(Cooling is one of the prime important technical challenges facing by numerous industries such as automobiles, electronics, chemical, food and manufacturing etc..Traditional heat transfer fluids such as water, oil, and ethylene glycol mixtures are inherently show poor heat transfer characteristics. With increasing global demand and competition, industries need to develop the advanced heat transfer fluids with significantly higher thermal conductivity than water. The thermal conductivity of heating or cooling fluids is a very important property for the development of energy efficient heat transfer equipments. Meanwhile, in all the processes involving heat transfer, the thermal conductivity of the fluid is one of the basic important property …show more content…
The convective heat transfer can be improved passively by changing the flow geometry, boundary conditions, or by enhancing the thermal conductivity of the fluid. Many researchers have tried to increase the heat transfer rate of fluids by increasing the thermal conductivity .Thermal conductivity of nanofluids is found to be an important characteristic for many applications in present world. Conductivity is the ability of a material to conduct or transmit heat. Considerable amount of research have been carried out on measuring thermal conductivity of nanofluids. It has been found by many researchers that the nanofluids provide higher thermal conductivity compared to base fluids. Its value increases with the increase in particle concentration, temperature, particle size, dispersion and stability. Nevertheless, it is expected that other factors like Density, Viscosity, Specific Heat are also responsible for the convective heat transfer enhancement of …show more content…
The important engineering applications of heat exchangers are in power plants, air-conditioning, petrochemical industry, natural gas processing, refrigeration, solar water heater, chemical reactors, sewage treatment, shell and tube heat exchangers in nuclear reactors and in food industry. The design method for heat exchangers is very critical, as it needs perfect analysis on rate of heat transfer and pressure drop estimations. The major challenge in modeling of heat exchangers are to make the equipment compact and attain a high heat transfer rates by using less pumping power. The high material and energy costs, causes an increased effort to target at producing most durable equipments. Further, sometimes there is a necessity for miniaturization in particular aspects, such as aviation application, electronic gadgets etc., by increasing the heat transfer rates. The rate of heat transfer can be enriched by producing a disturbance in the flow of fluid by breaking the viscous boundary and thermal boundary layers, but in this process, pumping power may increase steeply and the pumping cost becomes very high. So to achieve a sought heat transfer rate in heat exchanger, numerous techniques have been suggested in recent years, such as twisted tape inserts, coil wire inserts, longitudinal inserts, and
Nano-thermal analysis methods are also known as micro-thermal procedures and they use the principle of characterizing highly localized materials on a micrometer. The characterization is then changed from a micrometer scale to a sub-micrometer scale with the temperature being regulated to the specified units. The application of nano-thermal analysis methods started towards the end of the 20th century. Although it has been applied in several other fields including microelectronics, its application in pharmaceuticals has not been that popular.
An Investigation Into How the Thickness of Insulation Affects the Time a Drink Takes to Cool Down
The data which was collected in Procedure A was able to produce a relatively straight line. Even though this did have few straying points, there was a positive correlation. This lab was able to support Newton’s Law of Heating and Cooling.
There are three different types of ways heat can be transferred, and that is conduction, convection, and radiation. Radiation is a heat transfer that involves heat absorption such as the sun producing heat and the Earth absorbing the heat. Second is conduction, which is the process of heat being transferred through metal. an example of this would be heating up one end of a metal pipe and the other end of the pipe will begin to get hotter. Lastly is convection, which is heat transf...
As a result of the design parameters from the experimental column, the following design is proposed: the column will run at a vapor velocity of 4.85 ft/hr and will have a HETP of 4.30 inches. This will result in a packing height of 38.7 feet. The reboiler will have an area of 113.52 ft2 and the area of the condenser will have a value of 45.54 ft2 in which heat exchange will take place.
In order to study the aspects of fluid mechanics that need to be taken into account when constructing our cooling tower, a breakdown of different behaviours of fluids under different conditions must be performed and tested against the flow rate. The experimental design would have to explore the influence of the length of the flow pipe as well as the density and temperature on the flow rate of the fluid.
Specific heat capacity of aqueous solution (taken as water = 4.18 J.g-1.K-1). T = Temperature change (oK). We can thus determine the enthalpy changes of reaction 1 and reaction 2 using the mean (14) of the data obtained. Reaction 1: H = 50 x 4.18 x -2.12.
Nano-Brewery is a small community micro-brewery in which has experienced a good level of success with their current craft beer products as they are now looking to expand their product mix. After completing the necessary steps to obtain their liquor license, Nano-Brewery is unsure of its financial strength as it will need to be assessed to determine their capacity for expansion and growth. The small brewery operates as a corporation structured by two equal stockholders. Sales and administration is managed by one partner while the other’s focus is on brewery operations. Two employees were recently hired, one as a brewery assistant and the other with emphasis on external sales.
The next type of heat transfer is convection. Convection is heat transferred by a gas or liquid. Such as dumping hot water into a cold glass of water, making the water overall warmer. The last type of heat transfer is radiation.
...he principle numbers of Froude, Reynolds and Weber. Mathematical model predicts the heat and mass transfer in numerical framework for both transports phenomena of relevance to the industry continuous casting tundish system. Additionally, it has an excellent agreement outlet temperature respond the step input temperatures in the inlet stream of water in the tundish model. The simulations of 8x8 grid and 16x16 grid are applied to obtain significant difference between the TAV maps in which both grids are computed by software represent the specific flow of the fluid in the model and the steel caster as the actual size system. Therefore, the physical and mathematical modeling is used as a guidance to build a model before the prototype is constructed in terms of calculation, measurement and determination of specific fluid flow, heat and mass transfer in the water model.
The process of conduction between a solid surface and a moving liquid or gas is called convection. The motion of the fluid may be natural or forced. If a liquid or gas is heated, its mass per unit volume generally decreases. If the liquid or gas is in a gravitational field, the hotter, lighter fluid rises while the colder, heavier fluid sinks. For example, when water in a pan is heated from below on my stove, the liquid closest to the bottom expands and its density decreases. The hot water as a result rises to the top and some of the cooler fluid descends toward the bottom, thus setting up a circulatory motion. This is also why the heating of a room by a radiator depends less on radiation than on natural convection currents, the hot air rising upward along the wall and cooler air coming back to the radiator from the side of the bottom. Because of the tendencies of hot air to rise and of cool air to sink, radiators are positioned near the floor and air-conditioning outlets near the ceiling for maximum efficiency.
Capillary action can only occur when the adhesive forces are stronger than the cohesive forces, which creates surface tension in liquid. The kinetic energy produced when the liquid is heated, allows the attractive forces between the molecules to weaken and this causes them to move past each other more freely. This results in the liquid flowing more easily. Therefore temperature increases capillary action and capillary flow because of the decrease in cohesive force. The intermolecular forces between the molecules are less packed due to the increase in temperature and the surface tension in the liquid will decrease as the temperature increases and this will help the flow of the liquid through the capillary tube.
Life changed immensely in the 20th century as air conditioning and refrigeration systems became more efficient and controllable. Air Conditioning and Refrigeration play important roles in providing human comfort, food processing, storage, and many other industrial processes. We chose this topic because our life would be difficult without AC and Refrigeration. This paper will talk about the history of air conditioning and refrigeration, the role of engineers in designing and building it, people’s life before and after air conditioning and refrigeration, and finally Applications in the area of achievements and future developments.
I have chosen nanotechnology as my topic area of choice from the food innovation module.
The objective of this study is to evaluate the effects of wire length and temperature of wire on electrical conductivity and resistivity.