Ships and marine technology. Marine cranes. Design requirements for low temperature operation

In this study, low temperature Organic Rankine Cycle (ORC) systems with single and two-stage turbine are proposed for the production of electricity. The refrigerant R-134a is selected as working fluid based on peak temperature of the cycle for solar and geothermal applications. The design criteria of ORC system is introduced and explained in detail. The radial inflow turbine is selected to satisfy the design requirements. The cycle performance is taken as a key point in the design criteria. The system performance map is constructed based on both velocity triangles and approximate efficiency of turbine. The procedures for turbine and cycle design are introduced in detail. The components of cycle and turbine are modeled using baseline correlations via real gas tables and macros created on Excel for the refrigerant, R134a. Finally, the turbine geometry is optimized to attain maximum turbine efficiency via MATLAB optimization toolbox.

Download Full-text

Development of Meter-Scale U-Shaped and O-Shaped Oscillating Heat Pipes for GAPS

Journal of Astronomical Instrumentation ◽

10.1142/s2251171714400042 ◽

2014 ◽

Vol 03 (02) ◽

pp. 1440004 ◽

Cited By ~ 9

Author(s):

Shun Okazaki ◽

Hideyuki Fuke ◽

Yoshiro Miyazaki ◽

Hiroyuki Ogawa

Keyword(s):

Low Temperature ◽

Heat Transport ◽

Thermal Conductance ◽

Heat Pipes ◽

Working Fluid ◽

Gravity Effect ◽

Performance Difference ◽

Oscillating Heat Pipe ◽

Design Requirements ◽

First Time

A meter-scale Oscillating Heat Pipe (OHP) has been developed for the General Anti-Particle Spectrometer (GAPS) project. Two types of OHP routing, U-shaped and O-shaped, have been investigated. For the operation at low temperature, R410A was used as the working fluid. As the result of the investigation, we verified for the first time that both the meter-scale U-shaped and O-shaped OHPs can transfer heat under gravity in a wide temperature range between 20°C and -60°C. Generally, the O-shaped OHP showed better performance than the U-shaped OHP. Both OHP models showed good thermal conductance and a good amount of heat transport under the particular sets of conditions which meet the design requirements. In order to clarify the drive force to operate OHP to further improve the OHP design, the performance difference between the U-shaped and the O-shaped models has been interpreted in terms of the gravity effect and the pressure loss.

Download Full-text