Symmetry in mathematical optimisation is of broad and current interest. In problem classes such as mixed-integer linear programming (MILP), equivalent solutions created by symmetric variables and constraints may combinatorially increase the search space. Identifying problem symmetries is an important step towards expediting tree-based algorithms such as branch-and-cut because computationally cl...

The deterioration of the performance of a cross flow heat exchanger with condensation due to the longitudinal conduction was investigated. For a relatively small change of wall temperature along the flow directions which was shown to be common in many applications, the energy equations were solved numerically. An iterative method was used to solve the resulting equations of the finite differenc...

Joule-Thomson cooling systems are used in refrigeration and liquefaction processes. There are extensive studies on Joule-Thomson cryogenic systems, but most of them coverage steady state conditions or lack from experimental data. In the present work, transient thermal behavior of Joule-Thomson cooling system including counter current helically coiled tube in tube heat exchanger, expansion valve...

The energy recovery performance of crude pre-heat trains (PHTs) in oil refineries is typically impaired by deposition over time of fouling on the thermal surfaces. Such time varying effects are normally not considered in the design or retrofit of heat exchangers networks. In this paper, the importance of taking into account such effects is demonstrated, bymeans of a case study. An existing indu...

This paper proposes a new MINLP model for heat exchanger network synthesis that includes streams with phase change. The model considers every possible combination of process streams that may arise within a chemical process: streams with sensible heat, streams with latent heat, and streams with both latent and sensible heat. As part of the optimization strategy, the superstructure is modeled wit...

Compact heat exchangers (CHE) are very well known for their special design which includes high heat transfer coefficient and maximum temperature driving force between the hot and cold fluids. The accurate prediction of the thermal performance of a compact heat exchanger in the design stage is highly desirable for most aerospace applications. In the present study, the numerical investigation for...

Waste heat recovery is very important, because not only it reduces the expenditure of heat generation, but also it is of high priority in environmental consideration, such as reduction in greenhouse gases. One of the devices is used in waste heat recovery is heat pipe heat exchanger.Anexperimental research has been carried out to investigate the hydrodynamic and thermal performance of a gas...

Process integration methods aim at identifying options for heat recovery and optimal energy conversion in industrial processes. By applying pinch analysis methods, the first step is to calculate the maximum heat recovery between cold and hot streams. The second step consists in designing the corresponding heat recovery exchanger network, based on a fixed list of streams. For the heat cascade, i...