a more efficient and environment-friendly refrigerant alternative, hydrocarbons have good environmental characteristics and high thermodynamic performances. They have been used as refrigerant in refrigerator and air-conditioning system. The mechanisms of the pressure drop are intimately linked with the prevailing two phase flow regime. Therefore, it is necessary to carried out a universal...
This work proceeds a numerical study of inclination effect on the heat transfer performance of a tubular heat exchanger. This equipment is widely used in the gasification process of a floating liquefied natural gas system (FLNG) to exploit cold energy from boiled-off liquefied natural gas (BOG). The inclination comes from the FLNG floating in an ocean environment. The finite volume...
The efficient re-gasification of cryogen is a crucial process in many cryogenic installations. It is especially important in the case of LNG evaporators used in stationary and mobile applications (e.g. marine and land transport). Other gases, like nitrogen or argon, are used as protective atmospheres, and can be obtained at highest purity after re-gasification in their liquid states. This...
Counter-flow plate-fin heat exchangers are commonly utilized in cryogenic applications due to their high effectiveness and compact size. For helium liquefaction/refrigeration systems, conventional design theory is no longer applicable and cryogenic heat exchangers are usually sensitive to longitudinal heat conduction, heat in-leak from surrounding and variable fluid properties. Governing...
