Apparatus and method for analyzing heat-transferring fluid

An exemplary apparatus (10) is for analyzing a heat-transferring nano-fluid (20) with a view to obtaining information on heat-transferring properties of the nano-fluid. Typically, the nano-fluid is used for heat pipes. The apparatus includes an evaporating device (100) and a detecting device (200). The evaporating device is configured for preparing a gaseous sample (20′) of the nano-fluid for analyzing. The evaporating device includes a container (110) configured for containing the nano-fluid, and a temperature controller (120). The container has a first opening (112) allowing vaporized nano-fluid to exit therethrough. The temperature controller is configured for heating the nano-fluid in the container up to a predetermined temperature, and maintaining the nano-fluid at the predetermined temperature. The detecting device is configured for generating a laser light and receiving an optical emission from the gaseous sample, thus enabling heat-transferring properties of the nano-fluid to be analyzed. A related method is also provided.

BACKGROUND

1. Technical Field

The present invention relates to an apparatus and a method for analyzing a heat-transferring fluid with a view to learning about heat-transferring properties of the heat-transferring fluid, and particularly to an apparatus and a method for analyzing a heat-transferring nano-fluid typically used in heat pipes.

2. Related Art

A heat pipe is a heat-transferring mechanism that can transport large quantities of heat between a relatively hot interface and a relatively cold interface where the difference in temperature is very small. A vaporizable liquid is typically employed within the heat pipe for transferring the heat between the hot interface and the cold interface. Nano-fluids that contain nano-particles have been recently developed as an improved kind of heat-transferring fluid. The nano-particles provide the nano-fluid with a thermal conductivity higher than that of a conventional vaporizable liquid. Thus nano-fluids are now commonly employed in place of conventional heat-transferring fluids in the manufacture of heat pipes. It is widely known that adding nano-particles to a base fluid can dramatically increase the heat-transferring properties of the base fluid. However, precisely analyzing the relationship between the quantity and type of nano-particles added and the resulting heat-transferring properties yielded is not easy.

Therefore, what is needed is an apparatus and a method for analyzing a heat-transferring fluid that contains nano-particles, the heat-transferring fluid being typically used for heat pipes.

SUMMARY

In order to analyze a heat-transferring fluid with a view to obtaining information on heat-transferring properties of the heat-transferring fluid, an apparatus adapted for doing so is provided. The heat-transferring fluid contains nano-particles, and is referred to as a nano-fluid. Typically, the heat-transferring fluid is used for heat pipes. The apparatus includes an evaporating device and a detecting device. The evaporating device is configured for preparing a gaseous sample of the heat-transferring fluid for analyzing. The evaporating device includes a container configured for containing the heat-transferring fluid, and a temperature controller. The container has a first opening allowing vaporized heat-transferring fluid to exit therethrough. The temperature controller is configured for heating the heat-transferring fluid in the container up to a predetermined temperature, and maintaining the heat-transferring fluid at the predetermined temperature. At the predetermined temperature, the heat-transferring fluid vaporizes, with the vapor attaining a pressure dynamically balanced with that of ambient air. The detecting device is configured for generating a laser light and receiving an optical emission from the gaseous sample, thus enabling heat-transferring properties of the heat-transferring fluid to be analyzed.

An advantage of the apparatus is that it is easy to handle, accurate, and provides fast data. A related method is also provided herein.

Corresponding reference characters indicate corresponding parts throughout the first drawing. The exemplifications set out herein illustrate at least one preferred embodiment of the present apparatus and method, in one form, and such exemplifications are not to be construed as limiting the scope of such apparatus or method in any manner.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Reference will now be made to the drawings to describe the preferred embodiments of the present apparatus and method in detail.

Referring toFIG. 1, this shows an apparatus10configured for analyzing a heat-transferring fluid20containing nano-particles (not shown), with a view to obtaining information on heat-transferring properties of the heat-transferring fluid20. This kind of heat-transferring fluid20is referred to as a nano-fluid. The nano-particles can for example be nano-metal particles, such as nano-copper particles or nano-gold particles, and the heat-transferring fluid20is typically employed in heat pipes. However, other nano-particles such as nano-carbon particles that have good thermal conductivity can also be used in connection with the apparatus10. The apparatus10mainly includes an evaporating device100configured for preparing a gaseous sample20′ of the heat-transferring fluid20, and a detecting device200configured for detecting photons emitted from the gaseous sample20′. The detected photons can then be analyzed in order to obtain information on heat-transferring properties of the heat-transferring fluid20.

The evaporating device100includes a container110and a temperature controller120. The container110is configured for containing the heat-transferring fluid20to be analyzed. The container110includes at least a first opening112for allowing the gaseous sample20′ to escape upwardly therefrom. The temperature controller120is configured for maintaining the heat-transferring fluid20in the container110at a predetermined temperature. At the predetermined temperature, the heat-transferring fluid20vaporizes, with the vapor attaining a pressure greater than that of ambient air. Thereby, the vaporized heat-transferring fluid20exits the first opening112and generates the gaseous sample20′ thereat.

It is to be noted that in general, different heat-transferring fluids have different liquid-gas phase conversion points. The quantity and kind of nano-particles added in a base fluid also changes the phase conversion point of the base fluid. Accordingly, the predetermined temperature referred to above is preferably determined according to the practical liquid-gas phase conversion point of a base fluid comprised in the heat-transferring fluid, and according to the quantity and kind of nano-particles used in the base fluid.

According to another embodiment of the apparatus10, the container110further includes a second opening114. The second opening114is provided at a bottom of the container110, for allowing a carrier gas30to be inputted therethrough into the container110. In this embodiment, the above-mentioned predetermined temperature may be lowered somewhat, depending on an amount of extra pressure that is introduced by inputting the carrier gas30.

The temperature controller120includes a liquid bath device. Preferably, the liquid bath device is a hot water bath device including hot water122therein. The container110is set in the hot water bath, so the heat-transferring fluid20in the container110is surrounded by the hot water122and can exchange heat with the hot water122.

The detecting device200includes a laser light source210and a photon detector. In the exemplary embodiment, the photon detector is an optical emission detector220. The laser light source210is configured for providing a laser light212that illuminates the gaseous sample20′ located over the first opening112of the container110. The optical emission detector220is configured for detecting and receiving photons emitted from the gaseous sample20′ when the gaseous sample20′ is illuminated by the laser light212. In the exemplary embodiment, the photons constitute an optical emission222.

According to another embodiment of the apparatus10, the apparatus10further includes a guiding means230such as a reflecting mirror. The guiding means230is configured for directing the optical emission222from the gaseous sample20′ to the optical emission detector220. The apparatus10preferably further includes a filter224positioned in a path of the optical emission222immediately in front of the optical emission detector220, for reducing or eliminating any possible optical noise emissions included in the optical emission222.

According to one embodiment of the apparatus10, the optical emission detector220includes a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS) device. The optical emission detector220can alternatively further include a converging lens226, which positioned in a path of the optical emission222adjacent to the filter224. The converging lens226is configured for collecting more optical emissions222, and thereby improving a sensitivity of the optical emission detector220.

FIG. 2is a flowchart of a method for analyzing a heat-transferring fluid, with a view to obtaining information on heat-transferring properties of the heat-transferring fluid, according to an exemplary embodiment of the present invention. The method is typically performed using the above-described apparatus10.

Referring also toFIG. 1, the method will be described in relation to analyzing the heat-transferring fluid20. The method mainly includes the following steps. Firstly, the heat-transferring fluid20is filled into the container110having the first opening112. Secondly, the heat-transferring fluid20is heated by the hot water bath120up to and stably maintained at a predetermined temperature, which is equal to a liquid-gas phase conversion point of the heat-transferring fluid20. At such temperature, the heat-transferring fluid20is vaporized, and the vaporized heat-transferring fluid20exits the first opening112and thus provides the gaseous sample20′. Thirdly, the laser light212illuminates the gaseous sample20′ over the first opening112, and atoms of the gaseous sample20′ emit photons. In an exemplary embodiment, the photons constitute the optical emission222. The optical emission222can be considered to contain information on the heat-transferring properties of the heat-transferring fluid20. Finally, the optical emission222is detected by an photon detector. In an exemplary embodiment, the photon detector is the optical emission detector220. The results of detection can then be analyzed to obtain information on the heat-transferring properties of the heat-transferring fluid20.

According to another embodiment, the method further includes inputting the carrier gas30through the second opening114at the bottom of the container110, for facilitating vaporization of the heat-transferring fluid20. The carrier gas30is preferably selected from the group consisting of nitrogen, argon, helium, neon, krypton, and xenon. In this embodiment, the above-described predetermined temperature may be equal to or lower than the liquid-gas phase conversion point of the heat-transferring fluid20.

A more detailed exemplary embodiment of the method for analyzing a heat-transferring fluid is as follows. In carrying out the method, the above-described apparatus10can be utilized under normal room temperature and pressure conditions. The heat-transferring fluid20is prepared and filled in the container10. Then the thermal controller120is activated to heat the container110and the heat-transferring fluid20contained therein up to a predetermined temperature. In this exemplary embodiment, the predetermined temperature is slightly lower than a liquid-gas phase conversion point of the heat-transferring fluid20. After the heat-transferring fluid20has been stably maintained at the predetermined temperature, a carrier gas30is inputted into the container110through the second opening114thereof. The carrier gas114is preferably nitrogen, which is relatively inexpensive. However, other gases such as argon, helium, neon, krypton, or xenon may be employed as the carrier gas30. The heat-transferring fluid20is thus vaporized, and a mixture of the carrier gas30and the vaporized heat-transferring fluid20moves toward the first opening112. The vaporized heat-transferring fluid20exits the first opening112and provides the gaseous sample20′ of the heat-transferring fluid20thereat.

The laser light source210generates a laser light212to illuminate the gaseous sample20′. When illuminated by the laser light212, unsaturated outer-shell electrons of atoms contained in the gaseous sample20′ absorb photons of the laser light212, and are excited to jump from a basic level of energy to a higher metastable level of energy. The outer-shell electrons cannot remain at the metastable level for long. When any outer-shell electron jumps back to the basic level, a photon having an energy that is the difference between the basic level of energy and the metastable level of energy is emitted. Such a photon is considered as containing information related to the physical properties of the matter which emitted the photon. For example, different atoms emit photons of different wavelengths. A plurality of emitted photons constitutes the optical emission222, which is reflected by the guiding means230to the optical emission detector220. By performing appropriate analysis of the optical emission222collected by the optical emission detector220, heat-transferring properties of the heat-transferring fluid20can be obtained.

While the invention has been described as having preferred and exemplary embodiments, further modifications within the spirit and scope of this disclosure are intended to be included. This disclosure is intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this disclosure is intended to cover such departures from the described embodiments as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims or equivalents thereof.