The effect of ceramic coating on the performance and emissions of a diesel engine

Dissertant

Hamid, Ahmad Sabah

Thesis advisor

Mashkour, Mahmud A.
Mahmud, Ibtihal Abd al-Razzaq

University

University of Technology

Faculty

-

Department

Mechanical Engineering Department

University Country

Iraq

Degree

Master

Degree Date

2011

English Abstract

The effect of ceramic coating on the performance and emissions of a dieseJ engine was investigated.

The research engine was a four-stroke, direct injection, single cylinder, diesel engine.

This engine was tested at constant speed and different load conditions without coming.

Then, the inlet Eind exhaust valves faces were coated with about 500jim ceramic materials.

Ceramic layers were made of 350-400 j.im of SS'iYttria-Stabilized Zirconia (S%YSZ), and 50-100 (iim of 4NiC'r5AI as a Kind 0(ia(,The coaling tcchniquc used is the flame spray method.

The ceramic-coated research engine was tested at the same operation conditions as the conventional (without coating) engine.

The measurements showed a reduction in fuel consumption of about 7.6% and exhaust emissions w ere about (13% for HC and 14.5% for CO and 14% for CO:) .However, the exhaust gas temperature was increased by 34.5 “C {on average} after coating.

Then, piston was coated also with the same ceramic materials (8%YSZ) and 4NiCr5Al as the bond coat and with the same thickness of about 500 The engine was tested at standard conditions to set the effect of coated surfaces of valves and piston on the performance and emissions of the engine.

The ceramic-coated engine was compared to the conventional uncoatcd engine.

I he results of valves and pislon test together indicate a reduction in fuel consumption by about I 7.2% and exhaust emissions about (29.7% for HC and 30,7% for CO and 34.7% for CO:).

Hxhaust gas temperature under this condition was increased by about 72 °C (on average).

Wear test measurements also showed that (8%YSZ) gives better wear resistance in comparison with the bare piston alloy under wear test.

The total weight loss reduction ai a load of 0.5 kg was 9.2 *10-a % for YSZ, while it was 0.017% lor ban; piston alloy and 0.013% lor YSZ at load 1.02 kg .while it was 0.04 % fur bare piston alloy.

At a load of 1,5 kg, the total weight toss reduction was 0.023% for VSZ, hut it was 0.077% for the bare piston alloy under Ihe same load.

I he X- ray analysis of resultant coatings showed the presence of a number of crystalline phases Jbrmed during heal treatments like monoclinic and tetragonal.

To assess the adhesion strength and the hardness of the coating, the adhesion strength between the substrate, and the coating iavers was measured and found equals to (25) MPa and the hardness value is (650) MPa.

Main Subjects

Mechanical Engineering

Topics

• Islamic jurisprudence
• Automobiles
• Asphyxiating gases

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-427695