PROTRACED COUNTERINSURGENCY: CHINESE COIN STRATEGY IN XINJIANG by MAJ J. Scott LaRonde, USA, 95 pages. In 1949, following the conclusion of its revolutionary war against the Chinese Nationalist forces, the People’s Liberation Army (PLA) peacefully occupied China’s western most province of Xinjiang. For nearly sixty years, the PLA has conducted a counterinsurgency against several, mostly Uyghur-led, separatist movements. Despite periods of significant violence, particularly in the early 1950s and again in the 1990s, the separatist forces have not gained momentum and remained at a level one insurgency. Mao ZeDeng is revered as a master insurgent and the father of Fourth Generation Warfare. Strategists in armies worldwide study his writings on revolutionary and guerilla warfare. This monograph concludes that Mao, as well as the communist leaders who followed him, was also successful at waging protracted counterinsurgency. For nearly sixty years, separatist movements in Xinjiang, Tibet, and Taiwan have all failed. This monograph analyzes the conflict in Xinjiang and concludes that the Chinese continue to defeat the separatist movement in Xinjiang through a strategy that counters Mao’s seven fundamentals of revolutionary warfare.

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Publisher Summary Impinging liquid jets have been demonstrated to be an effective means of providing high heat or mass transfer rates in industrial transport processes. This chapter summarizes the available analytical and experimental work in the area with the objective of correlating the research findings. Significant progress has been made in understanding the fundamentals of heat, mass, and momentum transport in these systems. This chapter suggests that, there is considerable need for further research in liquid jet array applications, both in submerged and free-surface jet configurations. Cross-flow effects in these systems, which have been quite well characterized for submerged jets, have received only superficial treatment for free-surface jets. The physical phenomena are highly complex, requiring careful experimental investigation.

Single-Phase Liquid Jet Impingement Heat Transfer

Review of computational studies on boiling and condensation

Universal approach to predicting saturated flow boiling heat transfer in mini/micro-channels - Part II. Two-phase heat transfer coefficient

Boiling water in small channels that are formed along turbine blades has been examined since the 1970s as a means to dissipating large amounts of heat. Later, similar geometries could be found in cooling systems for computers, fusion reactors, rocket nozzles, avionics, hybrid vehicle power electronics, and space systems. This paper addresses (a) the implementation of two-phase microchannel heat sinks in these applications, (b) the fluid physics and limitations of boiling in small passages, and effective tools for predicting the thermal performance of heat sinks, and (c) means to enhance this performance. It is shown that despite many hundreds of publications attempting to predict the performance of two-phase microchannel heat sinks, there are only a handful of predictive tools that can tackle broad ranges of geometrical and operating parameters or different fluids. Development of these tools is complicated by a lack of reliable databases and the drastic differences in boiling behavior of different fluids in small passages. For example, flow boiling of certain fluids in very small diameter channels may be no different than in macrochannels. Conversely, other fluids may exhibit considerable “confinement” even in seemingly large diameter channels. It is shown that cutting-edge heat transfer enhancement techniques, such as the use of nanofluids and carbon nanotube coatings, with proven merits to single-phase macrosystems, may not offer similar advantages to microchannel heat sinks. Better performance may be achieved by careful optimization of the heat sink’s geometrical parameters and by adapting a new class of hybrid cooling schemes that combine the benefits of microchannel flow with those of jet impingement. [DOI: 10.1115/1.4005300]

Two-Phase Microchannel Heat Sinks: Theory, Applications, and Limitations

Experiments were performed to investigate single-phase heat transfer from a smooth 12.7×12.7 mm 2 simulated chip to a two-dimensional jet of dielectric Fluorinert FC-72 liquid issuing from a thin rectangular slot into a channel confined between the chip surface and nozzle plate

Cooling of a multichip electronic module by means of confined two-dimensional jets of dielectric liquid

Jet impingement is encountered in numerous applications demanding high heating or cooling fluxes. Examples include annealing of metal sheets and cooling of turbine blades, x-ray medical devices, laser weapons, and fusion blankets. The attractive heat transfer attributes of jet impingement have also stimulated research efforts on cooling of high-heat-flux microelectronic devices. These devices are fast approaching heat fluxes in excess of 100 W/cm[sup 2], which have to be dissipated using coolants that are both electrically and chemically compatible with electronic components. Unfortunately, fluids satisfying these requirements tend to possess poor transport properties, creating a need for significant enhancement in the heat transfer coefficient by such means as increased coolant flow rate and phase change. The cooling problem is compounded by a need to cool large arrays of heat sources in minimal volume, and to reduce the spacing between adjacent circuit boards. These requirements place severe constraints on the packaging of jet impingement cooling hardware.

Enhancement of Single-Phase Heat Transfer and Critical Heat Flux From an Ultra-High-Flux Simulated Microelectronic Heat Source to a Rectangular Impinging Jet of Dielectric Liquid

Experiments were performed to investigate single-phase heat transfer froma smooth 12.7 {times} 12.7 mm{sup 2} simulated chip to a two-dimensional jet of dielectric Fluorinert FC-72 liquid issuing from a thin rectangular slot into a channel confined between the chip surface and nozzle plate. The effects of jet width, confined channel height, and impingement velocity have been examined. Channel height had a negligible effect ont eh theat transfer performance of the jet for the conditions of the present study. A correlation for the convective heat transfer coefficient is presented as a function of jet, width, heat length, flow velocity, and fluid properties. A self-contained multichip cooling module consisting of a 3 {times} 3 array of heat sources confirmed the uniformity and predictability of cooling for each of the nine chips, and proved the cooling module is well suited for packaging large arrays of high-power density chips.

D. C. Wadsworth

Papers

Cooling of a multichip electronic module by means of confined two-dimensional jets of dielectric liquid

Enhancement of Single-Phase Heat Transfer and Critical Heat Flux From an Ultra-High-Flux Simulated Microelectronic Heat Source to a Rectangular Impinging Jet of Dielectric Liquid

Cooling of a Multichip Electronic Module by Means of Confined Two-Dimensional Jets of Dielectric Liquid