Experimental Analysis of Heat Exchanger and Simulation of Result Using Solid Works Software

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1 Experimental Analysis of Heat Exchanger and Simulation of Result Using Solid Works Software Mukul Sangwan 1, Manpreet Singh 2 1 Student Department of Mechanical Engineering, RIEM College Rohtak, Haryana 2 Assistant Professor Department of Mechanical engineering RIEM College Rohtak, Haryana ABSTRACT Heat exchangers one of the most important heat and mass transfer apparatus in industries like electric power generation, oil refining and chemical engineering etc. are designed with preciseness for optimum performance and long service life. Shell and Tube heat exchangers are having special importance in boilers, oil coolers, condensers, pre-heaters. They are also widely used in process applications as well as the refrigeration and air conditioning industry. The robustness and medium weighted shape of Shell and Tube heat exchangers make them well suited for high pressure operations. The basic configuration of shell and tube heat exchangers, the thermal analysis and design of such exchangers form an included part of the mechanical, thermal, chemical engineering scholars for their curriculum and research activity. Here we analyses counter flow and parallel flow heat exchanger by experimentally and analytical by using solid works software. By using Solid works we find the all the data result for parallel and counter-flow. This also consist of experimental data of counter flow and parallel flow heat exchanger and simulate the over data on software using solid works. Simulation gives different flow of trajectory and flow of heat from hot and cold water. This method used in design of heat exchanger with a baffle cut of 25%. All the procedure have done to find which flow have better, counter-flow or parallel flow and what are the safe design of a heat exchanger. The result obtained from this shows us that the desired properties from a heat exchanger i.e. overall heat transfer coefficient, shear stress, heat flux, and other factors which are helpful for the design of heat exchanger. In both results we find the difference between the experimental value and the analytical value of overall heat transfer coefficient value. The difference is found due to fouling factor, cavitations and design of heat exchanger. Keywords: double pipe heat exchanger, rib, enhanced heat transfer, artificial roughening, annular flow. INTRODUCTION First is the question is rise what is the heat exchanger? Heat exchanger is nothing but a device which is used to transfer the heat from one medium to another medium. The heat transfer medium may be fluids, gases and other medium. Heat is exchange between two fluids due to temperature difference. Heat exchangers are used in various filed such as industry, power plant, nuclear reactor, in domestic. Heat exchanger is used in space heating, air-conditioning, waste heat recovery and chemical processing. In heat exchanger heat is transfer due to convection process on the each side of fluid and the conduction through the wall of the heat exchanger which is separates the fluid. Therefore, we have to analysis of overall heat transfer coefficient and logarithmic mean temperature difference. Heat exchanger is also help to find the effectiveness of the device. A typical or best example of a heat exchanger is found in the internal combustion engine. In which hot fluid is circulating through the radiator and the air flows pass through the coils. This cools the coolant and the heat is transfer in the incoming air. For better efficiency heat exchanger are designed to maximize the surface area of the wall between the two fluids and minimize resistance to the fluid flow through the heat exchanger. The exchanger s performance can also be affected by the addition of fins in both directions. Which increase the surface area and the increase the fluid flow and decrease turbulence? And the temperature across the heat transfer varies with position, and it can be find with mean temperature. 1

2 Plate heat exchanger Fig 1: Heat exchanger This is another type of heat exchanger. This type of heat exchanger consists of composed of multiple, thin and slightly separated plates. They have lager surface areas and fluid flow passages for heat transfer. This type of arrangement can be more effective than the shell and tube heat exchanger. Now advances technology gasket and brazing have made the plate type heat exchanger increasing their practical. In HVAC, application large heat exchanger of this type are called plate and frame; which is used for open loops,these heat exchanger are normally of the gasket type. Because there ease to disassembly, cleaning and inspection. There are many types of permanently bonded plate heat exchanger such as dip brazed, vacuum brazed and welded plate varieties. Some plates have stamped with chevron, dimpled or others patterns, where others may have machined fins and grooves. Fig 2: simple plate heat exchanger LITERATURE REVIEW Z.H. Ayub, 2003: In this paper, he presented the new correlations for evaporation heat transfer coefficient and friction factor for heat transfer and pressure drop correlations for refrigerant evaporators, which are applicable to various system pressure conditions and plate chevron angles. Plate heat exchangers are used regularly in the heating, ventilating air conditioning, and refrigeration industry. Here the correlations are based on actual field data collected during several years of installation and operation of chillers, and they are intended to serve as design tools and perhaps as a starting point for future research. Impact factor found in that research is Martin Sievers, John H., 2013: In this paper, they examined flat plate heat exchangers for use as dehumidifiers in humidification-dehumidification (HDH) desalination system. The temperature and humidity ratio differences that drive mass transfer are considerably higher than in air-conditioning system, making current air-conditioning dehumidifier designs and design software ill-suited to HDH desalination applications. In this work a numerical 2

3 dehumidifier model is developed and validated against experimental data. The model uses a logarithmic mass transfer driving force and an accurate Lewis number. The heat exchanger is subdivided into many cells for high accuracy. The Ackermann correction takes into account the effect of non-condensable gases on heat transfer during condensation. The influence of various heat exchanger design parameters is thoroughly investigated and suitable geometries are identified. Among others, the relationship between heat flow, pressure drop, and heat transfer area is shown. The thermal resistance of the condensate layer is negligible for the investigated geometries and operating point. A particle embedded polymers as a flat plate heat exchanger material for seawater operation substantially improves the heat flux relative to pure polymers and approaches the performance of titanium alloys. Thus, the use of particle-embedded polymers is recommended. The dehumidifier model can be applied in design and optimization of HDH desalination system. ZahidAyub, M. Sultan Khan, Tariq S. Khan, 2013: In this paper, they presented the use of carbon dioxide and ammonia in low temperature cascade systems is gaining momentum in the industrial refrigeration market. And the use of heat exchanger as cascade condenser is a viable option due to the high thermal efficiency and smaller footprint characteristics of such exchangers. This article presents the latest research on condensation of carbon dioxide and evaporation of ammonia in various corrugated plate exchangers at different saturation temperature and heat/mass flux. The data are reduced to generalized empirical correlations to be used as design tools by engineers. It also discusses the mechanical aspects of plate exchangers and their suitability in cascade systems. H.H. Al-Kayiem& L. Al-Habeeb, 2014: In this paper, ribbed double pipe heat exchanger is experimentally analysed. Convection heat transfer can be enhanced by imposed turbulence in the annular flow of a double pipe heat exchanger. This paper presents and discusses the results obtained from experimental measurement by the installation of turbulence promoters, having rib configuration, on the inner surface of the cold flow annulus of a counter flow double-pipe heat exchanger. The promoters have been selected with rib s height to hydraulic diameter, e/dh equal to and two pitch to height ratios, p/e equal to 10 and 15. The annular cold flow was investigated within Reynolds number range of 2000 to The measured data enabled us to estimate the friction factor, Reynolds number and Stanton number of each case in order to analyse the performance enhancement of the double pipe heat exchanger. The results showed that enhancement in the heat transfer, in terms of the Stanton number, was combined with a small penalty in the pressure drop, which was due to an increase in the friction factor values. Within the tested ranges of e/dh and Re, the performance index indicated enhancement of about 1.3 to 1.8 at pitch to p/e = 10. It is recommended to investigate more cases of rib s heights and installation in the hot fluid flow side. Cardone and Panelli, 2010: They experimentally investigated the effect of periodic patterns of protrusions (ribs) on the free-convection heat transfer in a vertical plate with uniform heat flux rate boundary condition. The result shows that the use of periodic pattern of ribs placed on a vertical flat plate in natural convection improves convective heat transfer to its maximum. The above literature survey shows that the numerous experimental and theoretical studies have been performed to enhance heat transfer in the channel flow and on electronic circuit board; however there is still a room to discuss. M.V. Ghori and R.K. Kirar, 2012: They both work on the three dimensional CFD simulations are work to carried out to heat transfer and fluid flow characteristics of plain tube and fin heat exchanger using fluent software. They also find the pressure drop characteristics of the heat exchanger for Reynolds number ranging from 330 to Fluid flow and heat transfer are simulated and compare the result for both the flow such as laminar and turbulent. The fluent software has been sufficient for simulating the flow in tube fin heat exchangers. Usman U.R. Rehman, 2011: They work on the shell and tube heat exchanger using the un-baffled for the experiment. They work on the pressure drop and the heat transfer coefficient by the numerical modelling. All the flow rate and temperature inside the shell and tube are considered by the CFD software which is generated automatically by the software. The simulations are performed on the single shell and tube and that data is compared by the experimental data. It is used the k-w sst model for the getting the better result at the low Reynolds no. because the k-w sst model gives the batter result as compared to the other model. Yongmann M. Chung and Paul G. Tucker, 2004: In this paper, they numerically studied the unsteady heat transfer enhancements in grooved channel and sharp 180 bend flows, especially relevant to electronic systems. Prior to above to find the most efficient numerical approaches, performances of various pressure corrections, convective and temporal schemes were studied. 3

4 Kamal K. Sikka, Kenneth E. Torrance, 2002: They investigated the effects on heat transfer by geometrically rearranging the surface area of a finned heat sink. Novel heat sinks with fluted and wavy plate fin configurations were designed and fabricated together with conventional longitudinal-plate and pin fin heat sinks. The thermal performance of the novel and conventional heat sinks was measured and compared for the horizontal and vertical base plate orientations under natural and low-velocity forced convection conditions. OBJECTIVE & PROBLEM FORMULATION Heat exchanger is widely used in variety of industries like oil refineries, nuclear power plants and other manufacturing industries. In industries, it is used for heating and cooling of water, oil and gas. Almost 60% industries uses shell and tube heat exchanger. So a wide investigation has been carried out in the field of shell and tube heat exchanger by taking different-different parameters like tube diameter, length of tube, no. of tube, no. of baffles, no. of passes and material by which tube is made. Shell and tube heat exchangers are used for high pressure applications. This is because the shell and tube heat exchangers are robust due to their shape. To designing shell and tube heat exchanger several thermal design features must be considered. There can be many variations on the shell and tube design. Typically, the ends of each tube are connected to plenums through holes in tube-sheets. The tube may be straight or bent in the shape of a U, called U-tubes. To design heat exchanger following parameters are considered:- Tube Diameter:- Using a small tube diameter makes the heat exchanger both economical and compact. However, it is more likely for heat exchanger to foul up faster and the small size makes mechanical cleaning of the fouling difficult. To prevail over the fouling and cleaning problems, larger tube diameters can be used for better design of heat exchanger. And to determine the tube diameter, the available space, cost and fouling nature of the fluid must be considered. Tube Thickness:- Thickness of wall tube is usually determined to ensure that there is enough room for corrosion and the flow induced vibration has resistance and axial strength, availability of spare parts, hoop strength and buckling strength. Tube Pitch:- When designing the tubes, it is practical to ensure that the tube pitch is not less than 1.25 times the tube s outside diameter. A larger tube pitch leads to a larger overall shell diameter, which leads a more expensive heat exchanger. Baffle Design:- Baffles are used to direct fluid across the tube bundle. They run perpendicularly to the tube from sagging over a long length. They can also prevent the tubes from vibrating. The most common type of baffle is the segmental baffle. The semicircular segmental baffles are oriented at 180 degrees to the adjacent baffles forcing the fluid to flow upward and downwards between the tube bundle. These parameter play an important role when designing a heat exchanger. There are various other parameters which always kept in mind when designing any heat exchanger. First, these are the design that is used in these tube and shell heat exchanger is very compact and reliable. Second, the design is capable to handle high pressure and temperature. Third, heat exchanger can be used in system that operate in high temperature and pressure and the fouling factor is also considered before designing a heat exchanger. Everyday there are many research have been done on heat exchanger by changing tube material, by changing no. of passes, thickness and diameter of tube. There are also investigated different-different types of heat exchangers experimentally and after that their results are optimized and simulated by different-different methods and softwares like taguchi s methods, Solid works, Fluent, CFD and Matlab etc. These all are used to improve the design of heat exchanger and its effectiveness. Now to improve design of heat exchanger and its effectiveness, we also study experimentally shell and tube heat exchanger in parallel and counter-flow and simulated the result using solid works software by taking differentdifferent parameter. Literature review shows that many experimental and theoretical attempts have been made to heat transfer enhancement in laminar separated flows and various attempts have been made in study of forced convection and plate finned heat exchangers. No attempts so far has been made to experimental analysis of heat exchanger and simulation of result using solid works. So First to prepare the step of the heat exchanger in the HT lab. After that we run the experiment and find the experimental values. Then find the overall heat transfer coefficient, LMTD values for the heat exchanger. After that we compare the standard value of the overall heat transfer coefficient and the LMTD values. 4

5 After that we find the problem which are found during the comparing the values with the standard values. We try to improve the design of the heat exchanger. We applied all the experimental values on the solid works software. Which is a 3D CAD software. We used the different parameters such as no. of tubes, shell diameter, no of passes, and mass flow rate. After applying all the changes during the simulation we got the nearly accurate value of the standard value of the heat exchanger. After all the changes are calculated and improve the heat exchanger design. We also find the heat flow and flow trajectories on the basis of the experimental data. These also help which dimensions are gives the best result. Easy to simulate the data and get the best result for the heat exchanger. And also using the different software such as CFD, FLUENT software, solid works for the find the velocity profile and the temperature profile. CONCLUSION From the experimentally investigation, we find different-different graphs which shows the comparison between parallel and counter-flow heat exchanger and also show which type of heat exchanger is more useful in industries. From the fig. 15, we find that at point 1, mean temperature efficiency of parallel and counter-flow are nearly equal and at point 2 and 3, counter-flow have higher mean temperature efficiency than parallel flow and at point 5, both parallel and counter-flow have nearly equal mean temperature efficiency. And from fig. 16, at point 1, parallel flow has higher LMTD than counter-flow and at point 2, counter-flow have higher mean temperature efficiency than parallel flow. After that at point 3 and 4, both have nearly same mean temperature efficiency and at point 5, counter-flow is slightly greater than parallel flow. Above conclusion show that counter flow is better than parallel flow because the temperature difference in the counter-flow is higher than parallel flow. And by Solid works software on both parallel and counter-flow conditions, we easily found all the data result. For counter-flow, heat transfer coefficient is W/m².K and max shear stress is.006 Pa. and for parallel flow, heat transfer coefficient is W/m².K and shear stress is.007 Pa. So from the above result, we can easily say that counter-flow is better than parallel flow because counter- flow have higher heat transfer rate than parallel flow. We also found the value of overall heat transfer coefficient, shear stress, heat flux, and the other factors which are very helpful for the design of heat exchanger. We found the difference between the experimental value and the analytical value of overall heat transfer coefficient also. These differences are found due to fouling factor, cavitations and design of the heat exchanger. REFRENCES [1]. Vijaya S. Gullapalli, Bengt Sunden(2014). CFD Simulation Of Heat Transfer And Pressure Drop In Compact Brazed Plate Heat Exchangers. Heat Transfer Engineering 35(4), [2]. E. Ekramian, S. Gh. Etemad, M. Haghshenasfard, (2014). Numerical Analysis of Heat Transfer Performance Of Flat Plate Solar Collectors. International Journal Of Heat And Mass Transfer, ISSN: , Volume 1, Pages [3]. Naiem Akhtar, S. C. Mullick,(2012). Effect Of Absorption Of Solar Radiation In Glass-Cover(S) On Heat Transfer Coefficients In Upward Heat Flow In Single And Double Glazed Flat-Plate Collectors. International Journal Of Heat And Mass Transfer,Vol.55(1), [4]. Alice M. Stoll,(1967). Heat Transfer In Biotechnology Original Research. Advances In Heat Transfer, Volume 4, Pages [5]. Imanzahmatkesh, (2014). Natural Convection And Entropy Generation In A Porous Enclosure With Sinusoidal Temperature Variation On The Side Walls. International Journal Of Heat And Mass Transfer, Volume 1, Pages [6]. Durgesh Bhatt, Priyanka M. Javhar,(2012). Shell And Tube Heat Exchanger Performance Analysis. International Journal Of Science And Research, ISSN , Vol.3 Issue 9,Pages [7]. Swapnilahire, Purushottamshelke, Bhalchandrashinde, Nileshtotala,(2014). Fabrication And Analysis Of Counter Flow Helical Coil Heat Exchanger. International Journal Of Engineering Trends And Technology,ISSN , Volume 15, Number 5, Pages [8]. Dhananjay Kumar, Prof. Alokchoube,(2014). Experimental Study Of Heat Transfer Enhancement In Fin Tube Heat Exchanger By Vortex Generator. International Journal Of Engineering Sciences & Research Technology, ISSN ,Vol.3(5), Pages [9]. Prabhakar Ray, Dr. Pradeep Kumar Jhinge,(2014). Heat Transfer Rate Enhancements By Wire Coil Inserts In The Tube. International Journal Of Engineering Sciences & Research Technology, ISSN ,Vol.3(6), Pages [10]. Alberto Garcia, Pedro G. Vicente, Antonio Viedma. Experimental Study Of Heat Transfer Enhancement With Wire Coil Inserts In Laminar-Transition-Turbulent Regimes At Different Prandtl Numbers. International Journal Of Heat And Mass Transfer, 2005,48. Pages