Showing papers on "Heat pipe published in 2019"
TL;DR: In this article, an effective battery thermal management system solution is discussed in terms of the maximum temperature and maximum temperature difference of the batteries and an effective BTMS that complements the disadvantages of each system is discussed.
585 citations
TL;DR: In this article, the effects of temperature on the battery performance from three aspects: low temperature, high temperature and differential temperature are discussed with the main emphasis on battery modeling methods and thermal management strategies.
517 citations
TL;DR: In this paper, the effect of porosity and pore density on heat transfer, thermal conductivity, specific heat, latent heat and charging/discharging time are critically reviewed.
336 citations
TL;DR: In this article, a thermal management module with a sandwich structure consisting of a battery, phase change material, and heat pipe is assembled, and a lumped thermal model is built to consider the coupling of battery heat generation.
221 citations
TL;DR: A review of the major studies on the hybrid heat transfer enhancement techniques can be found in this paper, where it was found that best enhancement is achieved via the hybrid application of the heat pipe with fins or metal foam.
194 citations
TL;DR: In this paper, a thermal management system based on heat pipes is proposed for a battery module with cylindrical cells, and a computational fluid dynamics model is built for the BTMS and validated with experimental results.
123 citations
TL;DR: In this paper, an evacuated heat pipe solar collector (HPSC) was investigated experimentally by means of X-ray diffraction (XRD), Fourier transform-infrared (FT-IR), scanning electron microscopy (SEM), and UV-visible analysis.
118 citations
TL;DR: In this article, the state-of-the-art cooling methods of photovoltaic (PV) modules and the performance of the radiative cooling method in detail are evaluated.
Abstract: This paper reviews the state-of-the-art cooling methods of photovoltaic (PV) modules and evaluates the performance of the radiative cooling method in detail. Higher operating temperatures of PV modules cause degradation of conversion efficiency and long-term reliability. To overcome this drawback, active or passive cooling methods using heat pipe, natural/forced air flow, forced water flow, phase change material, direct liquid immersion/submerging, and passive heat sink have been studied. In this paper, the methodologies and cooling effects of various cooling methods in the literature are summarized to provide a comprehensive overview of the current cooling technologies. Then, the performance of the radiative cooling method, which is simple and passive (zero power consumption) method, is quantitatively evaluated based on a detailed heat transfer model considering sky radiation properties in four typical climate conditions. Daily heat budgets of the PV modules with different surface emissivity spectra are simulated to estimate the solar cell temperature. The results indicate that modification of the surface emissivity spectrum hardly contribute to the radiative cooling enhancement under any climate conditions, as compared to the conventional glass cover. The present findings serve as a guide for future research and development of better cooling methods.
118 citations
TL;DR: In this article, an experimental research on the thermal efficiency of an evacuated tube solar collector (ETSC) working with a nano-suspension of carbon nanotubes dispersed in distillated water is presented.
Abstract: This article presents the results of an experimental research on the thermal efficiency (TE) of an evacuated tube solar collector (ETSC) working with a nano-suspension of carbon nanotubes dispersed in distillated water. The efficacy of filling ratio (FR) of the heat pipes; the tilt angle (TA) of the collector, and the dispersion mass fraction of the carbon nanotubes within the distillated water on the TE of the collector was investigated. A model was developed based on the response surface methodology (RSM) to optimize the operating conditions in order to maximize the TE of the collector. The accuracy of the RSM model was verified with some additional experiments. It was found that the RSM model is able to optimize the TE of a collector with the accuracy of 1.6%. Also, it was found that the presence of carbon nanotubes inside the evaporator of the heat pipes can promote the nucleate boiling mechanism which in turn increased the TE of the solar collector. Also, the optimum filling ratio value and the installation angle were identified which were 0.6 and 55°, respectively. This was ascribed to a trade-off trend identified between the exist region inside the thermosyphon heat pipe and the amount of the vapor transported between the condenser and evaporator units, and also a trade-off between the residence time of the carrying fluid and the gravity effect, respectively.
117 citations
TL;DR: In this article, the authors present a numerical investigation of a hybrid photovoltaic-thermoelectric system with and without a flat plate heat pipe, which is a passive cooling device capable of effectively reducing the solar cell temperature.
113 citations
TL;DR: In this article, the authors focus on the systems that use a combination of phase change materials (PCM) and heat pipes to enhance thermal performance and efficiencies, and report that overall efficiency, heat storage and release rate of PCM is reported to greatly improve by the integration of heat pipe.
Abstract: Phase change materials (PCMs) have huge potential for latent thermal energy storage, waste heat recovery, heating, and cooling systems, due to their excellent thermal storage properties. However, the low thermal conductivity is most significant problem related with the PCMs, which retards the heat transfer rate and limits their practical applications. Heat pipe (HP) is extensively used heat transferring device, due to their ability to transfer heat isothermally over small and large distances. This review focuses on the systems that use a combination of PCM and heat pipes to enhance thermal performance and efficiencies. Overall efficiency, heat storage and release rate of PCM is reported to greatly improve by the integration of HP. These hybrid systems also have shown to overwhelm the issues such as low thermal conductivity of PCM and overheating of heat pipes.
TL;DR: In this article, an experimental investigation was conducted to quantify the heat transfer coefficient, thermal resistance and the thermal performance of a thermosyphon heat pipe charged with zirconia-acetone nanofluid.
TL;DR: In this paper, a thermal management system equipped with micro heat pipe array (MHPA) is designed to predict the transient temperature distribution of a battery pack based on MHPA cooling.
TL;DR: In this paper, a numerical analysis of the energy efficiency for a novel solar PVT Loop Heat Pipe (PVT-LHP) employing a novel Micro-channel evaporator and a novel PCM heat storage exchanger is presented.
TL;DR: In this paper, a biporous spiral woven mesh wick was developed to enhance the thermal performance of an ultra-thin flattened heat pipe for cooling high heat flux electronic devices, and the working fluid flow characteristics of the wick were analyzed theoretically.
TL;DR: In this paper, a three dimensional battery module model, including conjugated heat transfer sub-model, multi-cell sub-models and heat pipe submodel for a serially connected battery module using heat pipe cooling, is developed and experimentally validated.
TL;DR: In this paper, the proposed strategies to improve the thermal efficiency of different industrial, domestic, and innovative heat pipe solar collectors (HPSCs) are summarized and discussed. But, to the best of our knowledge, a comprehensive review which surveys and provides an overview of the studies undertaken to improve thermal performance of HPS systems by implementing different strategies has not been published to date.
TL;DR: In this paper, a micro pulsating heat pipe (MPHP) with five turns was fabricated by engraving an interconnected micro-channel on a 1.1mm thick transparent glass wafer.
TL;DR: In this article, the performance of a heat pipe solar water heating system to meet a real residential hot water consumption pattern theoretically and experimentally under non-ideal climatic conditions during a cold day in Perth, Western Australia was evaluated.
TL;DR: A state-of-the-art review on different types of heat pipe s, nanofluids preparation and characterization techniques have been carried out to satisfy the need of enhanced heat transfer and miniaturization in size.
TL;DR: In this article, an active air-cooling module based on a 1-mm-thick ultrathin miniature loop heat pipe with a flat evaporator for high-end ultra-slim laptop computers is presented and studied.
TL;DR: In this paper, the performance of functionalized multi-walled carbon nanotubes/water nanofluids was investigated in a novel type of thermosyphon which was made of an evaporator with square frustum shape, and a condenser composed of two connected tubes.
TL;DR: Numerical results show that the electric motor temperature is maintained at approximately the target value of 70 °C and up to approximately 370 kJ of energy is saved as compared to a conventional liquid cooling system for a specific 85 kW e-motor within 1500 s run time.
Abstract: Hybrid electric vehicle motors offer propulsion while accelerating and charge the battery pack when braking or decelerating. Though electric motors have high operating efficiency, considerable heat is generated based on required operating torque and speed. Thus, an efficient motor cooling system is needed to maintain the temperature within a prescribed range. The traditional motor liquid cooling system is effective but consumes energy to run the coolant pump and radiator fan. This paper examines the performance of a hybrid cooling system, combining heat pipes with conventional liquid cooling in a compact thermal cradle. This innovative design allows heat removal via an integrated thermal pathway by regulating various actuators (e.g., centrifugal fans, radiator pump, and fan) to minimize energy consumption. A reduced order thermal model predicts the motor's internal temperatures. Cooling performance is evaluated based on the Urban Assault driving cycle for different conditions. Numerical results show that the electric motor temperature is maintained at approximately the target value of 70 °C. Additionally, up to approximately 370 kJ of energy is saved as compared to a conventional liquid cooling system for a specific 85 kW e-motor within 1500 s run time.
TL;DR: In this article, a neural network was used to predict the heat transfer coefficient and the heat conductivity resistance equation for a heat pipe heat exchanger, and the results showed that the network with an accuracy of 0.9938 was able to accurately evaluate the results obtained in this study.
TL;DR: In this article, an experimental study was performed to assess the potential thermal application of a new nanofluid comprising carbon nanoparticles dispersed in acetone inside an evacuated tube solar thermal collector.
Abstract: In this article, an experimental study was performed to assess the potential thermal application of a new nanofluid comprising carbon nanoparticles dispersed in acetone inside an evacuated tube solar thermal collector. The effect of various parameters including the circulating volumetric flow of the collector, mass fraction of the nanoparticles, the solar irradiance, the tilt angle and the filling ratio values of the heat pipes on the thermal performance of the solar collector was investigated. It was found that with an increase in the flow rate of the working fluid within the system, the thermal efficiency of the system was improved. Additionally, the highest thermal performance and the highest temperature difference between the inlet and the outlet ports of the collector were achieved for the nanofluid at wt. % = 0.1. The best tilt angle and the filling ratio values of the collector were 30° and 60% and the maximum thermal efficiency of the collector was 91% for a nanofluid at wt. % = 0.1 and flow rate of 3 L/min.
TL;DR: In this article, the thermal performance of a novel solar collector integrated with stearic acid as phase change material has been investigated, where the solar radiation was collected by heat pipe equipped evacuated tubes and then stored in manifold integrated with phase change materials.
TL;DR: In this paper, a proof-of-concept plug-in oscillating heat pipe (OHP) with flat-plate evaporator and tube condenser has been developed and experimentally tested for the potential applications in EV battery thermal management.
TL;DR: In this paper, the performance of a new type of latent heat thermal energy storage (LHTS) device based on flat micro-heat pipe arrays (FMHPAs) with longitudinal rectangular fins is numerically studied by enthalpy-porosity technique based on finite volume method (FVM).
TL;DR: In this article, a micro-scale flat plate heat pipe with superhydrophilicity in a specially treated wick was explored and a visual study on the two-phase flow pattern was conducted.
TL;DR: In this paper, the authors provide sufficient knowledge on two-phase heat transfer in TPCTs to facilitate the nucleate pool boiling heat transfer coefficient calculations for thermosyphon users.
Abstract: With the objective of estimating the pool boiling resistance of two-phase closed thermosyphons (TPCTs), the work presented gives the state of the art of nucleate pool boiling correlations. A deep analysis of up-to-date equations reported for bubbles and nucleate boiling is carried out and recommendations are provided to select the most suitable and reliable mathematical models. After introducing the operation of thermosyphons, a section dedicated to bubbles provides basic knowledge on nucleation processes and bubble growth. The main boiling mechanisms occurring in thermosyphons with a filling ratio of 100%, i.e. pool boiling, are explained in a comprehensive way. The current state of the art of correlations predicting the number of active nucleation sites, the bubble departure diameters and bubble departure frequencies is presented. In addition, 27 correlations of nucleate pool boiling heat transfer coefficients are critically reviewed. For all sections, the advised correlations are reported in a clear and simple way using tables. The aim of this paper is to provide sufficient knowledge on two-phase heat transfer in TPCTs to facilitate the nucleate pool boiling heat transfer coefficient calculations for thermosyphon users. This paper can be taken as a starting point in the study of pool boiling in thermosyphons and heat pipes.