In a shell and tube heat exchanger, the failure of tube-to-tubesheet welds results in high-pressure water jet which erodes the refractory in front of the tubesheet. Finite element method was employed to simulate the welding process and post weld heat treatment (PWHT) to find the factors affecting the failure in tube-to-tubesheet weldments. Residual stresses in two different geometries of tube-t...

This study explores the endothermic dehydriding (desorption) reaction that takes place in a high-pressure metal hydride (HPMH) hydrogen storage system when hydrogen gas is released to the fuel cell. The reaction is sustained by circulating warm fluid through a heat exchanger embedded in the HPMH powder. A systematic approach to modeling the dehydriding process is presented, which is validated a...

The need for energy efficient, low cost, and reduced material solutions are encouraging HVAC&R engineers to explore new heat exchanger designs, including those using small diameter tubes and tubes with internal enhancements. Such developments thus require review and consideration for new and/or improved heat exchanger manufacturing techniques. Experimental and analytical study of a pressure exp...

Heat transfer coefficients were measured in a circular tube with dimpled surface. The almond type dimples were fabricated, the tube diameter (D) 19mm and dimple depth 3 mm ratio was kept constant, while holding diameter 10mm of dimple is required length 21.5mm because of the elongated shape. The Reynolds number based on the channel hydraulic diameter was varied from 25000to 95000. An experiment...

Cross flow water tube heat exchanger can be designed and made operational using methods of model building and simulation of the system. This paper projects the design and development of a model of cross flow water tube heat-exchanger system, simulation and validation of control analysis of different tuning methods. Feedback and override control system is developed using inputs acquired with the...

An experimental study on the effects of various factors(fin spacing, fin arrangement, air temperature, air humidity, and air velocity) on the frost growth and thermal performance of a finned-tube heat exchanger has been conducted under the frosting condition. It is found that the thermal performance of a heat exchanger is closely related to the blockage ratio of air flow passage due to the fros...

In this study, the effect of the tube material on the thermal stress generated in a vertical shell and tube heat exchanger is investigated. Shell and tube heat exchangers are the most common heat exchangers used in industries. One of the most common failures in these exchangers in the industry is the tube failure at the junction of the tube to tubesheet. When the shell side and the tube side fl...

Over 85% of all new heat exchanger applications in oil refining, chemical, petro-chemical, and power generation are accommodated through the use of conventional shell and tube type heat exchangers. The fundamental basis for this statistic is shell and tube technology is a cost effective, proven solution for a wide variety of heat transfer requirements. However, there are limitations associated ...