Experimental study of a Capillary Pumped Loop assisted with a mechanical pump placed at the evaporator inlet

Results of an experimental study of a full-scale passive solar hot water heating system utilizing a boiling collector are presented. The self-pumping system alternates between two modes of operation. During the run cycle, vapor pressure drives the evaporated refrigerant downward from the collector to the condenser. Once a preset quantity of refrigerant is condensed, vapor pressure is again used to force the return of the condensate to the collector during the pump cycle. In order to assess the thermal penalty of self-pumping operation, the system is also operated with a mechanical pump. Daily operating characteristics and seasonal performance are discussed. Performance of the self-pumping system is strongly influenced by the duration of the pump cycle. The average thermal loss attributed to self-pumping during one heating season in Fort Collins, Colo. is approximately nine percent of the solar energy incident on the collector. Refinement of the system design, including individual components, is required to reduce losses and improve performance.

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Experimental study of a capillary pumped loop in comparison with the prediction of a 3D CFD

International Journal of Low-Carbon Technologies ◽

10.1093/ijlct/ctu025 ◽

2014 ◽

Vol 11 (2) ◽

pp. 184-192

Author(s):

Nikolaos A. Avgerinos ◽

Dionissios P. Margaris ◽

Demos T. Tsahalis

Keyword(s):

Experimental Study ◽

Capillary Pumped Loop

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Experimental study of pressure rise at the evaporator of capillary pumped loop with acetone and water as working fluids

Experimental Thermal and Fluid Science ◽

10.1016/j.expthermflusci.2017.05.004 ◽

2017 ◽

Vol 87 ◽

pp. 161-170 ◽

Cited By ~ 1

Author(s):

Paweł Szymański ◽

Dariusz Mikielewicz

Keyword(s):

Experimental Study ◽

Pressure Rise ◽

Capillary Pumped Loop ◽

Working Fluids

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Experimental study on the operating characteristics of a capillary pumped loop with a flat evaporator

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2009.09.032 ◽

2010 ◽

Vol 53 (1-3) ◽

pp. 268-275 ◽

Cited By ~ 11

Author(s):

Wukchul Joung ◽

Hyungjin Hwang ◽

Jinho Lee

Keyword(s):

Experimental Study ◽

Operating Characteristics ◽

Capillary Pumped Loop ◽

Flat Evaporator

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Studies on Water in the Hydration Chamber of a Modified Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069715 ◽

1970 ◽

Vol 28 ◽

pp. 544-545

Author(s):

R. C. Moretz ◽

G. G. Hausner ◽

D. F. Parsons

Keyword(s):

Thin Film ◽

Thin Films ◽

Electron Microscope ◽

Steady State ◽

Room Temperature ◽

Small Mass ◽

Equilibrium Pressure ◽

Biological Objects ◽

Mechanical Pump ◽

Differential Pumping

Use of the electron microscope to examine wet objects is possible due to the small mass thickness of the equilibrium pressure of water vapor at room temperature. Previous attempts to examine hydrated biological objects and water itself used a chamber consisting of two small apertures sealed by two thin films. Extensive work in our laboratory showed that such films have an 80% failure rate when wet. Using the principle of differential pumping of the microscope column, we can use open apertures in place of thin film windows.Fig. 1 shows the modified Siemens la specimen chamber with the connections to the water supply and the auxiliary pumping station. A mechanical pump is connected to the vapor supply via a 100μ aperture to maintain steady-state conditions.

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Experimental study on the restoration from a tilt-azimuth series for improvement in resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010013955x ◽

1995 ◽

Vol 53 ◽

pp. 636-637

Author(s):

Norio Baba ◽

Norihiko Ichise ◽

Syunya Watanabe

Keyword(s):

Experimental Study ◽

Spherical Aberration ◽

Incident Beam ◽

Optical Parameters ◽

Beam Tilting ◽

Illumination Method ◽

Restoration Method ◽

Illumination Mode

The tilted beam illumination method is used to improve the resolution comparing with the axial illumination mode. Using this advantage, a restoration method of several tilted beam images covering the full azimuthal range was proposed by Saxton, and experimentally examined. To make this technique more reliable it seems that some practical problems still remain. In this report the restoration was attempted and the problems were considered. In our study, four problems were pointed out for the experiment of the restoration. (1) Accurate beam tilt adjustment to fit the incident beam to the coma-free axis for the symmetrical beam tilting over the full azimuthal range. (2) Accurate measurements of the optical parameters which are necessary to design the restoration filter. Even if the spherical aberration coefficient Cs is known with accuracy and the axial astigmatism is sufficiently compensated, at least the defocus value must be measured. (3) Accurate alignment of the tilt-azimuth series images.

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