Review of Experimental Analysis of Parallel and Counter Flow Heat Exchanger

Review of Experimental Analysis of Parallel and Counter Flow Heat Exchanger

Akshaykumar Magadum,

Aniket Pawar, Rushikesh Patil, Rohit Phadtare.

Abstract:-Performance of Parallel and Counter Flow Heat Exchanger considering temperature changes in water and lubricating oil (Synthetic oil) are to be studied. In this paper, we are going to study previous research paper and conclude with the results. By going through research paper we came to know that heat exchanger performance varies from fluid to fluid and temperature to temperature. Also we have calculated LMDT by varying flow rate and temperature of hot water and cold fluid. The performance of Parallel and Counter flow are compared. The performance of such heat exchangers under different operating conditions is also discussed.

Keywords:-Parallel flow, Counter flow, heat transfer coefficient, LMTD, effectiveness.

1. INTRODUCTION

   Heat exchangers are the devices in which heat is transferred from one fluid to another. Common examples of heat exchangers are radiator of motor car, Condenser at the back of a domestic refrigerator and Steam boiler of a Thermal power plant.

   Parallel Flow:-

   An arrangement of a heat exchanger where the hot and cold fluids enter at the same end and flow to the exit is known as Parallel Flow.

   Mr. T. C. Mestri

   Department of Mechanical Engineering, Sanjay Ghodawat Polytechnic, Atigre, India.

   Applications:-

   Cryogenics, in heating and air conditioning systems, in food industries, in chemical industries, in dairy industries, in petroleum industries, in nuclear power plant, in surface condenser in power plants.

2. LITERATURE REVIEW

   S. Pradeep Narayanan et al. [1] studied on Performance of a counter-flow heat exchanger with heat loss through the wall at the cold end.

   The performance of high effectiveness heat exchangers used in cryogenic systems is strongly controlled by irreversibility such as longitudinal heat conduction and heat leak from ambient. In all heat exchanger analyses, it is assumed that no heat is lost through the heat exchanger walls. In the case of small J-T refrigerators such as micro miniature refrigerators, the heat exchanger cold end is almost directly connected to the evaporator, which may result in a large amount of heat loss through the heat exchanger wall at the cold end. The rate of heat loss through the wall at the cold end is also strongly dependent on the longitudinal thermal resistance of the wall.

   In this paper, they present the relationship between the effectiveness of a heat exchanger losing heat at the cold end and other resistances such as number of transfer units (NTU), longitudinal thermal resistance etc. The performance of such heat exchangers under different operating conditions is also discussed.

   Counter Flow:-

   Fig 1.1

   Prabhat et al. [2] studied on a performance evaluation of counter flow heat exchanger considering for low temp application. He found those Counter flow heat exchangers are commonly used in cryogenic systems because of their high effectiveness. They observed that losses such longitudinal conduction through wall, heat in leak from surrounding, flow maldistribution etc. They extended their

   An arrangement of a heat exchanger where the hot and cold

   fluids enter at the opposite end and flow to the exit is known as Counter Flow.

   Fig 1.2

   study to understand quantitative effect of heat in leak and axial conduction parameters on degradation of heat exchanger performance for 300-80k and 80-20k temperature range.

   J. Kragh et al. [3] studied about New counter flow heat exchanger designed for ventilation systems in cold climates. The work of designing a high effective heat exchanger capable of continuously defrosting itself seems to be successful. Good accordance between the calculated and measured efficiency was found at dry condition. To minimize the energy cost, a more efficient way to solve the freezing problem is therefore desirable. In this paper, the construction and test measurements of a new counter flow

   heat exchanger designed for cold climates are presented. The developed heat exchanger is capable of continuously defrosting itself without using supplementary heating. Other advantages of the developed heat exchanger are low pressure loss, cheap materials and a simple construction. The disadvantage is that the exchanger is big compared with other heat exchangers.

   P.C. Mukeshkumar et al. [4] has discussed about the experimental study on parallel and counter flow configuration of a shell and helically coiled tube heat exchanger using Al2O3 / water nanofluid. This study was done by changing the parallel flow configuration into counter flow configuration under laminar flow regime. The Al2O3 / water nanofluid at 0.4% and 0.8% particle volume concentration were prepared by using two step methods. The overall heat transfer coefficient is 5-9% higher than that of parallel flow at 0.8% nanofluid.

   Mushtag I. Hasan et al. [5] studied about Investigation of a counter flow micro channel heat exchanger performance with using nanofluid as coolant. In this paper the performance of counter flow micro channel heat exchanger (CFMCHE) is numerically investigated with a Nano fluid as cooling medium. Two types of Nano-fluids are used a: Cu- water b: Al2O3. They found that nanofluid cooled CFMHE when the flow rate was low. For high flow ate the heat transfer was dominated by the volume flow rate and nanoparticles did not contribute to extra heat absorption. It means that, at high flow rate they found that the nanoparticles could not absorb more heat than water cooled counter flow heat exchanger.

   Swapnil et al. [6] has discussed about fabrication and analysis of counter flow helical coil heat exchanger. The heat transfer coefficient increases with increase in Reynolds no. as Nusselt no. increases. Greater will be the turbulence higher will be the heat exchange. As the Dean no.is increasing with increase in Reynolds no. so, the heat transfer rate will also increase with the Reynolds number.

   Christian et al. [7] has discussed about experimental Investigation on the Effect of Fluid Flow Rate on the Performance of a Parallel Flow Heat Exchanger. The effect of fluid flow rate on the performance of parallel flow heat exchangers in an extended plate with regard to thermal efficiency,overall heat transfer coefficient, convective heat transfer coefficient, flow rate, and Reynolds number. Physical characteristics and thermal performance of a real heat exchanger were studied in this work. Also the convective heat transfer coefficient increases with both Reynolds and Nusselt numbers, which increases the overall heat transfer coefficient.

   R. W. Tapre et al. [8] has discussed about Review on Heat Transfer in Spiral Heat Exchanger Energy saving is major matter in our global world, and heat exchanger is very useful for energy saving. Study on the various effects of feed flow rate and the coil diameter was done and

   concluded that on increasing the feed flow rate the pressure drop increases and vice versa. A relation between the pressure drop and the feed flow rate for the steady state Newtonian fluid into the Archimedean spiral tubes was developed.

3. EXPERIMENTAL SETUP Setup Specifications:-

   1. Digital Temp. Indicator: 2000C -1 No.

   2. Geyser for hot water

   3. Inner tube: I. D. 11mm

   4. Outer tube: O.D. 13mm.

   5. Length of the heat exchanger 1600 mm.

   6. Ball valves for flow arrangement.

   Fig. 1.3 Experimental Set up

4. PROPOSED WORK

   <>The apparatus is a conventional tube in tube type of heat exchanger. In this heat exchanger hot fluid flows through inner tube and cooling water flows through the annulus. The apparatus is mounted on a board & is provided with a system of pipes & valves. Parallel & Counter type of flow arrangement can be done by opening & closing of ball valves as per requirement. Hot fluid flows always in one direction & cold fluid flow direction can be changed from either parallel flow to counter flow or vice versa.

   Temperature Indicator along with selector switch is provided for measurement of temperature of hot fluid & cold fluid. An electric geyser is used to heat the water. Outer tube of the heat exchanger is provided with adequate insulation to minimize the heat the heat losses. Material used for the construction in G.I.

   The flow arrangement for parallel & counter flow is as shown in below fig. 1.1 & 1.2.

   Fig. 1.4 Parallel Flow

   Fig. 1.5 Counter Flow

5. CONCLUSION

   From the literature review of experimental investigation of performance of parallel & counter flow heat exchanger we came to the conclusion that:

   1. Heat transfer is more in case of counter flow heat exchanger using water or any other oil as heat carrying medium.

   2. Most of the research is done taking water as a working fluid both as heat carrying & heat absorbing medium.

   3. Heat transfer can be enhanced by changing the material of construction of pipes, taking liquid as a heat absorbing medium having high specific heat, changing mass flow rates.

6. REFERENCES

1. S. Pradeep Narayanan, G. Venkatarathnam. Performance of a counterflow heat exchanger with heat loss through the wall at the cold end, Elsevier Science Cryogenics 39 (1999) Page No. – 4352

2. Prabhat Gupta, M.D. Atrey. Performance evaluation of counter flow heat exchangers considering the effect of heat in leak and longitudinal conduction for low-temperature applications, Elsevier Science ,

   Cryogenics 40 (2000) Page No.- 469-474

3. J. Kragh, J. Rose, T.R. Nielsen, S. Svendsen. New counter flow heat exchanger designed for ventilation systems in cold climates, Elsevier Science Energy and Buildings 39 (2007) Page No.- 11511158

4. P.C. Mukeshkumar, J. Kuma, S. Suresh, K. Praveen babu. Experimental study on parallel and counter flow configuration of a shell and helically coiled tube heat exchanger using Al2O3 / water nanofluid, J. Mater.

   Environ. Sci., Volume-3, Issue-4, 2012, Page No.-766-775

5. Mushtaq I. Hasan, Abdul Muhsin A. Rageb, Mahmmod Yaghoubi. Investigation of a Counter Flow Micro-channel Heat Exchanger Performance with Using Nanofluid as a Coolant, Journal of Electronics Cooling and Thermal Control, volume-2, 2012, Page No.-35-43

6. Swapnil Ahire, Purushottam Shelke, Bhalchandra Shinde, Nilesh Totala. Fabrication and Analysis of Counter Flow Helical Coil Heat Exchanger, International Journal of Engineering Trends and Technology (IJETT)

   Volume 15 Number 5 Sep 2014 Page No.- 2231-5381

7. Christian O. Osueke, Anthony O. Onokwai Adeyinka O. Adeoye. Experimental Investigation on the Effect of Fluid Flow Rate on the Performance of a Parallel Flow Heat Exchanger, International Journal of Innovative Research in Advanced Engineering (IJIRAE) Issue 6, Volume 2 (June 2015) Page No. – 2349-2163

8. R. W. Tapre, Dr.Jayant P. Kaware. Review on Heat Transfer in Spiral Heat Exchanger, International Journal of Scientific and Research Publications, Volume 5, Issue 6, June 2015 Page No.- 2250-3153