Three different types of nano particles tic, mgo and ag individually at different volume concentrations of 0. Heat exchangers selection, rating, and thermal design. Thermal properties of nanofluids containing nanosized particles in the working fluid are superior to base fluid. The heat exchanger must be isolated from system vibrations using flexible piping connections and isolation pads on the mounting feet. The rapid developments of secondary flow enhancing heat transfer due to increase in thermal conductivity of nanofluids when. Thermal performance and pressure drop of the helicalcoil heat exchangers with and without helically crimped fins. Whether youve loved the book or not, if you give your honest and detailed thoughts then people will find new books that are right for them. Effectiveness enchancement of heat exchanger by using. The effective properties of nanofluids like density, specific heat, thermal conductivity, and viscosity are to be calculated according to the mixing theory 3. Nanofluids represent potential substitute of conventional coolants in engine cooling system. Apr 06, 2014 nanofluids are a new class of advanced heattransfer fluids engineered by dispersing nanoparticles smaller than 100 nm in diameter in conventional heat transfer fluids. The objective of this paper is to develop a model for the analysis of compact heat exchangers and implement it in a code for the selection of this type of heat exchanger in airconditioning and refrigeration system design. Here, we will cite only those that are immediately useful for design in shell and tube heat exchangers with sensible heat transfer on the shellside. A compact heat exchanger is generally defined as one which incorporates a heat transfer surface having a high area density.
A computational fluid dynamics model for simulation of a thermosyphon with twophase flow including phase change heat transfer was developed. Temperature dependence of thermal conductivity enhancement for nanofluids. Similar to the plate heat exchanger, the shellandtube heat exchanger also shows augmentation and degradation in heat transfer performances of nanofluids. In contrast to the parallel flow heat exchanger, the counter flow heat exchanger can have the hottest coldfluid temperature greater than the coldest hotfluid temperatue.
Cfd analysis on heat and flow characteristics of double. Nanofluids are the new generation heat transfer fluids for various industrial and automotive applications because of their excellent thermal performance and the word was. The basic design equation and overall heat transfer coefficient the basic heat exchanger equations applicable to shell and tube exchangers were developed in chapter 1. Condenser heat exchanger thermal analysis and design. Therefore, the idea of utilizing nanofluids, whose thermophysical properties are better than. Heat transfer analysis of compact heat exchangers using standard curves. The effect of the nano fluids on compact heat exchanger is analyzed by using 6 ntu rating. Review on heat transfer enhancement using nanofluids in heat.
The results showed that the pressure drop of 4% nanoparticles of al 2 o 3 is almost double of the base fluid. The author found that the effectiveness of the heat exchanger increased from 74. Nanoparticles can be produced from several processes such as gas condensation, mechanical attrition or chemical precipitation techniques. Design and performance analysis of louvered fin automotive. A number of studies have focused on making the plate heat exchangers more efficient and compact, since energy usage increases day by day. The coolant circuit is usually pressurized using pressure cap to increase the boiling point of the coolant in many applications, which allows higher operating temperatures. Counter flow heat exchanger, nanofluids, iron powder, exchanger efficiency. The design parameters of the ceramic heat exchanger was considered from the paper a theoretical analysis and cfd simulation on the ceramic monolith heat exchanger by young hwan yoon. Counter flow heat exchangers are the most efficient of the three types.
The cuwater nanofluids are produced by using a onestep method, namely electroexploded wire technique, with four nanoparticles weight fractions i. The second law analysis allows the heat exchanger designer to consider both the factors simultaneously as the same is not possible with first law analysis. Heat transfer analysis of shell and tube heat exchanger using. The manufacturing cycle for the heat exchanger was reduced from months to weeks. In this paper a cooling circuit is modelled in trnsys version 17 and investigated in transient regime. The thermophysical properties of all types of nanofluids as coolants with a particle volume fraction of 2% and air are listed in tables 2 and 3, respectively. The literature survey gave an idea for approaching this. A detailed study of the parametric studies on compact heat exchanger is done by using entu numerical method and using al 2 o 3. Compact heat exchanger the ratio of the heat transfer surface area of a heat exchanger to its volume is called the area density a heat exchanger with. International journal of heat and mass transfer 78, 860870 online publication date. Fem and cfd approach brings new concepts of design data generation numerically which is more cost effective than generic design data and can be used by design and practicing engineers more effectively. They are widely used in various applications in thermal fluid systems including automotive thermal fluid systems such as radiators for engine cooling systems. With the help of nanofluids, the heat transfer rate increase. Use of nanoparticles in water based nanofluid as coolant in shell and tube heat exchanger.
Heat transfer analysis of helical coil heat exchanger with al2o3 nano fluid abstract the present study has focused on the use of helical coil heat exchangers hches with al2o3 water phase change material to understand if hches can yield greater rates of heat transfer. Deionized water and cuowater nanofluid were used as working fluids in the thermosyphon. Theresults indicate that al2o3water gave better heat transfer performance than water alone. They observed a significant increase in thermal conductivity of nanofluid. Experimental investigation of thermal and hydraulic. Uncertainty analysis of heatexchanger thermal designs.
Micronano heat transfer explores the thermal design fundamentals for microscale heat exchangers and the enhancement heat transfer for applications to heat exchanger design with nanofluids. For all types of nanofluids, the density, thermal conductivity, and dynamic viscosity appear significantly higher, while the specific heat of nanofluids is lower. Nanofluids are a new class of advanced heattransfer fluids engineered by dispersing nanoparticles smaller than 100 nm in diameter in conventional heat transfer fluids. Chapter 5 compact heat exchnager analysis using nanofluids. In this analysis, the heat transfer and pressure drop of a double helically coiled tube heat exchanger handling mwcntwater nanofluids have been studied with cfd software package. Ntu rating method using al 2 o 3 water nanofluid as coolant. Compact heat exchanger analysis, design and optimization. Exergy efficiency analysis of a shell and tube heat exchanger condenser based on its different. A plate heat exchanger consists of a series of thin and corrugated plates. Thermal design analysis of compact heat exchanger using nanofluids thermal design analysis of compact heat exchanger using nanofluids vasu, v. How to analyze heat transfer of compact heat exchangers. Thermal performance of platefin heat exchanger using. This experimental study investigates the effects of vortexgenerator vg and cuwater nanofluid flow on performance of platefin heat exchangers. Initially, hot and cold water are used to check the simulation and recorded the pressure and temperature of mwcntwater of nanofluids at 0.
Application of nanofluids in thermal design 77 coolant inlet tank, outlet tank, pressure cap and core. The design of shell and tube heat exchanger using kern method for water and steam combination is validated by wellknown dittusboelter equation of turbulent flow inside tube. The heat exchanger represents a car radiator in the circuit. Also presented in chapter 5 are singlephase forced convection correlations and flow friction factors for microchannel flows for heat transfer and pumping power calculations. A comprehensive source of generalized design data for most widely used fin surfaces in ches. Application of nanofluids in thermal design 79 where. Thermal design analysis of compact heat exchanger using nanofluids. Theoretical analysis of compact heat exchanger using. Analysis and cfd simulation on the ceramic monolith heat exchanger by young hwan yoon. Numerical study of fluid dynamic and heat transfer in a compact heat exchanger using nanofluids, isrn mechanical engineering, vol. Jan 01, 2008 thermal design analysis of compact heat exchanger using nanofluids thermal design analysis of compact heat exchanger using nanofluids vasu, v. Design and analysis of hair pin heat exchanger using tic. T, then the expression for the lmtd reduces simply to. Experimental runs wereconducted which include the runs for water, 40 nm al2o3water and 100 nm al2o3water.
First, the simulation results for the two fins, offset strip and wavy, are validated with. Results show that, maximum heat flux of the nanofluid is about 46 % higher than that of water. The report is about the design of a condenser for 100 cubic meter cool room at 3 degrees celsius and r4a. This project increased my thinking and understanding capability and after the completion of this project, i experience the feeling of achievement and satisfaction. The purpose of this research is to investigate the thermal and hydraulic characteristics of nanofluid in turbulent flow regime in a plate heat exchanger with a sine pattern in which cold and hot flows alternately pass through the plates.
The presentation and discussion of a case study on the performance of the heat exchanger on the 500 kw orc system is presented as follows. The heat transfer analysis is done by considering water inside the tube and steam on shell side. Create finite volume mesh for 3d model of ceramic heat exchanger by using ansys icem cfd software and import into ansys fluent software. Condensers which have a coolant and a condensing vapor brought into direct contact and other types which have the coolant and a condensate stream separated by a tube wall or a solid surface. Working fluids with different prandtl numbers, air, water, oil, and ethylene glycol are considered as coolants. Analysis of heat transfer enhancement of heat exchanger. Thermal evaluation of nanofluids in heat exchangers. The heat transfer rate uncertainty analysis of heatexchanger thermal designs 865 and area may be expressed, respectively, as q ua ar, al atatj, a2 where u is the overall heat transfer coefficient and atm the meantemperature difference. This article concentrates on compact heat exchangers and how to use standard curves for heat transfer analysis. Vasu related information 1 department of mechanical engineering, national institute of technology, warangal 506 021, india. A model for the analysis of compact heat exchangers. Heat transfer enhancement by using zno water nanofluid in. Analytical investigation of exergetic analysis of louvered.
A heat exchanger is a device that is used to transfer thermal energy enthalpy between two or more fluids, between a solid surface and. Thermal performance of a micro heat exchanger mhe working. Apr 17, 2019 an experimental investigation was performed with the view to assess the heat transfer characteristics of a waterbased nanofluid in a micro heat exchanger employed to quench a high heat flux heater for industrial and microelectronic cooling applications. Other readers will always be interested in your opinion of the books youve read. Fins attached to it enhance heat transfer from the hot coolant to the outside air. Heat transfer of aluminiumoxide nanofluids in a compact heat. Here, we give the fundamental equations for the design and analysis of heat exchangers. Thermal analysis of double pipe heat exchanger by changing. Gasketed plate heat exchangers phes occupy a crucial position in the energy sector due to their efficient and compact design.
A condenser is a kind of heat exchanger in which vapors are changed into liquid state by removing the latent heat with the aid of a coolant like water. They also investigated the effectiveness of the heat exchanger. Application of nanofluids in thermal design of compact heat. We design heat exchangers for new and retrofit process applications. It also examines singlephase forced convection correlations as well as flow friction factors for microchannel flows for heat transfer and pumping power. The density of nanofluid is calculated using pak and cho correlations 7. The ultimate aim of this report is to design an air cooled heat exchanger, preferably of shell and tube type, that can be used to transfer the heat energy generated in the windings of 3phase induction motor working at 800 rpm assumed. Here, the second method has been explored by using nanofluids as one of the participating fluids in the heat exchanger. Compact heat exchangers are a class of heat exchangers, which features at least one of the fluids, on one side, as a gas. Their thermophysical measurements of the nanofluid cuo in water, 4 vol% reveal that the increase in thermal conductivity is accompanied by a significant drop in heat capacity and an increase in viscosity. The inset figure shows the openedup heat exchanger, revealing the inside flow tubes. Experimental investigation of pipe in pipe tube heat.
Compact heat exchangers ches are characterized by a high surface area per unit volume, which can result in a higher efficiency than conventional heat exchangers. Objectives by the end of the course you will be familiar with the main exchanger types know which is likely to be the best type for a given application understand what are the key factors in exchanger design be able to estimate the. Analysis of thermal performance of a car radiator employing. We can also evaluate the thermal performance of existing heat exchangers for process optimization, process or equipment modifications or change of service. Thermal conductivity of nanoparticle fluid mixture.
Coolant tanks are positioned either on top and bottom of the core. Thermal design analysis of compact heat exchanger using nanofluids v. The inner pipe is a suction pipe of the pump in which hot hydrocarbon flows and in outer annulus cold crude oil passes from opposite direction. Kleinstreuer 2004 a new thermal conductivity model for nanofluids, journal nano particle research, vol. Review of literature on heat transfer enhancement in heat. Thermal design of heat exchangers, thermal engineering.
The circuit is composed by a heating system, a pump and a heat exchanger. Modeling of ceramic heat exchanger by using nxcad software. It has enriched my life, giving me an opportunity to work in a new environment of cryogenic heat transfer. Condenser heat exchanger is very common in process industry, condensers may be classified in two main types. Thermal design analysis of compact heat exchanger using. A 3d printed millistructured heat exchanger made from stainless steel with a gyroid design. Five different concentrations of nanofluids in the range of 0. In this case, our main concern is to have a robust model for the analysis of compact heat exchangers working as condensers and. This software deals with the type where the streams are separated. In the conventional heat exchangers, pipes are larger in size which makes heat exchanger bulky. Compact heat exchnager analysis using nanofluids the thermal analysis of compact heat exchanger 9 is done by considering the fluid outlet temperatures or heat transfer rate as dependent variables, and is related to independent parameters as follows h o. If the heat exchanger is located at the inlet or discharge of a blower with a pulsating flow, such as a roots type rotary lobe blower, the heat exchanger must be protected from the pulsation by a chambered silencer. The test rig was setup to represent the actualapplication of the nanofluids in cooling of a compact heat exchanger.
Effectiveness enchancement of heat exchanger by using nanofluids. Design and analysis of hair pin heat exchanger using tic, mgo. The heat recovery from hot fluid is used to increase the temperature of cold fluid. A heat exchanger is a device that is used to transfer thermal energy enthalpy between two or more fluids, between a solid surface and a fluid, or between solid particulates and a fluid, at different temperatures and in thermal contact. Therefore, the idea of utilizing nanofluids, whose thermophysical properties are better than those of industrial fluids, have. Modeling the effective thermal conductivity of nanofluids using full factorial design analysis. Following figure details the boundary conditions for the heat exchanger. Also by increasing the nanofluid concentration, the wall temperature. In this study, the performance of a plate heat exchanger phx, with chevron. Application of nanofluids in thermal design of compact. The cold water based nanofluids flow in tube side and water as hot fluid flows on shell side. Jul 17, 2019 gasketed plate heat exchangers phes occupy a crucial position in the energy sector due to their efficient and compact design.
Introduction car radiator, one example of compact heat exchanger, is an important part in automotive cooling system. Recent development of nanotechnology brings out a new heat transfer. Numerical study of fluid dynamic and heat transfer in a. Effect of nanofluids on heat transfer enhancement in. Thermophysical properties of nanofluids and nanofluids model. Comparative appraisal of five common fin configurations plain, perforated, offset strip, wavy, and pin on the operation of the platefin heat exchanger is the main purpose of this study.
600 1218 1549 1414 1232 750 1344 555 559 434 289 1188 817 1390 74 751 1100 667 385 1103 1178 318 1374 398 852 755 72 1237 1557 35 1326 881 1163 1118 230 746 154 97 1266 432 272 984 978 25 438 663 750