Optimization principle of operating parameters of heat exchanger by using CFD simulation

Abstract

Abstract. Design of effective heat transfer devices and minimizing costs are desired sections in industry and they are important for both engineers and users due to the wide-scale use of heat exchangers. Traditional approach to design is based on iterative process in which is gradually changed design parameters, until a satisfactory solution is achieved. The design process of the heat exchanger is very dependent on the experience of the engineer, thereby the use of computational software is a major advantage in view of time. Determination of operating parameters of the heat exchanger and the subsequent estimation of operating costs have a major impact on the expected profitability of the device. There are on the one hand the material and production costs, which are immediately reflected in the cost of device. But on the other hand, there are somewhat hidden costs in view of economic operation of the heat exchanger. The economic balance of operation significantly affects the technical solution and accompanies the design of the heat exchanger since its inception. Therefore, there is important not underestimate the choice of operating parameters. The article describes an optimization procedure for choice of cost-effective operational parameters for a simple double pipe heat exchanger by using CFD software and the subsequent proposal to modify its design for more economical operation.

Determination of the Working Parameters of the Biomass Boiler

“…This is less than 1 % of the solar radiation that will reach this area per year. Further losses are incurred when biomass is processed into fuel and burned to obtain heat or electricity [1,2].…”

“…Biomass in terms of possible energy use includes any organic source containing bound chemical energy, wood and wood waste in various forms, agricultural crops and waste, animal and food waste and biodegradable fractions of industrial and municipal waste [1,3]. Unlike fossil fuels -coal, oil and natural gas -the combustion of fresh (non-fossil) biomass is almost neutral in terms of carbon dioxide (the main greenhouse gas) emissions in a changing climate.…”

“…Unlike fossil fuels -coal, oil and natural gas -the combustion of fresh (non-fossil) biomass is almost neutral in terms of carbon dioxide (the main greenhouse gas) emissions in a changing climate. Indeed, the amount of carbon in the form of carbon dioxide produced by the combustion of non-fossil biomass is equal to the amount of carbon that plants have "withdrawn" from the atmosphere through photosynthesis during their lifetime [1,4]. Energy can be extracted from biomass in several ways, which can be divided into three basic categories:  Thermochemical conversion (direct combustion, pyrolysis or gasification).…”