Master thesis for Annular Space Condensation in Refrigerated Ammonia Tanks (m/f)

Job description

At thyssenkrupp we have more than 156,000 employees in nearly 80 countries and annual sales of €39 billion. We are active in automotive engineering, logistics, plant technology, steel production, elevator manufacturing and much more. We work in large and small businesses all around the world – but we always work together. We have over 200 years of experience in industry and the latest cutting-edge technology. We have a position that‘s right for you, that piques your interest, and that puts your skills to the test.

Master thesis for Annular Space Condensation in Refrigerated Ammonia Tanks (m/f)
thyssenkrupp Industrial Solutions AG,
Dortmund

The thyssenkrupp Industrial Solutions business area is a leading partner for the engineering, construction and service of all industrial plants and systems. In addition to chemical, coke, cement and other industrial plants and refineries, our portfolio also includes mining, ore processing and port handling equipment along with corresponding services. In the naval sector we are a leading global system supplier for submarines and surface vessels. As an important system partner to our customers in the automotive, aerospace and battery industries we optimize the value chain and improve performance. In collaboration with our customers we develop top-quality solutions and deliver efficiency, reliability and sustainability over the entire life cycle. Around 19,000 employees at over 70 locations form a global network with a technology portfolio that guarantees maximum productivity and cost-efficiency.

The Network of Excellence (NoE) is a global Network within the Business Area Industrial Solution. It is comprised of functions like Project Management, Engineering, Procurement and Construction for the worldwide processing of our customized projects. The bundling of our competencies enables us to be even more efficient in the rapidly changing market environment. We are focused on service orientation and customer satisfaction which have a top priority.

Your tasks

Problem statement: Large ammonia storage tanks are mostly realized as full containment tanks. Such tanks consist of an roofless inner tank, holding liquid ammonia, surrounded by a secondary, gas and liquid tight tank containment. The gap in between the inner and the outer tank is the annular space. The inner and the outer tank are interconnected on the gas side.

Low water content ammonia is stored slightly above atmospheric conditions, at a temperature of approx. -32.5°C. The tank pressure is maintained by an external refrigeration system.

In few instances, a significant level of high water content ammonia is found in the annular space after several months of operation. A condensation and evaporation process is suggested to explain the liquid phase formation and water enrichment.

The cold, outer wall of the inner tank acts as a condenser, while the warm, inner wall of the outer tank acts as an evaporator. Pressure fluctuations as well as liquid level changes within the tank might influence the condensation and evaporation rate.

Your tasks

Develop a 2D model describing the annular space condensation and evaporation rate as well as the water enrichment of the condensate as a function of:

·  Ambient heat input
·  insulation thickness
·  insulation location (on inner or outer tank wall)
·  ammonia water content in inner tank
·  filling height of inner tank
·  tank pressure
·  tank geometry (size)

Coding of the model in MATLAB or a programming language, such as .net, Java, VB, C++ or similar, involving:

·  heat and mass transfer equations
·  numerical solver module
·  physical properties module
·  input / output interface

Model verification: comparison of available field data versus model predicted data

Design Optimization: study, if shifting of the insulation (from outer wall to inner tank wall) or insulation thickness reduction avoids annular space condensation or rise of condensate level

The thesis shall be written in German or English.

Your profile

·  Student of chemical engineering or process engineering
·  Coding experience and a sound understanding of heat and mass transfer
·  Very good achievements during university studies
·  Fluent in German and English
·  High motivation and strong analytical skills

About thyssenkrupp
At thyssenkrupp we have more than 156,000 employees in nearly 80 countries and annual sales of €39 billion. We are active in automotive engineering, logistics, plant technology, steel production, elevator manufacturing and much more. We work in large and small businesses all around the world – but we always work together. We have over 200 years of experience in industry and the latest cutting-edge technology. We have a position that‘s right for you, that piques your interest, and that puts your skills to the test.

About thyssenkrupp Industrial Solutions AG

The thyssenkrupp Industrial Solutions business area is a leading partner for the engineering, construction and service of all industrial plants and systems. In addition to chemical, coke, cement and other industrial plants and refineries, our portfolio also includes mining, ore processing and port handling equipment along with corresponding services. In the naval sector we are a leading global system supplier for submarines and surface vessels. As an important system partner to our customers in the automotive, aerospace and battery industries we optimize the value chain and improve performance. In collaboration with our customers we develop top-quality solutions and deliver efficiency, reliability and sustainability over the entire life cycle. Around 19,000 employees at over 70 locations form a global network with a technology portfolio that guarantees maximum productivity and cost-efficiency.

The Network of Excellence (NoE) is a global Network within the Business Area Industrial Solution. It is comprised of functions like Project Management, Engineering, Procurement and Construction for the worldwide processing of our customized projects. The bundling of our competencies enables us to be even more efficient in the rapidly changing market environment. We are focused on service orientation and customer satisfaction which have a top priority.

Your tasks

Problem statement: Large ammonia storage tanks are mostly realized as full containment tanks. Such tanks consist of an roofless inner tank, holding liquid ammonia, surrounded by a secondary, gas and liquid tight tank containment. The gap in between the inner and the outer tank is the annular space. The inner and the outer tank are interconnected on the gas side.

Low water content ammonia is stored slightly above atmospheric conditions, at a temperature of approx. -32.5°C. The tank pressure is maintained by an external refrigeration system.

In few instances, a significant level of high water content ammonia is found in the annular space after several months of operation. A condensation and evaporation process is suggested to explain the liquid phase formation and water enrichment.

The cold, outer wall of the inner tank acts as a condenser, while the warm, inner wall of the outer tank acts as an evaporator. Pressure fluctuations as well as liquid level changes within the tank might influence the condensation and evaporation rate.

Your tasks

Develop a 2D model describing the annular space condensation and evaporation rate as well as the water enrichment of the condensate as a function of:

·  Ambient heat input
·  insulation thickness
·  insulation location (on inner or outer tank wall)
·  ammonia water content in inner tank
·  filling height of inner tank
·  tank pressure
·  tank geometry (size)

Coding of the model in MATLAB or a programming language, such as .net, Java, VB, C++ or similar, involving:

·  heat and mass transfer equations
·  numerical solver module
·  physical properties module
·  input / output interface

Model verification: comparison of available field data versus model predicted data

Design Optimization: study, if shifting of the insulation (from outer wall to inner tank wall) or insulation thickness reduction avoids annular space condensation or rise of condensate level

The thesis shall be written in German or English.

Your profile

·  Student of chemical engineering or process engineering
·  Coding experience and a sound understanding of heat and mass transfer
·  Very good achievements during university studies
·  Fluent in German and English
·  High motivation and strong analytical skills

Was wir Ihnen bieten

Together with a strong team and with our colleagues’ expertise, we are shaping digital change. Do you want to be part of what we do? Then join our team!

We work together closely and respect each other, for over 200 years now and up till today. If that is just as important to you as it is to us, apply now!

Was wir Ihnen bieten

Together with a strong team and with our colleagues’ expertise, we are shaping digital change. Do you want to be part of what we do? Then join our team!

We work together closely and respect each other, for over 200 years now and up till today. If that is just as important to you as it is to us, apply now!