Feedback controlled variable conductance heat pipes
Variable conductance heat pipes feedback mechanisms for spacecraft electrical temperature control system design, using steady state analysis based performance model
Bienert, W. B.↗
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Experimental investigation of pressure wave propagation in a pipe
Temporal and spatial flow velocity profiles produced by shock tube generated pressure wave propagation in open-end pipe
Loh, M. J.↗
Experimental high performance heat pipes for the OAO-C spacecraft
Design and performance testing of arterial wick circular heat pipes for OAO-C spacecraft
Bienert, W.↗
Transient performance of electrical feedback- controlled variable-conductance heat pipes
Steady state and transient response of heat source with temperature regulated by electrical feedback controlled variable conductance heat pipe
Bienert, W. B.↗
A variable conductance heat-pipe flight experiment
Gas controlled variable conductance heat pipe for OAO-C onboard processor temperature stabilization, describing thermal performance tests under simulated flight conditions
Kirkpatrick, J. P.↗
Longitudinal friction forces in piping design
Scheme measures sliding support friction forces and incorporates them into software programs which are used to analyze piping flexibility.
Parker, C. S.↗
Restartable heat pipe
Inclusion in heat pipe of auxiliary working fluid which has considerably lower freezing point than main working fluid enables easy starting after main working fluid has been cooled to or below freezing point.
Shlosinger, A. P.↗
An electrohydrodynamic heat pipe
Dielectric liquid for transfer of heat provides liquid flow from the condenser section to the evaporator section in conventional heat pipes. Working fluid is guided or pumped by an array of wire electrodes connected to a high-voltage source.
Jones, T. B.↗
Dry ice plug for hydraulic and pneumatic pipe flushing
Development of technique to clear blockages in hydraulic and pneumatic pipes is discussed. Technique consists of using dry ice plug to separate sensitive components from flushing fluid. Diagram of equipment and principles of operation are presented.
Francino, L.↗
Use of small turbine-type flowmeters to measure flow in large pipes
Measurement of mass flow in large pipes using small turbine-type flowmeters is discussed. Experiments for determining accuracy of flowmeter and applicability to various types of flow measurement are reported. Illustration of turbine flowmeter and calibration curve are included.
Minkin, H. L.↗
Potassium Rankine cycle vapor chamber (heat pipe) radiator study
A structurally integrated vapor chamber fin (heat pipe) radiator is defined and evaluated as a potential candidate for rejecting waste heat from the potassium Rankine cycle powerplant. Several vapor chamber fin geometries, using stainless steel construction, are evaluated and an optimum is selected. A comparison is made with an operationally equivalent conduction fin radiator. Both radiators employ NaK-78 in the primary coolant loop. In addition, the Vapor Chamber Fin (VCF) radiator utilizes sodium in the vapor chambers. Preliminary designs are developed for the conduction fin and VCF concepts. Performance tests on a single vapor chamber were conducted to verify the VCF design. A comparison shows the conduction fin radiator easier to fabricate, but heavier in weight, particularly as meteoroid protection requirements become more stringent. While the analysis was performed assuming the potassium Rankine cycle powerplant, the results are equally applicable to any system radiating heat to space in the 900 to 1400 F temperature range.
Gerrels, E. E.↗
Heat pipe applications for the space shuttle.
Discussion of six specific applications for heat pipe (HP) devices on the space shuttle. These applications were chosen from 27 concepts formulated as part of a study to evaluate the potential benefits associated with HP use. The formulation process is briefly described along with the applications which evolved. The bulk of the discussion deals with the 'top' six - namely, HP radiators for waste heat rejection, an HP augmented cold rail, an HP circuit for electronic equipment cooling, modular heat sink for control of remote packages, an HP temperature control for compartments, and air-cooled equipment racks. The philosophy, physical design details, and performance data are presented for each concept along with a comparison with the baseline design where applicable.
Tawil, M.↗
Heat pipe thermal control system concept for the space station.
A program was undertaken to design and evaluate a high reliability, long life thermal control system for Space Station application. The program consisted of three sequential steps including the investigation of many thermal control elements to select the most reliable. The elements are combined into several system concepts. The most desirable approach is then selected and its characteristics are determined. The result of this project is a conceptual thermal control system design that employs heat pipes as primary components, both for heat transport and variable temperature control.
Scollon, T. R., Jr.↗
Method for casting polyethylene pipe
Short lengths of 7-cm ID polyethylene pipe are cast in a mold which has a core made of room-temperature-vulcanizable (RTV) silicone. Core expands during casting and shrinks on cooling to allow for contraction of the polyethylene.
Elam, R. M., Jr.↗
Entrainment in electrohydrodynamic heat pipes
A theoretical analysis for predicting the onset of the Kelvin-Helmholtz instability is reported. The model for the analysis is described, and the derived stability criterion are given. It is concluded that surface tension plays a role in the entrainment limit of electro hydrodynamic heat pipes. The surface of the liquid in an EHD flow structure is open, with no restriction placed on the wavenumbers of perturbations.
Jones, T. B.↗
Theoretical analysis of oxygen diffusion at startup in an alkali metal heat pipe with gettered alloy walls
The diffusion of oxygen into, or out of, a gettered alloy exposed to oxygenated alkali liquid metal coolant, a situation arising in some high temperature heat transfer systems, was analyzed. The relation between the diffusion process and the thermochemistry of oxygen in the alloy and in the alkali metal was developed by making several simplifying assumptions. The treatment is therefore theoretical in nature. However, a practical example pertaining to the startup of a heat pipe with walls of T-111, a tantalum alloy, and lithium working fluid illustrates the use of the figures contained in the analysis.
Tower, L. K.↗
Heat pipe investigations
Techniques associated with thermal-vacuum and bench testing, along with flight testing of the OAO-C spacecraft heat pipes are outlined, to show that the processes used in heat transfer design and testing are adequate for good performance evaluations.
Marshburn, J. P.↗
Electrohydrodynamic heat pipe research
Experimental and theoretical applications to electrohydrodynamic heat pipe (EHDHP) research are presented. Two problems in the research which are discussed are the prediction of the effective thermal conductance of an EHDHP with threaded grooves for fluid distribution to the evaporator of an EHDHP. Hydrodynamic equations are included along with a discussion of boundary conditions and burn-out conditions. A discussion of the theoretical and experimental results is presented.
Jones, T. B.↗