Introduction: Methane is one of the most widely used gases in industries with a high flammability potential. This study aimed to evaluate the efficiency of ventilation systems installed on methane valve pits based on hazardous areas classification. Material and Methods: This study was implemented in a steel industry in Qom Province in 2019. The tools used in this study were a DELTA OHM pitot t...

Introduction: Rheumatic heart disease still remains one of the leading causes of congestive heart failure and death owing to valvular pathologies, in developing countries. Valve replacement still remains the treatment of choice in such patients.The aim of this study wasto analyze the postoperative outcome of  double valve replacement (Mitral and Aortic ) in patients of rheumatic heart disease. ...

Since knowledge on hydrodynamic torque of a butterfly valve is very important for butterfly valve design, its hydrodynamic torque is investigated in this paper. In reality, the investigation of the loss coefficient and torque from some experiments will take a long time and a lot of money. This paper presents a statistical study of the flow past the butterfly valve in a static analysis using com...

Introduction: Prosthetic valve thrombosis is a rare and severe complication of valve replacement, most often encountered with a mechanical prosthesis. The significant morbidity and mortality associated with this condition warrant rapid diagnostic evaluation. Although surgery is the first-line therapy in symptomatic obstructive mechanical valve thrombosis, thrombolytic therapy has been used as a...

A computational optimization was performed for a direct-injection diesel engine using three-dimensional modeling. Fully transient CFD analyses of different valve profile strategies for the intake and compression strokes were performed to evaluate the effects on both engine performance and in-cylinder flow-field evolution. The turbulence model was used along with the second order linear upwin...

Small diesel engines are widely used for commercial vehicle and passenger car applications due to their higher torque requirements, fuel economy, and better thermal efficiency. These engines are exposed to different operating and environmental conditions and hence emissions from these engines are erratic. Strategies are required to enhance performance and reduce engine-out emissions considering...

introduction: aortic valve sclerosisis considered as a manifestation of coronary atherosclerosis. recent studies demonstrated an association between aortic valve sclerosis and obstructive coronary artery disease. the purpose of this study was to evaluatethe correlation betweenaortic valve sclerosis andobstructive coronary artery disease and the extent of coronary artery disease in patients hosp...

a 46 year old man had been undergone aortic valve replacement (avr) due to mechanical aortic valve endocarditis two month ago. he was referred to imam khomeini hospital because of dyspnea since two weeks ago. echocardiography showed the false aneurysm, with an area of flow beyond the lumen of the aorta. this patient underwent reoperation, the previously implanted aortic valve was removed, metic...

introduction fungal prosthetic valve endocarditis (pve) is rare but serious complication of valve replacement surgery. candida species, particularly candida albicans is the most common isolated pathogen in fungal pve (1–6%of cases). case presentation we describe a 35-year-old woman who underwent mechanical mitral valve replacement about 3 years ago. she was admitted with neurological symptoms a...