Dry Testing Method for Heat Exchangers

Automotive engine produce extra heat during engine operation. Automotive engine cooling system regulates engine surface temperature for optimum efficiency. Recent advancement in engine for power forced engine cooling system to develop new strategies to improve its performance efficiency and to reduce fuel consumption along with controlling engine emission to mitigate environmental pollution norms. Automobile radiator test rig is designed to evaluate the performance of automobile radiator. The modeling of radiator has been described by two methods, one is finite difference method and the other is thermal resistance concept. In the performance evaluation, a radiator is installed into a test setup and the various parameters including mass flow rate of coolant, inlet coolant temperature etc. are varied. In the present analysis dilution level of thee coolant is varied and higher efficiency is attained. Thermal efficiency V/S change in temperature , Inlet temperature V/S thermal efficienc...

In this paper various methods for radiator performance evaluation and testing of the radiator are considered because all internal combustion engines produce heat as a byproduct of combustion and friction. This heat can reach temperatures up to 1925°C (3500°F) and can have catastrophic affects on engine components. Pistons, valves and cylinder heads must be cooled to reduce the risk of detonation. Cylinder temperatures need to be controlled so lubricating oil can maintain a protective film on the cylinder surfaces and the lubricating oil should be cooled to ensure its integrity. In addition to overheating, overcooling can have negative effects on the engine. Overcooling can reduce engine performance and shorten the engine’s service life. Cooling systems are used to manage engine heat. Cooling systems must be properly designed, operated and maintained for proper engine operation and service life [5].

An automobile radiator is a component of an automotive cooling system which plays a major role in transferring the heat from the engine parts to the environment through its complex system and working. It is a type of cross flow heat exchanger which is designed to transfer the heat from the hot coolant coming from the engine to the air blown through it by the fan. A small segment of the radiator is analyzed for the various speed of the air striking the radiator as the vehicle moves from its rest position to a certain speed. The heat transfer processes takes place from the coolant to the tubes then from the tubes to the air through the fins. After the analysis is carried out, the heat transfer coefficient of air and ethylene glycol is estimated and further overall heat transfer coefficient is calculated.

A compact heat exchanger analysis of the types used frequently in the automotive and aeronautical industries is performed. The compact finned-tube heat exchanger with flat fins was analyzed in greater depth since it is widely used in automotive radiators, the present study's primary object. The theory was developed to determine the heat transfer rate and pressure drop for this specific compact heat exchanger by applying the effectiveness (ε-NUT). The analyzed radiator is popularly known as a water cooler and is used in medium trucks with load capacities between 15 and 20 tons. The truck type has no turbo compressor, which implies the absence of an air cooler, or "intercooler. " The air that enters the fins makes it at room temperature. Theoretical versus experimental comparisons were made. Results allow us to conclude that the simulations performed are consistent when the input hypotheses defined as valid for the experiments are assumed. Stopping criteria for iterative processes, determining heat transfer rate and pressure drop, using the experimental data of a single available experiment, and need to be refined, for better characterization and robustness of theoretical procedure. There is a lack of empirical expressions in open literature. Large corporations, builders of compact heat exchangers, do not provide information obtained in their laboratories, since the data are strategic for the survival.

Politeknik Dergisi, 2019

A radiator test system was developed to test the heat transfer performance of automobile radiators for various engine coolants. The system was made up from a circulation pump, coolant reservoir, axial fan, electric heaters, PLC controlled drivers and instruments for various mechanical measurements along with the tested radiators. Two different radiators, namely round and flat tube ones, and four different engine coolants, namely water, ethylene glycol, their 50/50 mixture and a commercial heat transfer oil, were tested. The experimental heat dissipation rates of the radiators were evaluated under a broad range of operating conditions. The air speed was changed between 2 and 4 m s-1, the coolant flow rate was varied between 0.1 and 0.3 l s-1, and the air temperature at the inlets of the radiators was changed between 25 and 35 °C, while the coolant temperature was fixed at 90 °C in all tests. The flat tube radiator dissipated on average 4.8% more heat than the circular tube one for wa...

Abstract— An Automotive engine cooling system takes out of excess heat produced during engine operation. An automobile cooling system regulates engine surface temperature for engine optimum efficiency. Recent advancement and development in engine for power forced engine cooling system to develop new strategies to improve its performance efficiency. Also to reduce fuel consumption along with controlling engine emission to mitigate environmental pollution norms. This paper throws light on parameters which influence radiator performance along with reviews some of the conventional and modern approaches to enhance radiator performance. This review paper Focus on the various research papers regarding experimental, CFD and Numerical analysis to improving automobile radiator efficiency.

INPRESSCO, 2016

This paper gives study of design of a wet leak test machine, used for the detection of leakages in radiators. It is based on the technique of submerging the part in the water that is stored in an immersion tank. Immersion tanks are a widely used method for location of leakages in complex assemblies and products. The part under test is pressurized with air while being submerged in a liquid, typically water. The operator looks for a stream of bubbles indicative of a leak. Proper selection and implementation of a production leak test method starts with an understanding of why the test is being performed, followed by establishing what the leak rate limit is, and finally a determination of how the leak test will be performed.

A complete set of numerical parametric studies on automotive radiator has been presented in detail in this study. The modeling of radiator has been described by two methods, one is finite difference method and the other is thermal resistance concept. In the performance evaluation, a radiator is installed into a test-setup and the various parameters including mass flow rate of coolant, inlet coolant temperature; etc. are varied. A comparative analysis between different coolants is also shown. One coolant as water and other as mixture of water in propylene glycol in a ratio of 40:60 is used. It is observed that that the water is still the best coolant but its limitation is that it is corrosive and contains dissolved salts that degrade the coolant flow passage.

EPJ Web of Conferences, 2013

Paper deal about testing of device with heat pipes and about research alternative possible applications of heat pipes and potential improvements in purpose effective heat sink from power switches of device. This device is used in various static and moveable applications. Testing device is part of control unit in rail vehicle. The amount of heat produced by power switches depend from working conditions of static converter. Great impact on heat sink has, how as season also this if the vehicle is moving or don't moving. If the vehicle is moving the heat transfer form energy converter to surrounding is caused by forced convection of air flow around device. But the critical conditions occur if the vehicle doesn't move, because the application of this cooling device is based on natural convection. The study deal solution of the problem heat transfer from energy converter to surrounding by natural convection. This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2 0 , which. permits unrestricted use, distributi and reproduction in any medium, provided the original work is properly cited.

Highlights:  Designing of a wavy and louvered fin based heavy vehicle automotive radiator.  CFX simulation of cross flow heat transfer of nanofluids in circular tubes.  To evaluate the fluid flow analysis and cooling capacity by estimating temperature distribution of nanofluid as coolant. Abstract: In continuous technological development, an automotive industry has increased the demand for high efficiency engines. A high efficiency engines is not only based on its performance but also for better fuel economy and less emission rate. Researches in heat transfer have been carried out over the previous several decades, leading to the development of the currently used heat transfer enhancement techniques. Radiator is one of the important parts of the internal combustion engine cooling system. So improving the performance and reducing cost of radiator is the necessary research. For higher cooling capacity of radiator, addition of fins is one of the approaches to increase the cooling rate of the radiator. The water and ethylene glycol as conventional coolant have been widely used in an automotive radiator in many years. With the advancement of nanotechnology, a coolant are invented which is known as " nanofluids ". The Researchers found that these fluids offer higher thermal conductivity compared to that of conventional coolants. With these specific characteristics, the size and weight of an automotive car radiator can be reduced without affecting its heat transfer performance. An automotive radiator (Wavy and Louvered fin type) model is modeled on modeling software CATIA V5 and performance evaluation is done on pre-processing software ANSYS 14.0. Present study outline that the use of fins and nano fluid may improve the performance of automotive radiator. Results have shown that the rate of heat transfer is better when nano fluid (Si C + water) is used as coolant, than the conventional coolant.